2018-05-24T05:36:00Z http://www.academicjournals.org/oai-pmh/handler
oai:academicjournals.org:AJB:3D7E3A3635 2002-11-30T00:00:00Z AcademicJournals AJB AJB:2002
Episodic bioavailability of environmental mercury: implications for biotechnological control of mercury pollution O. A. Ogunseitan Perennial wildfires in Africa and other continents contribute an estimated 8 x 105 kg of mercury to the global atmosphere with a residence time of approximately one year. This phenomenon changes the flux of biologically available mercury in natural microbial communities where enzymatic actions, including mercuric reductase and organomercurial lyase activities, underpin the biogeochemical cycling of mercury with repercussions for human exposure to toxic forms of the element. To elucidate the impact of episodic mercury bioavailability on the response of microbial communities, the expression of microbial proteins and nucleic acids in environmental strains of Pseudomonas species were evaluated under various concentrations of mercury ranging from 0 to 500 M. Routine cultivation of Pseudomonas aeruginosa PU21 containing the 142.5 kb plasmid Rip64 in medium containing 100 g of Hg++/ml (500 M) exhibited a prolonged lag phase survived by hyper-resistant cells able to grow in medium containing 200 g of Hg++/ml. Nucleic acid analyses showed a distinct mutation in the merA gene encoding for mercuric reductase activity in cells able to grow at elevated mercury concentrations. A similar mutation was detected in the merR locus which serves as the regulator of themer operon. Mutations were not detected in merC which encodes for a hydrophobic membrane-associated protein implicated in active mercury transport. Protein profiles of cells grown with elevated mercury concentrations were associated with a stable increase in the production of specific polypeptides. In addition, the survival and genetic response of naturally-occurring mercury resistant bacteria inoculated into contaminated environmental samples were monitored in microcosm experiments over a 30 day period. The results suggest that sudden exposure to high concentrations of mercury either decimates the bacterial population or selects for hyper-resistant strains with high level of constitutive expression of active proteins, including mercuric reductase. Methyl mercury was observed to cause a higher level of induction for mercuric reductase than the specific substrate, inorganic mercury. The selection of hyper-resistant strains is potentially useful for biotechnological strategies to control the bioavailability of mercury, and thereby potentially reducing the re-uptake of mercury into vegetation in regions frequently subjected to wildfires. Key words: Mercury pollution, wildfires, mercuric reductase, organomercurial lyase, proteomics, microorganisms, detoxification. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3D7E3A3635 http://dx.doi.org/10.5897/AJB2002.000-001 en Copyright © 2002 O. A. Ogunseitan
oai:academicjournals.org:AJB:3097501638 2002-11-30T00:00:00Z AcademicJournals AJB AJB:2002
Swarming modulatory effects of some amino acids on Proteus strains from Lagos, Nigeria Bamidele A. Iwalokun and Babatunde O. Akinwumi Swarming motility, a multicellular behaviour characterized by periodic concentric growth on solid media has severally been reported as a constraint in the clinical investigation of mixed-culture infections involving Proteus and as a requirement for virulence. While media are being formulated to restrain swarming in this organism, the roles played by amino acids in the biogenesis of swarming have not been fully clarified. The effects of 20 amino acids on swarming, extracellular protease activity, cellular RNA level and total protein concentration in 20 clinical Proteus strains from Lagos, Nigeria were investigated. At 0.5mM concentration, glutamine, serine, and methionine were the only amino acids found to enhance swarming motility on M9 minimal medium (7.1ndash;11.3 mm), cause significant increases in protease activity (33.7ndash;48.3 units/ml), total protein concentration (22.5ndash;28.6 mg/ml) and cellular RNA concentration (192.8ndash;264.7 mg/ml) when compared to values obtained for other 17 amino acids (P lt; 0.05). Furthermore, the amino acid induced swarming in these strains was found to vary directly and significantly (P lt; 0.05) with protease activity and cellular RNA concentration. The exclusion of methionine, serine and glutamine when supplementing antiswarming media for clinical investigation of Proteus - associated polymicrobial infections in Nigeria is suggested. Key words: Proteus strains, swarming motility, amino acids, Lagos. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3097501638 http://dx.doi.org/10.5897/AJB2002.000-002 en Copyright © 2002 Bamidele A. Iwalokun and Babatunde O. Akinwumi
oai:academicjournals.org:AJB:0409D24655 2002-11-30T00:00:00Z AcademicJournals AJB AJB:2002
Biological nitrogen fixation in Crotalaria species estimated using the 15N isotope dilution method R.T. Samba, S.N. Sylla, M. Neyra, M. Gueye, B. Dreyfus and I. Ndoye A greenhouse experiment was conducted to measure nitrogen fixation in threeCrotalaria species : C. ochroleuca, C. perrottetii and C. retusa growing in Senegal by using 15N direct isotope dilution technique. Two non-fixing plants, Senna obtusifoliaand Senna occidentalis served as reference plants. The amount of nitrogen fixed two months after planting was obtained using the average of the two reference plants. The atom % 15N excess in the Crotalaria species was significantly lower than that of the reference plants, indicating that significant nitrogen fixation occurred in the three plants. Significant differences were observed between the Crotalaria species; C. ochroleucayielded more dry matter weight and total nitrogen than did C. perrottetti and C. retusa. The % nitrogen derived from atmosphere (%Ndfa) in leaves and stems was also higher in C. ochroleuca. There was no significant difference in %Ndfa in the whole plant between the three Crotalaria species (47% to 53%). In contrast, interspecific variability was observed based on the %Ndfa. C. ochroleuca significantly exhibited the higher amount of total nitrogen fixed, equivalent to 83 kg of nitrogen fixed per hectare. Based on these data, it was concluded that C. ochroleuca could be used in multiple cropping systems in Senegal for making more nitrogen available to other plants. Key words: Crotalaria spp, isotope dilution, 15N, nitrogen fixation, reference plant. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/0409D24655 http://dx.doi.org/10.5897/AJB2002.000-003 en Copyright © 2002 R.T. Samba, S.N. Sylla, M. Neyra, M. Gueye, B. Dreyfus and I. Ndoye
oai:academicjournals.org:AJB:B206BBB657 2002-11-30T00:00:00Z AcademicJournals AJB AJB:2002
Persistence of Rhizobium inoculants originating from Leucaena leucocephala fallowed plots in Southwest Nigeria O.A. Ojo and O.E. Fagade Ten core soil samples were collected from experimental plots at IITA, SW Nigeria that were previously inoculated with Rhizobium strains (IRC1045 and IRC 1050) specific for Leucaena leucocephala at two depths; 0ndash;15 cm and 15ndash;30 cm. The control soil samples were collected at similar depths from an adjacent field with no previous history of legume cultivation. Six weeks after planting of L. leucocephala in the soil samples in the greenhouse shoots, roots and nodules were harvested aseptically. Typing of the nodules as well as the identification of the persisting population of the introduced strains were based on the intrinsic resistance of IRC 1045 and IRC 1050 to streptomycin at 500 mg/ml and nodules were found to be made up of 100% of previously introduced strains. The potency and competitive ability of the recovered IRC 1045 and IRC 1050 were thus confirmed via the pot experiment and plant reinfection experiment in the greenhouse. At 0ndash;15 cm and 15ndash;30 cm depths 8.0 x 104 and 9.0 x 104 rhizobia/g of soil were recovered respectively in spite of the 10-year fallow period. Biomass production with the three woody legumes revealed Root and Shoot dry weights of the following order of magnitude Senna siamea gt; L. leucocephala gt; Senna spectabilis. This report showed the great potential of application of Rhizobium technology in low input sustainable agricultural practice and environmental pollution abatement for non-use of chemical nitrogen fertilizers. Key words: Agriculture, Leucaena leucocephala, nodulation, persistence, rhizobium. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/B206BBB657 http://dx.doi.org/10.5897/AJB2002.000-004 en Copyright © 2002 O.A. Ojo and O.E. Fagade
oai:academicjournals.org:AJB:3FCE5D66374 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Physiological and molecular insights into drought tolerance Sagadevan G Mundree, Bienyameen Baker, Shaheen Mowla, Shaun Peters, Saberi Marais, Clare Vander Willigen, Kershini Govender, Alice Maredza, Samson Muyanga, Jill M Farrant and Jennifer A Thomson Minireview Water is a major limiting factor in world agriculture. In general, most crop plants are highly sensitive to even a mild dehydration stress. There are however, a few genera of plants unique to Southern Africa, called ldquo;resurrection plantsrdquo; which can tolerate extreme water loss or desiccation. We have used Xerophyta viscosa, a representative of the monocotyledonous resurrection plants to isolate genes that are associated with osmotic stress tolerance. Several genes that are differentially expressed, and that confer functional sufficiency to osmotically-stressed Escherichia coli are being studied at the molecular and biochemical levels. In this review, we use this as a basis to discuss the physiological and molecular insights into drought tolerance. Key words: Drought stress, reactive oxygen species, osmoprotectants, abscisic acid, transcription factors. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3FCE5D66374 http://dx.doi.org/10.5897/AJB2002.000-006 en Copyright © 2002 Sagadevan G Mundree, Bienyameen Baker, Shaheen Mowla, Shaun Peters, Saberi Marais, Clare Vander Willigen, Kershini Govender, Alice Maredza, Samson Muyanga, Jill M Farrant and Jennifer A Thomson
oai:academicjournals.org:AJB:BEBDE066403 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
The diagnosis of trypanosome infections: applications of novel technology for reducing disease risk Picozzi, K., Tilley, A., Fegrave;vre, E.M., Coleman, P.G., Magona, J.W., Odiit, M., Eisler, M.C and Welburn S.C. Full Length Research Paper Reliable DNA based methodologies to determine prevalence of trypanosome species in domestic livestock have been available for over 10 years. Despite this, they are rarely used to generate baseline data for control operations for these diseases in the field. Rather, such operations tend to rely on data which can be generated using low technology methods such as direct observation of parasites by light microscopy. Here we show the pitfalls of relying on such low tech methodology which, although simple in its application, can provide inaccurate and inadequate data on which to base control methodologies. Our analysis of 61 cattle selected for trypanosome carrier status by either microscopy, low PCV or poor condition score, showed that 90% were infected with trypanosomes while 84% of the total were infected with T. brucei. Diagnosis by PCR on buffy coat preparations on Whatmanreg; FTAreg; matrices was the most sensitive methodology relative to the gold standard, whereas microscopy was the least sensitive. Keywords: sleeping sickness, human African trypanosomiasis, epidemiology, chemotherapy, PCR. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/BEBDE066403 http://dx.doi.org/10.5897/AJB2002.000-007 en Copyright © 2002 Picozzi, K., Tilley, A., Fegrave;vre, E.M., Coleman, P.G., Magona, J.W., Odiit, M., Eisler, M.C and Welburn S.C.
oai:academicjournals.org:AJB:9E440F46435 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Monoterpenes reduced adducts formation in rats exposed to aflatoxin B1 J. Abiodun Elegbede and Michael N. Gould Full Length Research Paper Perillyl alcohol and d-limonene are naturally occurring plant compounds that exhibited anti-carcinogenic activities in mammary tumor models. The effects of these monoterpenes at the initiation stage of aflatoxin B1-induced hepatocarcinogenesis were investigated. Male F344 rats were fed Control or treatment diets throughout the study and exposed to aflatoxin for 5 days. Three days after the last aflatoxin dose, blood and liver samples were obtained. Analysis of liver samples showed that both limonene and perillyl alcohol significantly inhibited (plt;0.05) aflatoxin-DNA adducts formation in hepatocytes. The monoterpenes may have potential for use as chemopreventive agent against aflatoxin-induced liver cancer. Keywords: Aflatoxin B1, hepatocarcinogenesis, monoterpenes, chemoprevention. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/9E440F46435 http://dx.doi.org/10.5897/AJB2002.000-008 en Copyright © 2002 J. Abiodun Elegbede and Michael N. Gould
oai:academicjournals.org:AJB:70C85EC6463 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Estimates of biological nitrogen fixation by Pterocarpus lucens in a semi arid natural forest park in Senegal using 15N natural abundance method Sylla S N, Ndoye I, Gueye M, Ba A T and Dreyfus B Full Length Research Paper Nitrogen (N2) fixation by Pterocarpus lucens in a natural semi arid ecosystem, in Ferlo, Senegal was estimated using 15N natural abundance (part;15N) procedure. Other non-fixing trees accompanying P. lucens in the same area were also investigated as control. Results showed an important variation of part;15N in leaves between the nitrogen-fixing tree (P. lucens) and reference plants, whereas no significant differences were recorded in amount of nitrogen (%). The relative part;15N values (permil;) were higher in non-fixing plants than in fixing plants considered. Calculations of %Ndfa gave rates ranging between 26% and 49%. The values of %Ndfa depend largely on soil and the reference plants. The contribution of nitrogen derived from fixation in leaves reached 28.9 kg.N/ha and 10.8 kg.N/ha in ferruginous and in sandy soil respectively. Key words: Pterocarpus lucens, 15N natural abundance, semi arid lowland, biological nitrogen fixation, natural ecosystem Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/70C85EC6463 http://dx.doi.org/10.5897/AJB2002.000-009 en Copyright © 2002 Sylla S N, Ndoye I, Gueye M, Ba A T and Dreyfus B
oai:academicjournals.org:AJB:BADF1146488 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Bio-deterioration of breadfruit (Artocarpus Communis) in storage and its effects on the nutrient composition Amusa, N.A, Kehinde, I. A. and Ashaye, O. A Full Length Research Paper The bio-deterioration of breadfruit in storage and its effects on the nutrient composition of the fruit was investigated at Ibadan, Southwestern Nigeria. Freshly dropped fruits were stored under laboratory conditions for a period of 9 days. Aspergillus niger, Rhizopus stolonifer, Botryodiplodia theobromae, Mycovellosiella fulva, Penicillium sp. and Aspergillus flavus, were found associated with deteriorating breadfruit in storage The freshly harvested breadfruit has 70.2% carbohydrate which reduced to 59.4% within 9 days of storage under room temperature. The amount of fat content, protein and the energy of the breadfruit also reduced in fruit samples stored for 9 days, while there was an increase in the moisture content, crude fibre, and ash content of the breadfruits in storage. The mineral contents also increased during the period of storage. Key words: Artocarpous communis, bio-deterioration, breadfruit, storage nutrient composition, pathogens. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/BADF1146488 http://dx.doi.org/10.5897/AJB2002.000-010 en Copyright © 2002 Amusa, N.A, Kehinde, I. A. and Ashaye, O. A
oai:academicjournals.org:AJB:196E8806508 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Effect of cold temperature storage on the quality attributes of pawpaw and guava leathers Babalola S. O., Ashaye O. A., Babalola A. O. and Aina J.O. Short Communication The effect of cold temperature storage on the quality attributes of pawpaw and guava leathers was evaluated. Pawpaw leather was significantly higher than guava leather in calorific content, water activity, pH and total mould count throughout the duration of storage. However Guava leather was higher in texture. Sensory scores in relation to period of storage showed that Guava leather gave better result in overall acceptability at zero, one and two months of storage at 8 plusmn; 10C. Guava leather also gave better sensory qualities in fruitiness, smell, chewiness, toughness, colour, and overall acceptability when varietal influence is considered. Guava leather is better accepted. Key words: Pawpaw, guava sensory, leather, storage. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/196E8806508 http://dx.doi.org/10.5897/AJB2002.000-011 en Copyright © 2002 Babalola S. O., Ashaye O. A., Babalola A. O. and Aina J.O.
oai:academicjournals.org:AJB:4EE56EA6542 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Influence of carbon source on the expression of Cochliobolus carbonum xylan-degrading enzyme genes Nyerhovwo J. TonukariY, , John S. Scott-Craig and Jonathan D. Walton Short Communication The expression of four Cochliobolus carbonum endo-1,4-b-xylanase genes (XYL1,XYL2, XYL3, XYL4), and an exo-1,4-b-xylosidase gene (XYP1) was studied following the growth of the fungus in minimal medium containing glucose, sucrose, xylose, xylan, pectin, or cellulose. The XYL1 and XYL2 genes were expressed only when the culture medium contained xylan or cellulose. Both XYL3 and XYL4 are induced by xylose and xylan, and XYP1 expression is induced by xylose, xylan, pectin and cellulose. None of these genes is expressed in glucose or sucrose media. The differential expression of these enzymes may provide means for the fungus to adapt to different conditions. Key words: Cell wall degrading enzymes, Cochliobolus carbonum, xylan, xylanase. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/4EE56EA6542 http://dx.doi.org/10.5897/AJB2002.000-012 en Copyright © 2002 Nyerhovwo J. TonukariY, , John S. Scott-Craig and Jonathan D. Walton
oai:academicjournals.org:AJB:193B7056569 2002-12-30T00:00:00Z AcademicJournals AJB AJB:2002
Characterization of potential ethylene-producing rhizosphere bacteria of Striga-infested maize and sorghum Olubukola O. Babalola, Elie O. Osir and Abiodun I. Sanni Short Communication Three rhizosphere bacteria, Pseudomonas sp., Enterobacter sakazakii andKlebsiella oxytoca, were analyzed for genetic variation. DNA fingerprint patterns of the three bacteria were markedly different when amplified with different primers. In total, 68 bands were produced by the three primers, 62 of which where variable. The number of polymorphic RAPD loci per isolate ranged from one to 13. Cluster analysis indicated that E. sakazakii and K. oxytoca are the most closely related of the three. Key words: Bacteria, RAPD-PCR, Striga hermonthica. Academic Journals 2002 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/193B7056569 http://dx.doi.org/10.5897/AJB2002.000-013 en Copyright © 2002 Olubukola O. Babalola, Elie O. Osir and Abiodun I. Sanni
oai:academicjournals.org:AJB:79CA2B88674 2003-01-31T00:00:00Z AcademicJournals AJB AJB:2003
Actinorhizal, mycorhizal and rhizobial symbioses: how much do we know? Diaga Diouf,, Tahir A. Diop, and Ibrahima Ndoye, Minireview In this review, we discuss the recent progress in research on symbiotic association of rhizobia, Frankia and fungi with plant roots. We compare infection processes of symbiotic establishment; structure, functioning and molecular biology of the symbiotic organ including the regulation of genes implicated in rhizobial, actinorhizial and arbuscularmycorhizal symbioses. Key words: Symbiosis, nodule, mycorrhiza, symbiotic genes. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/79CA2B88674 http://dx.doi.org/10.5897/AJB2003.000-1001 en Copyright © 2003 Diaga Diouf,, Tahir A. Diop, and Ibrahima Ndoye,
oai:academicjournals.org:AJB:18B6E5D8681 2003-01-31T00:00:00Z AcademicJournals AJB AJB:2003
Effects of mixed nitrogen sources on biodegradation of phenol by immobilized Acinetobacter sp. strain W-17 Desouky Abd-El-Haleem, Usama Beshay, Abdou O. Abdelhamid , Hassan Moawad and Sahar Zaki Full Length Research Paper Using Ca-alginate immobilized cells of Acinetobacter sp. strain W-17, the effects of ammonium-N and nitrate-N on the biodegradation of phenol were investigated.Degradation experiments in three different culture media; minimal salts medium (MSM), simulated (SW) and modified simulated wastewater (MSW) were performed. With the freely suspended cells (cell dry weight 0.2 g/l), complete phenol (500 mg/l) degradation was achieved after incubation for 120 h. Using the immobilized cells, the time was reduced to 24 h in MSM medium, and 15 h in the MSW. The results also indicate thatstrain W-17 can tolerate to high concentrations of NH4+-N (63 mg/l) and NO3--N (1000 mg/l) without a significant loss in the phenol biodegradation rate. Moreover, the presence of 500 mg/l phenol in the MSW had no considerable effect on the removal of both ammonium-N and nitrate-N. Repeated use of immobilized cells revealed that they could be used as much as five times without loss of activity. Our findings could be extended to enhance biotreatment of phenol contamination in a variety of biological treatment processes. Key words: Phenol, biodegradation, immobilization, Acinetobacter, Ca-alginate, ammonium, nitrate. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/18B6E5D8681 http://dx.doi.org/10.5897/AJB2003.000-1002 en Copyright © 2003 Desouky Abd-El-Haleem, Usama Beshay, Abdou O. Abdelhamid , Hassan Moawad and Sahar Zaki
oai:academicjournals.org:AJB:A18F80E8687 2003-01-31T00:00:00Z AcademicJournals AJB AJB:2003
Diversity of indigeneous bradyrhizobia associated with three cowpea cultivars (Vigna unguiculata (L.) Walp.) grown under limited and favorable water conditions in Senegal (West Africa) Tatiana Krasova-Wade, , , Ibrahima Ndoye, , Serge Braconnier, Benoit Sarr, Philippe de Lajudie and Marc Neyra Full Length Research Paper The diversity of Bradyrhizobium strains nodulating three cowpea (Vigna unguiculataL. Walp.) cultivars in favorable and water-limited conditions occuring at flowering was analysed. PCR- Restriction Fragment Length Polymorphism (PCR-RFLP) analysis of 16S-23S rDNA intergenic spacer region (IGS) directly applied on 85 crushed nodules distinguished four genetic profiles, IGS types I, II, III and IV. The distribution of these IGS types according to water conditions and cowpea cultivars (B-21, TN 88-63 and Mouride) showed that nodulating strains appeared more diverse in water-limited condition. More than three quarters of prospected nodules presented the IGS type I. They were formed on all three cultivars and in both water conditions. Only a small part of nodules was distributed between the IGS type II, III and IV. Nodules showing the IGS types II and III were found mainly in limited conditions on TN 88-63 and Mouride cultivars, whereas nodules presenting the IGS type IV were collected only from cultivars B-21 and Mouride, in both water conditions. Strains corresponding to the different profiles were isolated. The phylogenetic analysis of 16S rRNA gene sequences showed that they belong to the genus, Bradyrhizobium. The sequence analysis of 16S-23S rDNA IGS revealed that the strains exhibiting IGS types II, III and IV were closely related to some Faidherbia albida isolates from Senegal. IGS type II can be assigned with at least 98% similarity to Bradyrhizobium genospecies IV. IGS types III and IV showed more than 96% similarity with genospecies VII and could belong to the same genospecies. IGS type I, the most frequent, exhibits low IGS similarity with reported sequences in the databases, and could represent a new genospecies. Key words: Bradyrhizobium, Vigna unguiculata, water-limited condition, PCR-RFLP, 16S rDNA, 16S-23S rDNA IGS. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/A18F80E8687 http://dx.doi.org/10.5897/AJB2003.000-1003 en Copyright © 2003 Tatiana Krasova-Wade, , , Ibrahima Ndoye, , Serge Braconnier, Benoit Sarr, Philippe de Lajudie and Marc Neyra
oai:academicjournals.org:AJB:3F7BA308693 2003-01-31T00:00:00Z AcademicJournals AJB AJB:2003
Pre-harvest deterioration of Sour sop (Annona muricata) at Ibadan Southwestern Nigeria and its effect on nutrient composition N. A. Amusa, O. A. Ashaye, M. O. Oladapo and O.O. Kafaru Short Communication The etiology of pre-harvest deterioration of Soursop (Annona muricata) fruit in Ibadan, southwestern Nigeria and the effects on its nutrient composition was investigated. Four fungal pathogens including Botryodiplodia theobromae, Fusariumsp., Rhizopus stolonifer and Aspergillus niger were found associated with the pre-harvest deteriorating soursop . B. theobromae was the most prevalent and the most pathogenic inducing rot of 75 mm in diameter within four days of inoculation. There was a remarkable reduction in carbohydrate and protein contents of the fungal infected fruits while all other nutrients and mineral assayed were higher in the infected fruits than the non-infected ones. Key words: Annona muricata, fungal pathogens, pre-harvest deterioration. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3F7BA308693 http://dx.doi.org/10.5897/AJB2003.000-1004 en Copyright © 2003 N. A. Amusa, O. A. Ashaye, M. O. Oladapo and O.O. Kafaru
oai:academicjournals.org:AJB:AA983B68699 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
The molecular initiation and subsequent acquisition of disease resistance in plants Emma Wanjiru Gachomo, Olusola Olusoji Shonukan and Simeon Oloni Kotchoni Minireview Interactions between disease resistance (R) genes in plants and their corresponding pathogen avirulence (Avr) genes are the key determinants of whether a plant is susceptible or resistance to a pathogen attack. Evidence has emerged that these gene-for-gene interactions in the perception of pathogenic invasions and development of acquired resistance in plants involve different molecular and hormonal transduction pathways, which are still poorly understood. It has become apparent that plants actively produce several phytohormones such as ethylene, jasmonate, salicylic acid, and reactive oxygen intermediates prior to upregulation of R genes. The physiological role of these molecules in plant resistance to pathogens is beginning to attract attention. The use of transgenic plants in recent attempts, including development of mutants with altered R genes, has provided new insights into the mechanisms involved in pathogen perception, signal transduction and subsequent resistance to disease in plants. This review tries to summarize current knowledge of pathogen-related genes in plants, and how they can be use to improve disease resistance in agronomically valuable plants. It also describes the molecular basis of defense mechanisms in plants under pathogen attack. Key words: Avr, resistance gene, hypersensitivity, pathogenesis-related proteins, transgenic, plant-defense. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/AA983B68699 http://dx.doi.org/10.5897/AJB2003.000-1005 en Copyright © 2003 Emma Wanjiru Gachomo, Olusola Olusoji Shonukan and Simeon Oloni Kotchoni
oai:academicjournals.org:AJB:39B819B8703 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Variations in fatty acid proportions during desiccation of Telfairia occidentalis seeds harvested at physiological and agronomic maturity Nkang A, Omokaro D, Egbe A and Amanke, G Full Length Research Paper The effect of desiccation on lipid content, fatty acid composition and the antioxidative enzymic capacity was investigated in seeds of Telfairia occidentalis, harvested at physiological and agronomic maturity. Seeds were dried at 5 and 28 oC, environments that induced different drying and metabolic rates. Desiccation of seeds was associated with decreased antioxidative enzymic capacity (of peroxidase and polyphenoloxidase), and thus increased likelihood of free radical attack and decreased viability (germinability). Agronomically mature seeds contained predominantly saturated fatty acids (tridecanoic), with very low levels of the major fatty acids of edible oilseeds (palmitic, stearic or the unsaturated C18 fatty acids). There was increased accumulation of the mono-unsaturated (oleic) and polyunsaturated (linoleic) fatty acids when seeds were dried at 28 oC and moisture contents have reduced to about 42 % or lower. In contrast, seeds dried at 5 oC maintained high levels of saturated fatty acids and lower levels of monounsaturated or polyunsaturated fatty acids. Results suggest the need to develop different post-harvest protocols for seed storage, and for processing T.occidentalis to lsquo;improversquo; the seed fatty acid profile as an oilseed for human and animal food. Key words: Agronomic maturity, desiccation, fatty acid, lipid peroxidation, oilseed. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/39B819B8703 http://dx.doi.org/10.5897/AJB2003.000-1006 en Copyright © 2003 Nkang A, Omokaro D, Egbe A and Amanke, G
oai:academicjournals.org:AJB:759E6BA8708 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
The use of a novel phage-based technology as a practical tool for the diagnosis of tuberculosis in Africa Tracy Seaman, Andre Trollip, Richard Mole and Heidi Albert Full Length Research Paper Sub-Saharan Africa has experienced a significant increase in tuberculosis cases in recent years, fuelled by high rates of TB-HIV co-infection in the region. The diagnosis of tuberculosis is based largely on clinical assessment, sputum smear microscopy and chest radiography. Although smear microscopy is useful for detecting the most infectious cases, a significant portion of cases are negative on sputum smears, making diagnosis more difficult. New tests are urgently needed. The FASTPlaqueTB test, a bacteriophage-based method, has been evaluated in several studies in Africa and elsewhere. Studies in South Africa and Pakistan reported that between half and two-thirds of smear-negative culture-positive TB cases were detected by theFASTPlaqueTB test within 2 days. This suggests a beneficial role for this test in the early diagnosis of clinically suspected smear-negative cases. The same technology has been applied to develop a rapid test to indicate multi-drug resistant TB,FASTPlaqueTB-MDRi. This test gave equivalent results to conventional drug susceptibility methods, but with more rapid results. The tests are simple to perform and require no specialised equipment, making the technology suitable for widespread implementation. Key words: Tuberculosis, bacteriophage, diagnostic test, phage amplification technology, multi-drug resistance, drug susceptibility test. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/759E6BA8708 http://dx.doi.org/10.5897/AJB2003.000-1007 en Copyright © 2003 Tracy Seaman, Andre Trollip, Richard Mole and Heidi Albert
oai:academicjournals.org:AJB:CC3DD488712 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Relationship between genetic similarity and some productive traits in local chicken strains Bahy Ahmed Ali, Mohamed Morsy Mohamed Ahmed, Osama Mahmoud Aly Short Communication Random amplified polymorphic DNA (RAPD) technique was applied to detect genetic similarity between five local chicken strains that have been selected for eggs and meat production in Egypt. Based on six oligonucleotide primers, the genetic similarity between the egg-producing strains (Anshas, Silver Montazah and Mandarah) ranged from 72.4 to 85.4%. While the genetic similarity between the two chicken strains selected for meat production (Baheij and El-Salam) is 86.9%. Key words: Chicken, local strains, RAPD-PCR, genetic similarity. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/CC3DD488712 http://dx.doi.org/10.5897/AJB2003.000-1008 en Copyright © 2003 Bahy Ahmed Ali, Mohamed Morsy Mohamed Ahmed, Osama Mahmoud Aly
oai:academicjournals.org:AJB:C55E9F48715 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Genetic diversity in cowpea [Vigna unguiculata (L.) Walp.] varieties determined by ARA and RAPD techniques Laiuml;ty Fall, Diaga Diouf, Mame Arama Fall-Ndiaye , Franccedil;ois Abaye Badiane and Mamadou Gueye Short Communication Cowpea, Vigna unguiculata (L.) Walp. presents phenotypical variabilities and in order to study the genetic diversity of cultivated Senegalese varieties, two experimental approaches were used. First, a physiological characterization based on nitrogen fixation was used to assess cowpea breeding lines. Inoculation with two Bradyrhizobiumstrains (NGR234 and ISRA312), showed a difference in nitrogen fixation potential between the cowpea varieties. Diongoma is the highest nitrogen fixing variety, whereas Mouride is the lowest. The second approach employed genetic characterization based on DNA polymorphism to screen. Results suggest that random amplified polymorphic DNA (RAPD) technology can be used to reorganize the national germplasm in order to eliminate the putative duplicates, and to identify elite varieties. Key words: Vigna unguiculata, nitrogen fixation, cowpea, molecular markers, RAPD. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/C55E9F48715 http://dx.doi.org/10.5897/AJB2003.000-1009 en Copyright © 2003 Laiuml;ty Fall, Diaga Diouf, Mame Arama Fall-Ndiaye , Franccedil;ois Abaye Badiane and Mamadou Gueye
oai:academicjournals.org:AJB:12C840C32267 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
The Biochemical Society of Kenya Daniel Masiga Editorial Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/12C840C32267 http://dx.doi.org/10.5897/AJB2004.000-2021 en Copyright © 2003 Daniel Masiga
oai:academicjournals.org:AJB:3D2922332287 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Opportunities in Africa for training in genome science Daniel K. Masiga and Raphael D. Isokpehi Perspective Genome science is a new type of biology that unites genetics, molecular biology, computational biology and bioinformatics. The availability of the human genome sequence, as well as the genome sequences of several other organisms relevant to health, agriculture and the environment in Africa necessitates the development and delivery of several types and levels of training that will enhance the use of genome data and the associated computational resources. A survey of initiatives that provide opportunities for training in genome science is presented. Current efforts to increase the ability of African scientists to computationally process and analyse genomic and post-genomic data have the potential to produce excellent scientists who perform cutting-edge, hypothesis-based research, and who will accelerate the continentrsquo;s scientific and technological development. Key words: Bioinformatics, collaboration, computational biology, genome science. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3D2922332287 http://dx.doi.org/10.5897/AJB2004.000-2022 en Copyright © 2003 Daniel K. Masiga and Raphael D. Isokpehi
oai:academicjournals.org:AJB:5E14DF632314 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Research communications in the 21st century Nyerhovwo J. Tonukari Perspective Scientific inquiry thrives only in a society that fosters the free flow of ideas and information. The power of online (internet) publication in democratizing science and incorporating scientists from developing countries into the scientific community is profound. The desired and obvious properties of scientific publishing such as accessibility, economy, quality, innovation, and retrieval can be more readily achieved with electronic methods. Online publication is much cheaper and faster, and that is major reason Africa should embrace the open access model for research communication. An open access African journal (the African Journal of Biotechnology) is evaluated. Key words: Open access, African Journal of Biotechnology, research communications. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/5E14DF632314 http://dx.doi.org/10.5897/AJB2004.000-2023 en Copyright © 2003 Nyerhovwo J. Tonukari
oai:academicjournals.org:AJB:EACB56132327 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Agricultural genomics and sustainable development: perspectives and prospects for Africa Jesse Machuka Review The genomes of various organisms have now been fully sequenced, including human and representative microbial, insect, animal and plant genomes. The research challenge in the post-genome era is to establish how genes and proteins function to bring about changes in phenotype. Some of these phenotypes, and products obtainable through modern biotechnology, are of crucial importance within the context of sustainable development of African economies. The greatest ultimate impact will be in agricultural genomics, especially for marker assisted selection and breeding programs in crop and animal agriculture, development of animal disease diagnostics and vaccines, crop genetic engineering to overcome abiotic and biotic stresses and for improvement of the nutritional quality of major food staples. It is imperative that African countries become key players in the ldquo;gene revolutionrdquo; since the cost of leaving them behind may be higher than the cost of empowering them to become players in mastering and benefiting from biotechnology. This paper highlights the potential impact of the latest advances in modern biotechnology, including genomics and bioinformatics, on sustainable development, in line with the goals of the New Partnership for Africa#39;s Development (NEPAD). These include acceleration of economic growth, eradication of widespread and severe poverty and efforts to halt the marginalization of Africa in the globalization process. Key words: Genomics, modern biotechnology, agriculture, sustainable development, Africa. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/EACB56132327 http://dx.doi.org/10.5897/AJB2004.000-2024 en Copyright © 2003 Jesse Machuka
oai:academicjournals.org:AJB:2687D2032340 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Plant genetic resources: Advancing conservation and use through biotechnology N. Kameswara Rao Full Length Research Paper Conservation and sustainable use of genetic resources is essential to meet the demand for future food security. Advances in biotechnology have generated new opportunities for genetic resources conservation and utilization. Techniques like in vitro culture and cryopreservation have made it easy to collect and conserve genetic resources, especially of species that are difficult to conserve as seeds. While technologies like enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) have provided tools that are more sensitive and pathogen specific for seed health testing, tissue culture methods are now widely applied for elimination of systemic diseases such as viruses for safe exchange of germplasm. Molecular markers are increasingly used for screening of germplasm to study genetic diversity, identify redundancies in the collections, test accession stability and integrity, and resolve taxonomic relationships. The technology is also expanding the scope of genetic resources utilization. Key words: Biotechnology, conservation, plant genetic resources. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/2687D2032340 http://dx.doi.org/10.5897/AJB2004.000-2025 en Copyright © 2003 N. Kameswara Rao
oai:academicjournals.org:AJB:76F44A332351 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Estimates of outcrossing rates in Moringa oleifera using Amplified fragment length polymorphism (AFLP) Muluvi GM, Sprent JI, Odee D and Powell W Full Length Research Paper The mating system in plant populations is influenced by genetic and environmental factors. Proper estimates of the outcrosing rates are often required for planning breeding programmes, conservation and management of tropical trees. However, althoughMoringa oleifera is adapted to a mixed mating system, the proportion of selfing has not been previously estimated. The current work therefore, shows the use of AFLP markers in a mating system study of M. oleifera seed orchard. Data revealed a mixed mating system with a multilocus outcrossing rate (tm) of 0.74. It further demonstrated that AFLP markers, though dominant with a lower information content than co-dominant markers are adequate for the study of the mating system in plant populations. The 26% selfing observed in M. oleifera can lead to overestimation of the proportion of additive genetic variance and appropriate adjustments are therefore required. However, the presence of selfing as well as early sexual maturity (6 months to 1 year) in M. oleiferaprovides an opportunity for developing inbred lines and hybridisation. Additionally, in designing M. oleifera seed orchards, randomisation and minimum distance between related individuals need to be worked out to maximise cross-fertilisation among unrelated clones and minimise selfing or mating among related ramets. Key words: Moringa oleifera, mating system, outcrossing rates, amplified fragment length polymorphism. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/76F44A332351 http://dx.doi.org/10.5897/AJB2004.000-2026 en Copyright © 2003 Muluvi GM, Sprent JI, Odee D and Powell W
oai:academicjournals.org:AJB:5E2BE3F32358 2003-02-28T00:00:00Z AcademicJournals AJB AJB:2003
Comparative genetics of alcoholism in the Kenyan populations Korir Elena Doudoladova, Ochieng David and Ndiritu Douglas Full Length Research Paper Hepatic alcohol dehydrogenase and aldehyde dehydrogenase are major enzymes in the metabolism of exogenous ethanol. These enzymes are polymorphic and are involved in alcohol drinking and risk of alcoholism in some world populations. Three hundred and seventy one samples of hair root lyzates from five Kenyan communities were screened for ADH 2, ADH 3 and ALDH 2 polymorphisms via isoelectric focusing. Additional information on alcohol drinking behaviour, alcohol intake, frequency of alcohol drinking, preference of alcoholic drinks, and alcohol dependence was collected via interview and questionnaire. SAS JPIN statistical program was used to analyze obtained data using chi-square, Anova and t-tests. The results showed that ADH 2*2, ADH 3*1 and ALDH 2*2 alleles do not have protective properties against risk of alcoholism in the selected Kenyan populations. Other factors than ADH and ALDH polymorphisms interfered in the protective mechanism of the latter alleles against excessive alcohol drinking. Key words: Alcohol, ADH, ALDH, polymorphism, alcohol drinking, alcoholism. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/5E2BE3F32358 http://dx.doi.org/10.5897/AJB2004.000-2027 en Copyright © 2003 Korir Elena Doudoladova, Ochieng David and Ndiritu Douglas
oai:academicjournals.org:AJB:42166218746 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Molecular phylogeny of Fusarium species by AFLP fingerprint Mohmed A. Abdel-Satar, Mohmed. S. Khalil, I. N. Mohmed, Kamel A. Abd-Elsalam, and Joseph A. Verreet Full Length Research Paper The high-resolution genotyping method of amplified fragment length polymorphism (AFLP) analysis was used to study the genetic relationships within and between natural populations of five Fusarium spp. AFLP templates were prepared by the digestion ofFusarium DNA with EcoRI and MseI restriction endonucleases and subsequent ligation of corresponding site-specific adapters. An average of 44 loci was assayed simultaneously with each primer pair and DNA markers in the range 100 to 500 bp were considered for analysis. A total of 80 AFLP polymorphic markers were obtained using four primer combinations, with an average of 20 polymorphic markers observed per primer pair. UPGMA analyses indicated 5 distinct clusters at the phenon line of 30% on the genetic similarity scale corresponding to the 5 taxa. The similarity percent of each group oscillated between 87 and 97%. The phenetic dendrogram generated by UPGMA as well as principal coordinate analysis (PCA) grouped all of the Fusariumspp. isolates into five major clusters. No clear trend was detected between clustering in the AFLP dendrogram and geographic origin, host genotype of the tested isolates with a few exceptions. The results of the present study provide evidence of the high discriminatory power of AFLP analysis, suggesting the possible applicability of this method to the molecular characterization of Fusarium. Key words: AFLP, Fusarium, molecular phylogeny, selective amplification. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/42166218746 http://dx.doi.org/10.5897/AJB2003.000-1010 en Copyright © 2003 Mohmed A. Abdel-Satar, Mohmed. S. Khalil, I. N. Mohmed, Kamel A. Abd-Elsalam, and Joseph A. Verreet
oai:academicjournals.org:AJB:625D95E8750 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Biodeterioration of the African star apple (Chrysophylum albidum) in storage and the effect on its food value N. A. Amusa, O.A. Ashaye and M. O. Oladapo Full Length Research Paper The biodeterioration of the African star apple fruits in storage was investigated at Ibadan, southwestern Nigeria. Eight fungal isolates were found associated with the deteriorating fruits. The fungi are Botryodiplodia theobromae, Rhizopus stolonifer,Aspergillus niger, A. tamarii, A. flavus, Fusarium spp, Penicilium spp andTrichoderma spp. All the fungal isolates were pathogenic on the star apple fruits with the exception of Trichoderma spp. The African star apple fruits stored for up to 5 days were associated with severe fungal infections and had significantly reduced crude protein, crude fat and moisture content while dry matter, potassium, calcium and sodium increased compared to the freshly harvested fruits. Key words: Chrysophilum albidum, biodeterioration, fungal pathogens, storage. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/625D95E8750 http://dx.doi.org/10.5897/AJB2003.000-1011 en Copyright © 2003 N. A. Amusa, O.A. Ashaye and M. O. Oladapo
oai:academicjournals.org:AJB:A9470428757 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Production of alkaline protease by Teredinobacter turnirae cells immobilized in Ca-alginate beads Usama Beshay Full Length Research Paper The conditions for immobilizing the new alkaline protease-producing bacteria strainTeredinobacter turnirae by entrapment in calcium alginate gel were investigated. The influence of alginate concentration (20, 25 and 30 g/l) and initial cell loading (ICL) on enzyme production were studied. The production of alkaline protease improved significantly with increasing alginate concentration and reached a maximum enzyme yield of 8000 U/ml at 25 g/l alginate concentration. This was about 176.8% higher than that obtained by free cells (2890 U/ml). The immobilized cells produced alkaline protease consistently over 5 repeated cycles and reached a maximal value of 9000 U/ml on the third cycle. This was 311.4% (3.11-fold) as compared with the control (free cells). Simple mass balance analysis was applied to describe the growth and the protease production behaviour of both fractions the cells in free form and the entrapped in Ca-alginate beads. Scanning electron microscope studies indicated the internal distribution pattern of the cells encapsulated in Ca-alginate beads. The results presented in this paper show the potential for using immobilized T. turnirae cells in Ca-alginate for the production of a novel alkaline protease. Key words: Alkaline protease, Ca-alginate, immobilization, Teredinobacter turnirae, repeated batch. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/A9470428757 http://dx.doi.org/10.5897/AJB2003.000-1012 en Copyright © 2003 Usama Beshay
oai:academicjournals.org:AJB:52484338765 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
A capillary electrophoretic method for isolation and characterization of grape xylem proteins Ashok K. Jain and Sheikh M. Basha Full Length Research Paper European (Vitis vinifera) and American (Vitis labrusca) grape species succumb to a bacterial disease known as Piercersquo;s Disease (PD). In contrast, muscadine grape genotypes (Vitis rotundifolia) are tolerant/resistant to PD. This is due to the unique biochemical composition of muscadine xylem. However, because of low protein concentration, conventional methods such as low-pressure chromatography and PAGE are unsuitable for grape xylem protein characterization. In addition, these procedures are tedious, time-consuming and require large amount of sample. This study reports a procedure for isolating and separating proteins from muscadine and bunch grape xylem tissue. The procedure consists of separation of xylem from cortex and phloem, removal of pigments and other gummy substances from xylem with ethanol: ethylacetate (2:1) and subsequent Capillary Electrophoretic (CE) analysis of xylem protein extracts to achieve desired resolution. Number of peaks, peak height and areas, retention time and baseline position were used to compare resolution and study the effect of sample and separation buffer. Xylem tissue proteins extracted with 0.05% sodium borate buffer (pH 8.3) and subjected to CE using 1.2% sodium borate (pH 8.3) as a separation buffer were found to yield most satisfactory resolution of grape xylem proteins. The data obtained by CE were consistent and reproducible, and hence, is well suited to obtain excellent resolution of xylem tissue protein for identifying differences in protein composition among the grape genotypes. Key words: Capillary electrophoresis, grape, Vitis, xylem, Piercersquo;s disease, protein. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/52484338765 http://dx.doi.org/10.5897/AJB2003.000-1013 en Copyright © 2003 Ashok K. Jain and Sheikh M. Basha
oai:academicjournals.org:AJB:0F91E5332390 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Plant gene technology: social considerations Berhanu Abraha Tsegay Perspective The genetic modification of plants by gene technology is of immense potential benefits, but there may be possible risks. The advantages and social concerns of plant gene technology are discussed. Key words: Gene technology, genetically modified plant, agriculture. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/0F91E5332390 http://dx.doi.org/10.5897/AJB2004.000-2028 en Copyright © 2003 Berhanu Abraha Tsegay
oai:academicjournals.org:AJB:9AFCC6032406 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Microcystis aeruginosa: source of toxic microcystins in drinking water Oberholster PJ, Botha A-M and Grobbelaar JU Review Cyanobacteria are one of the earthrsquo;s most ancient life forms. Evidence of their existence on earth, derived from fossil records, encompasses a period of some 3.5 billion years in the late Precambrian era. Cyanobacteria are the dominant phytoplanton group in eutrophic freshwater bodies worldwide. They have caused animal poisoning in many parts of the world and may present risks to human health through drinking and recreational activity. Cyanobacteria produce two main groups of toxin namely neurotoxins and peptide hepatotoxins. They were first characterized from the unicellular species, Microcystis aeruginosa, which is the most common toxic cyanobacterium in eutrophic freshwater. The association of environmental parameters with cyanobacterial blooms and the toxicity of microcystin are discussed. Also, the synthesis of the microcystins, as well as the mode of action, control and analysis methods for quantitation of the toxin is reviewed. Key words: Cyanobacteria, microcystins, mcyB gene, PCR-RFLP. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/9AFCC6032406 http://dx.doi.org/10.5897/AJB2004.000-2029 en Copyright © 2003 Oberholster PJ, Botha A-M and Grobbelaar JU
oai:academicjournals.org:AJB:C6BFA0232421 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Screening cowpea [Vigna unguiculata (L.) Walp.] varieties by inducing water deficit and RAPD analyses Franccedil;ois Abaye Badiane, Diaga Diouf, Djibril Saneacute;, Omar Diouf,Venceslas Goudiaby and Nicolas Diallo, Full Length Research Paper The effects of water deficit induced by polyethylene glycol-6000 on some cowpea varieties, which belong to the national germplasm in Senegal are reported. Our results showed that, the length of the epicotyl was not affected by water deficit but the length of primary root was influenced only in Mouride variety. Water deficit influenced mostly the number of lateral roots. The 985 variety showed a great increase of its lateral root numbers and could be considered a drought tolerant variety. In contrast, the IT81D-1137 variety is very sensitive to water deficit because its lateral root number were reduced 3.8 fold compared to the control. These physiological studies were complemented by analyzing the genetic diversity of these varieties with random amplified polymorphic DNA (RAPD). The RAPD analysis suggested that the samples were also genetically diverse. Key words: Vigna unguiculata, drought tolerance, PEG, RAPD. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/C6BFA0232421 http://dx.doi.org/10.5897/AJB2004.000-2030 en Copyright © 2003 Franccedil;ois Abaye Badiane, Diaga Diouf, Djibril Saneacute;, Omar Diouf,Venceslas Goudiaby and Nicolas Diallo,
oai:academicjournals.org:AJB:009B9F732443 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Effects of sulphuric acid, mechanical scarification and wet heat treatments on germination of seeds of African locust bean tree, Parkia biglobosa B. L. Aliero Short Communication Effects of different treatment methods on the germination of seeds of Parkia biglobosa(mimosaceae) were carried out. Prior treatment of seeds with sulphuric acid, wet heat and mechanical scarification were found to induce germination of the dormant seeds. These methods could be applied to raise seedlings of the plant for field propagation. Key words: Scarification, germination, seeds, Parkia biglobosa Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/009B9F732443 http://dx.doi.org/10.5897/AJB2004.000-2031 en Copyright © 2003 B. L. Aliero
oai:academicjournals.org:AJB:066490E32452 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Enhancement of the feeding value of some agro-industrial by-products for laying hens after their solid state fermentation with Trichoderma viride Eustace A. Iyayi and Zaid A. Aderolu Full Length Research Paper This study with some agro-byproducts was carried out to provide information on the use of fermentation by-products; brewerrsquo;s dried grains (BDG), rice bran (RB), palm kernel meal (PKM) and corn bran (CB). Changes in the nutrient compositions of some selected agro industrial by-products on biodegradation with Trichoderma viride and their feeding value as an energy source for layers were investigated. The protein in BDG, RB, PKM and CB increased by 87, 68, 32 and 61%, respectively, when they were fermented with the fungi for 14 days. At the same time, the fiber in the by-products decreased by 35.00, 40.00, 36.50 and 37.50%, respectively with a corresponding increase of 49.00, 37.00, 9.00 and 5.50% in the level of soluble sugars. The energy in the biodegraded by-products increased by 6.30, 5.00, 9.00 and 18.50%, respectively. In a feeding trial with layers, 50% of the maize in a standard commercial diet was replaced with biodegraded BDG, RB and PKM. Birds on the BDG and RB diets had significantly (Plt;0.05) higher hen day production than those on the other diets. Diets in which the biodegraded by-products replaced maize produced lower cost of egg production than the standard commercial diet. Of the test diets, BDG gave the lowest cost of US$0.38 per tray of eggs (30 eggs) compared with US$0.53 for the commercial diet. Results of the study showed that fungal biodegradation of the agro industrial by-products can enhance their nutritional status. Using such by-products to feed layers spared half of the maize in the diet and produced better laying performance. Key words: Agro by-products, fungal fermentation, nutrient improvement, poultry feeding. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/066490E32452 http://dx.doi.org/10.5897/AJB2004.000-2032 en Copyright © 2003 Eustace A. Iyayi and Zaid A. Aderolu
oai:academicjournals.org:AJB:3DF9F5F32467 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Changes in the cellulose, sugar and crude protein contents of agro-industrial by-products fermented with Aspergillus niger, Aspergillus flavus and Penicillium sp. Eustace A. Iyayi Short Communication Changes in the protein, sugar and cellulose of three agro-industrial by-products after fermentation with Aspergillus niger, Aspergillus flavus and Penicillium sp. in solid state were determined. Cellulose was significantly reduced (Plt;0.05) in all the agro wastes by all the fungi after 14 days. Highest percentage reduction was achieved by A.niger in all the agro wastes; 36.51% for wheat offal (WO), 35.87% for brewers dried grain (BDG) and 35.80% for maize offal (MO). There was a corresponding build up of all the soluble sugars in the substrate up to 14 days. Beyond day 14, the sugar level began to fall and there was no more significant degradation of the cellulose. The crude protein of the BDG, MO and WO increased significantly (Plt;.0.05). After 14 days, the highest percentage increase in protein (41%) was obtained in WO inoculated with A.niger. Results of the study indicate the possibility of enhancing the feeding value of these by-products by a simple, inexpensive and easily adaptable technique. Key words: Cellulose, sugar, protein, changes, fermentation, fungi. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3DF9F5F32467 http://dx.doi.org/10.5897/AJB2004.000-2033 en Copyright © 2003 Eustace A. Iyayi
oai:academicjournals.org:AJB:91CF47432474 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Identification of exopolysaccharides-producing lactic acid bacteria from Burkina Faso fermented milk samples Aly Savadogo, Cheik A. T. Ouattara, Paul W. Savadogo, Nicolas Barro, Aboubacar S. Ouattara and Alfred S. Traoreacute; Full Length Research Paper Spacer region between 16S and 23 S rRNA genes of thirteen lactic acid bacteria strains from Burkina Faso fermented milk samples were amplified by the polymerase chain reaction (PCR). Lactobacillus delbrueckii, Lactobacillus acidophilus, Lactobacillus fermentum, Streptococcus thermophilus, Pediococcus spp, Leuconostoc mesenteroides subsp mesenteroides were identified. The Lactobacillus group was the predominant bacteria. Plasmids identified ranged between 2000 and 4000 bp. Exopolysaccharides (EPS) production varied from 181 mg/l and 814 mg/l, monomer analysis showed that glucose and galactose were predominant. Key words: Lactic acid bacteria, fermented milk, PCR, exopolysaccharides. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/91CF47432474 http://dx.doi.org/10.5897/AJB2004.000-2034 en Copyright © 2003 Aly Savadogo, Cheik A. T. Ouattara, Paul W. Savadogo, Nicolas Barro, Aboubacar S. Ouattara and Alfred S. Traoreacute;
oai:academicjournals.org:AJB:74DD55732488 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Colletotrichum circinans and Colletotrichum coccodes can be distinguished by DGGE analysis of PCR-amplified 18S rDNA fragments Olajire Fagbola+ and Mathew M. Abang Full Length Research Paper The rDNA 18S region of Colletotrichum circinans and C. coccodes was amplified by PCR to evaluate this DNA region as a tool for species delineation. PCR amplification of the 18S of both species produced 1.65 Kb long fragments that covered most of the entire 18S rDNA molecule. DGGE analysis of the amplified fragments distinguished C.circinans from C. coccodes isolates. This result provides molecular evidence that supports the current treatment of C. circinans as a species distinct from C. coccodes, in spite of the failure of previous attempts at genetic differentiation of the two species based on RFLP analysis of the rDNA ITS region. Key words: DGGE, Colletotrichum circinans, Colletotrichum coccodes, molecular differentiation, species delineation. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/74DD55732488 http://dx.doi.org/10.5897/AJB2004.000-2035 en Copyright © 2003 Olajire Fagbola+ and Mathew M. Abang
oai:academicjournals.org:AJB:11A6B8332497 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Isolation of a kernel oleoyl-ACP thioesterase gene from the oil palm Elaeis guineensis Jacq. Omorefe Asemota, Cha Tye San and Farida H. Shah Short Communication Thioesterases play a central role in determining chain lengths of fatty acids in oil storage tissues and have been isolated from a number of plant sources. While in some species enzymes that are specialized for the predominant fatty acids in the tissues examined have been found, in others, enzymes that are active over a broad range were observed. We have isolated a cDNA clone from the developing kernel of the oil palm Elaeis guineensis which encodes a thioesterase enzyme. Its highest homology was to theBrassica napus oleoyl-ACP thioesterase with which it had 72% homology at the nucleotide level, over the coding region examined, and 83% identity (90% positives) at the amino acid level. Key words: Elaeis guineensis, kernel, oleoyl-ACP thioesterase, cDNA. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/11A6B8332497 http://dx.doi.org/10.5897/AJB2004.000-2036 en Copyright © 2003 Omorefe Asemota, Cha Tye San and Farida H. Shah
oai:academicjournals.org:AJB:C0D091332518 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Dockovdia cookarum infection and the prosobranch gastropod Lanistes libycus host in Omi Stream, Ago-Iwoye, south-western, Nigeria O. M. Agboladeand A. B. Odaibo Full Length Research Paper Dockovdia cookarum infection was studied in relation to the abundance and size classes of Lanistes libycus from Omi Stream, Ago-Iwoye, Nigeria, between September 1997 and June 1998. 57.6% of the 262 L. libycus recorded were collected during periods of heavy rainfall. 17.2% (45) of the L. libycus examined had D. cookarum infection. The water mite prevalences were higher in rainy season than in dry season, and ranged between 3.0% and 44.4% monthly. L. libycus in 21-30 mm size class had the highest prevalence (73.3%). Intensity of infection was higher in rainy season than in dry season, and ranged between 1 and 6 mite(s)/snail. 2.6% of the L. libycus specimens in the 21-30 mm size class had concurrent D. cookarum andChaetogaster limnaei infections. Key words: Dockovdia cookarum, water mites, Lanistes libycus, freshwater molluscs,Nigeria Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/C0D091332518 http://dx.doi.org/10.5897/AJB2004.000-2037 en Copyright © 2003 O. M. Agboladeand A. B. Odaibo
oai:academicjournals.org:AJB:4B9F62E32546 2003-03-31T00:00:00Z AcademicJournals AJB AJB:2003
Intestinal helminthiasis and urinary schistosomiasis in some villages of Ijebu North, Ogun State, Nigeria O. M. Agbolade, D. O. Akinboye and A. Awolaja Full Length Research Paper Intestinal helminthiasis and urinary schistosomiasis were studied between April and December, 2002, in six villages of Ijebu North Local Government, Ogun State, Nigeria. Faecal samples from 199 subjects were examined using direct smear and brine concentration methods. Urine samples were tested for haematuria and proteinuria using diagnostic reagent strips. Three helminthic parasites were identified in the faecal samples;Ascaris lumbricoides (62.8%), hookworm (16.6%) and Schistosoma haematobium(2.5%). None of the parasites was sex-dependent. A. lumbricoides had sup3;50% prevalence in all the age groups. The more common mixed infection was A. lumbricoides and hookworm (22.5%). The prevalences of haematuria and proteinuria were 7.5% and 15.7%, respectively. After single dose levamisole treatment, 16.8% of the subjects with intestinal helminths voided and submitted A. lumbridoides adult worms. Key words: Ascaris lumbricoides, hookworm, Schistosoma haematobium, haematuria, proteinuria, levamisole, Nigeria. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/4B9F62E32546 http://dx.doi.org/10.5897/AJB2004.000-2038 en Copyright © 2003 O. M. Agbolade, D. O. Akinboye and A. Awolaja
oai:academicjournals.org:AJB:0B382159100 2003-04-30T00:00:00Z AcademicJournals AJB AJB:2003
Acinetobacter: environmental and biotechnological applications Desouky Abdel-El-Haleem Minireview Among microbial communities involved in different ecosystems such as soil, freshwater, wastewater and solid wastes, several strains belonging to the genus of Acinetobacter have been attracting growing interest from medical, environmental and a biotechnological point of view. Bacteria of this genus are known to be involved in biodegradation, leaching and removal of several organic and inorganic man-made hazardous wastes. It is also well known that some of Acinetobacter strains produce important bioproducts. This review summarizes the usefulness and environmental applications of Acinetobacterstrains. Key words: Acinetobacter, biodegradation, xenobiotic, oil, heavy metals, bioproducts, lipases, polysaccharides. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/0B382159100 http://dx.doi.org/10.5897/AJB2003.000-1014 en Copyright © 2003 Desouky Abdel-El-Haleem
oai:academicjournals.org:AJB:4C024029106 2003-04-30T00:00:00Z AcademicJournals AJB AJB:2003
Functional and comparative analysis of expressed sequences from Diuraphis noxia infested wheat obtained utilizing the conserved Nucleotide Binding Site Lynelle Lacock, Chantal van Niekerk, Shilo Loots, Franco du Preez and Anna-Maria Botha Full Length Research Paper Russian wheat aphid (Diuraphis noxia, Morvilko; RWA) is a major pest on wheat, barley and other triticale in South Africa. Infestation by the RWA results in altered protein expression patterns, which is manifested as differential expression of gene sequences. In the present study, Russian wheat aphid resistant (Tugela DN, Tugela*5/SA2199, Tugela*5/SA463, PI 137739, PI 262660, and PI 294994) and susceptible triticale (Tugela) were infested and cDNA synthesized. A PCR based approach was utilized to amplify the nucleotide binding site conserved region to obtain expressed sequence tags (ESTs) with homology to resistance gene analogs (RGAs). The approach proved highly feasible when the isolation of RGAs is the main objective, since 18% of all obtained ESTs showed significant hits with known RGAs, when translated into their corresponding amino acid sequences and searched against the nonredundant GenBank protein database using the BLASTX algorithm. Key words: Resistance gene analogs, degenerate PCR, nucleotide-binding site-leucine rich repeat resistance genes, Aegilops tauschii. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/4C024029106 http://dx.doi.org/10.5897/AJB2003.000-1015 en Copyright © 2003 Lynelle Lacock, Chantal van Niekerk, Shilo Loots, Franco du Preez and Anna-Maria Botha
oai:academicjournals.org:AJB:42227749119 2003-04-30T00:00:00Z AcademicJournals AJB AJB:2003
PCR identification of Fusarium genus based on nuclear ribosomal-DNA sequence data Kamel A. Abd-Elsalam , , Ibrahim N. Aly, Mohmed A. Abdel-Satar, Mohmed S. Khalil and Joseph A. Verreet Full Length Research Paper We have developed two taxon-selective primers for quick identification of theFusarium genus. These primers, ITS-Fu-f and ITS-Fu-r were designed by comparing the aligned sequences of internal transcribed spacer regions (ITS) of a range ofFusarium species. The primers showed good specificity for the genus Fusarium, and the approximately 389-bp product was amplified exclusively. PCR sensitivity ranged from 100 fg to 10 ng for DNA extracted from Fusarium oxysporum mycelium. No amplification products were detected with PCR of DNA from Rhizoctonia solani andMacrophomina phaseolina isolates using these primers. The assay is useful for rapid identification of Fusarium spp. cultures. The application of these PCR methods for early diagnosis of the seedling and wilt disease of cotton needs to be studied further. Key words: rDNA, taxon-specific primer, Fusarium genus, Gossypium barbadense Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/42227749119 http://dx.doi.org/10.5897/AJB2003.000-1016 en Copyright © 2003 Kamel A. Abd-Elsalam , , Ibrahim N. Aly, Mohmed A. Abdel-Satar, Mohmed S. Khalil and Joseph A. Verreet
oai:academicjournals.org:AJB:A7E2BB99129 2003-04-30T00:00:00Z AcademicJournals AJB AJB:2003
Genetic comparisons of Egyptian date palm cultivars (Phoenix dactylifera L.) by RAPD-PCR Said Saad Soliman, Bahy Ahmed Ali, Mohamed Morsy Mohamed Ahmed Short Communication Random amplified polymorphic DNA technique was used to compare genetic material from four females date palm and four unknown male trees of Egyptian date palm. The genetic similarity between the four females date palm (Zaghloul, Amhat, Samany and Siwi) ranged from 87.5 to 98.9%. The banding profiles obtained suggested that both males 3 and 4 are genetically related to the four female cultivars. Key words: Date palm, cultivars, RAPD-PCR, genetic similarity. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/A7E2BB99129 http://dx.doi.org/10.5897/AJB2003.000-1017 en Copyright © 2003 Said Saad Soliman, Bahy Ahmed Ali, Mohamed Morsy Mohamed Ahmed
oai:academicjournals.org:AJB:6A5D3CD9136 2003-04-30T00:00:00Z AcademicJournals AJB AJB:2003
A home made kit for plasmid DNA mini-preparation Simeon Oloni KOTCHONI, Emma Wanjiru GACHOMO, Eriola BETIKU,Y and Olusola Olusoji SHONUKAN Short Communication Many methods have been used to isolate plasmid DNA, but some of them are time consuming especially when extracting a large number of samples. Here, we developed a rapid protocol for plasmid DNA extraction based on the alkaline lysis method of plasmid preparation (extraction at pH 8.0). Using this new method, a good plasmid preparation can be made in approximately one hour. The plasmids are suitable for any subsequent molecular applications in the laboratory. By applying the recommendations to avoid contaminations and to maximize the plasmid yield and quality during extraction, this protocol could be a valuable reference especially when analyzing a large number of samples. Key words: Plasmid extraction, PCR, restriction enzymes, sequencing, contamination. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/6A5D3CD9136 http://dx.doi.org/10.5897/AJB2003.000-1018 en Copyright © 2003 Simeon Oloni KOTCHONI, Emma Wanjiru GACHOMO, Eriola BETIKU,Y and Olusola Olusoji SHONUKAN
oai:academicjournals.org:AJB:D84CFC59144 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Bioinformatic tools and guideline for PCR primer design Kamel A. Abd-Elsalam Minireview Bioinformatics has become an essential tool not only for basic research but also for applied research in biotechnology and biomedical sciences. Optimal primer sequence and appropriate primer concentration are essential for maximal specificity and efficiency of PCR. A poorly designed primer can result in little or no product due to non-specific amplification and/or primer-dimer formation, which can become competitive enough to suppress product formation. There are several online tools devoted to serving molecular biologist design effective PCR primers. This review intends to provide a guide to choosing the most efficient way to design a new specific-primer by applying current publicly available links and Web services. Also, the purpose here is to provide general recommendations for the design and use of PCR primers. Key words: Bio-computing, primer design, web-based resources. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/D84CFC59144 http://dx.doi.org/10.5897/AJB2003.000-1019 en Copyright © 2003 Kamel A. Abd-Elsalam
oai:academicjournals.org:AJB:AEDFE519154 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Substrate Channelling and Energetics of Saccharomyces cerevisiae DSM 2155 Grown on Glucose in Fed-Batch Fermentation Process Olusegun Peter Akinyemi, Eriola Betiku+, and Bamidele Ogbe Solomon Full Length Research Paper Data collected during the high-cell-density cultivation of Saccharomyces cerevisiaeDSM 2155 on glucose in a simulated five-phase feeding strategy of fed-batch process, executed on the Universal BIoprocess CONtrol (UBICON) system using 150L bioreactor over a period of 24h have been analysed. The consistency of the data set was checked using both the available electron and carbon balances. Estimates of the true energetic yields and cell maintenance requirements were obtained through the application of a multivariate statistical procedure known as covariate adjustment technique. A low value of maintenance coefficient, me = 0.004h-1, and a high average value of the true biomass energetic yield, hmax = 0.745, were obtained for the bioreactor system, which showed that the organism was in no danger of ethanol produced during this cultivation. A simple model for estimating the distribution of substrate consumed between the fermentative and the respiratory pathways in the oxido-reductive process was developed based on the respiratory quotient (RQ) values. The fraction of substrate consumed for respiratory metabolic activities (qsresp/qs) was virtually 1.0 for the first three phases of the feeding strategy, which accounted for the first sixteen hours of the 24h operation. This was an indication that ethanol formation was avoided during this period. Key Words: Saccharomyces cerevisiae DSM 2155, available electron and carbon balances, fed-batch, respiratory quotient, true energetic yields, maintenance requirement. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/AEDFE519154 http://dx.doi.org/10.5897/AJB2003.000-1020 en Copyright © 2003 Olusegun Peter Akinyemi, Eriola Betiku+, and Bamidele Ogbe Solomon
oai:academicjournals.org:AJB:606F4C09160 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Biodegradation of Bonny light crude oil in soil microcosm by some bacterial strains isolated from crude oil flow stations saver pits in Nigeria A. I. Okoh Full Length Research Paper In an effort at developing an active indigenous bacterial consortium that could be of relevance in bioremediation of petroleum contaminated systems in Nigeria, four hydrocarbon degrading bacteria strains were isolated. Partial sequencing of the 16S rDNA of the isolates suggests that they are all strains of Pseudomonas aeruginosa. Axenic cultures of the isolates biodegraded Bonny light crude oil in soil microcosm. Amount of crude oil biodegraded in 15 days ranged significantly (P lt; 0.05) from 4.9% to 29.6%. Degradation rates and specific growth rates varied significantly (P lt; 0.05) between 0.049 and 0.351 day-1 and 0.017 and 0.028 hour-1 respectively. Major peak components of the oil were reduced by between 6.5% and 70.6%. It would appear thatoil degradation capability of axenic cultures of at least three of these isolates was not different from that of their consortium. Also, the multiple antibiotic resistance observed in the isolates is an important factor to consider in their eventual use in bioremediation exercises. Key words: Crude oil, soil microcosm, biodegradation. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/606F4C09160 http://dx.doi.org/10.5897/AJB2003.000-1021 en Copyright © 2003 A. I. Okoh
oai:academicjournals.org:AJB:0E21CA79166 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Genetic affinities of Fusarim spp. and their correlation with origin and pathogenicity Mohmed S. Khalil, Mohmed A. Abdel-Sattar, Ibrahim N. Aly, Kamel A. Abd-Elsalam, and Joseph A. Verreet Full Length Research Paper Random amplified polymorphic DNA (RAPD) analyses was used in combination with pathogenicity assays to study the taxonomic kinships among five Fusarium species. A total of 46 isolates of Fusarium spp. obtained from diseased cotton seedlings showing typical root rot and dampping-off symptoms were characterized. Of 10 primers tested, four primers produced polymorphic amplification patterns with taxon-specific bands, in addition to individual-specific bands. Genetic analysis indicated into 2 main clusters, with the minor cluster included all F. moniliforme and F. solani at the genetic similarity of GS=57.82%. The major cluster consisted of all F. oxysporum, F. avenaceum and F. chlamydosporum clustered at 71% similarity. There was no clear-cut relationship between clustering in the RAPD dendrogram, pathogenicity test and geographic origin of tested isolates. The results suggest that RAPD-PCR is a useful method for analysing genetic variation within and between Fusarium spp. Key words: DNA-fingerprinting, Fusarium chlamydosporum, genetic homology, RAPD-PCR. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/0E21CA79166 http://dx.doi.org/10.5897/AJB2003.000-1022 en Copyright © 2003 Mohmed S. Khalil, Mohmed A. Abdel-Sattar, Ibrahim N. Aly, Kamel A. Abd-Elsalam, and Joseph A. Verreet
oai:academicjournals.org:AJB:71865E99172 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Four gene introduction methods affect the shoot regeneration and localization of transgene expression in greenhouse stem explants and in vitro-grown chrysanthemum stem thin cell layers J. A. Teixeira da Silva and S. Fukai Full Length Research Paper Gene introduction method (GIM) affected shoot regeneration capacity (SRC) in standard and spray-type chrysanthemums. SRC was both cultivar and GIM-dependent in both in vitro and greenhouse stem explants, the former significantly higher than the latter. Sonication had an SRC-stimulating effect on in vitro explants. Other GIMs (Agrobacterium, biolistics, Agrolistics) had an SRC-inhibiting effect on greenhouse explants. Genotype-dependence of SRC was observed in both in vitro and greenhouse material. SRC is influenced by the explant and regeneration media, which should be modified if altered by the GIM. Shoots derived from all GIM treatments showed normal growth under in vitro and greenhouse conditions, and flowered normally. In addition, this study further shows that explant origin (in vitro versus greenhouse) and cultivar significantly affect the regeneration process, even when an optimized medium is utilized. The integration of the GUS transgene is also GIM-dependent, but in all cases is shown to occur in the venation. Keywords: Agroinfection, biolistics, explant survival, regeneration, sonication. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/71865E99172 http://dx.doi.org/10.5897/AJB2003.000-1023 en Copyright © 2003 J. A. Teixeira da Silva and S. Fukai
oai:academicjournals.org:AJB:2C9A4339179 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Molecular distribution of gypsy-like retrotransposons in cotton Gossypium Spp. Essam A. Zaki,y, and Abdel Ghany A. Abdel Ghany Full Length Research Paper PCR primers specific for conserved domains of the reverse transcriptase (RT) genes ofgypsy-like retrotransposons amplified their corresponding gene in two Gossypium barbadense cultivars. Analysis with the FASTA software showed a high DNA sequence homology to pine, gypsy LTR-retrotransposon. Using the PCR product as a hybridization probe, gypsy-like retrotransposons were detected in wild type species ofGossypium, suggesting that gypsy-like retrotransposons are present in the Gossypiumgenome. This supports the view that gypsy-like retrotransposons are major components of plant genomes. Our results suggest gypsy-like retrotransposons have played a fundamental role in the shaping and evolution of the Gossypium genome. Key words: Gossypium, gypsy, polyploidy, retroelements, retrotransposons, retroviruses, reverse transcriptase. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/2C9A4339179 http://dx.doi.org/10.5897/AJB2003.000-1024 en Copyright © 2003 Essam A. Zaki,y, and Abdel Ghany A. Abdel Ghany
oai:academicjournals.org:AJB:3913B579183 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
DNA Sequences of RAPD Fragments in the Egyptian cotton Gossypium barbadense Abdel Ghany A. Abdel Ghany and Essam A. Zaki,y, Full Length Research Paper Random Amplified Polymorphic DNAs (RAPDs) is a DNA polymorphism assay based on the amplification of random DNA segments with single primers of arbitrary nucleotide sequence. Despite the fact that the RAPD technique has become a very powerful tool and has found use in numerous applications, yet, the nature of molecular variation(s) uncovered by the RAPD technique is still unclear. The aim of the following study, therefore, was to investigate the molecular nature of RAPD DNA fragments in fourGossypium barbadense cultivars. Five RAPD DNA fragments, generated by improved RAPD-PCR technique, and representing polymorphic and nonpolymorphic bands were analyzed at the molecular level using DNA sequence analysis. Nonpolymorphic RAPD DNA fragments showed homologies to previously characterized plant structural genes.Comparative nucleotide sequence analysis of two comigrating nonpolymorphic fragments revealed that these two DNA sequences are highly similar to each other, indicating that similarity of fragment size is a good predicator of homology. Polymorphic RAPD DNA fragments, on the other hand, showed homologies to middle and high-repetitive DNA sequences. These results promote the initiative to integrate these RAPD markers in cotton breeding applications, and DNA fingerprinting. Key words: Gossypium, MITEs, RAPD-PCR, repetitive DNA, sequence similarity, retrotransposons. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3913B579183 http://dx.doi.org/10.5897/AJB2003.000-1025 en Copyright © 2003 Abdel Ghany A. Abdel Ghany and Essam A. Zaki,y,
oai:academicjournals.org:AJB:02459399191 2003-05-31T00:00:00Z AcademicJournals AJB AJB:2003
Effect of salt and drought stress on acid phosphatase activities in alfalfa (Medicago sativa L.) explants under in vitro culture A. A. Ehsanpour and F. Amini Short Communication Acid phosphatase is wildly found in plants. This enzyme has intra and extra cellular activity. For instance, it dephosphorylase organic phosphate and change it to inorganic phosphate. However, acid phosphatase activity is increased by salt and osmotic stress. In this experiments, calluses were produced from invitro grown explants of Medicagosativa cv. Yazdi and cv. Hamedani under aseptic condition on MS medium containing NAA, 2,4-D. Then calluses and seedling were transferred to the same medium containing 0,0.2, 0.4, 0.6, 0.8, 1% NaCl and 0, 2, 4, 6, 8, 10% Mannitol as osmotic stress. After 2 weeks acid phosphatse activities were measured and data statistically analyzed. Clearly acid phosphatase activities was increased by salt and drought stress in both cultivars, and the difference between two genotype indicating that the acid phosphatase activity is highly genotype dependent. Key words: Acid phosphatase, Medicago sativa, osmotic, salt, drought, stress. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/02459399191 http://dx.doi.org/10.5897/AJB2003.000-1026 en Copyright © 2003 A. A. Ehsanpour and F. Amini
oai:academicjournals.org:AJB:BA5F3E79195 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Plant retroviruses: structure, evolution and future applications Essam A. Zaki Minireview Retroelements, which replicate by reverse transcription, have been detected in higher plants, higher animals, fungi, insects and bacteria. They have been classified into viral retroelements, eukaryotic chromosomal non-viral retroelements and bacterial chromosomal retroelements. Until recently, retroviruses were thought to be restricted to vertebrates. Plant sequencing projects revealed that plant genomes contain retroviral-like sequences. This review aims to address the structure and evolution of plant retroviruses. In addition, it proposes future applications for these important key components of plant genomes. Key words: Interspecies gene flow, plant genes vectors, plant retroviruses, retroelements, sequence divergence, transgenic plants. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/BA5F3E79195 http://dx.doi.org/10.5897/AJB2003.000-1027 en Copyright © 2003 Essam A. Zaki
oai:academicjournals.org:AJB:37121409201 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Bacillus pumilus BpCRI 6, a promising candidate for cellulase production under conditions of catabolite repression Kotchoni O.S.dagger;, Shonukan O.O. and Gachomo W.E. Full Length Research Paper Cellulose degrading organisms have been used for the conversion of cellulolytic materials into soluble sugars or solvents in several biotechnological and industrial applications. In this report, a mutant of Bacillus pumilus was obtained after chemical mutagenesis and screened for cellulase production. This mutant named BpCRI 6 was selected for its ability to produce cellulase under catabolite repression. Cellulase yield by BpCRI 6 was four times higher than that of the wild type under optimum growth conditions (pH 6.5, 25deg;C and Ca2+ 1mM). In shaking flask cultures, production of cellulase by the wild type was completely repressed in the presence of 25 mM glucose, while BpCRI 6 strain still exhibited a residual cellulase production of 80 and 40% at 25 mM and 40 mM of glucose concentrations respectively. The mutant strain is stable and grows rapidly in liquid and solid media. Under conditions of catabolite repression (40 mM of glucose), the production of cellulase by this mutant is particularly significant when compared to Trichoderma reesei a well-known cellulase producer, which is under control of end-product inhibition. This is the first report of a successful catabolite repression insensitivity of cellulase production by a mutant of B. pumilus. Key words: Cellulase, Bacillus pumilus, BpCRI 6, Catabolite repression. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/37121409201 http://dx.doi.org/10.5897/AJB2003.000-1028 en Copyright © 2003 Kotchoni O.S.dagger;, Shonukan O.O. and Gachomo W.E.
oai:academicjournals.org:AJB:F430A379205 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Production of poly-b-hydroxybutyrate (PHB) and differentiation of putative Bacillus mutant strains by SDS-PAGE of total cell protein Hikmet Katırcıoğlu, Belma Aslım, Zehra Nur Yuuml;ksekdaeth;, Nazime Mercan, Yavuz Beyatlı Full Length Research Paper In this study, the putative mutant strains of Bacillus megaterium Y6, B. subtilis K8, B. sphaericus X3 and B. firmus G2 were studied for their poly-b-hydroxybutyrate (PHB) production capacities. Mutations were induced by using UV light, acriflavin and 5-bromourasil. Total cell proteins were extracted from 59 strains and compared using SDS-PAGE. For each strain, percentage yield of PHB according to cell dry weight was determined in a range of 1.46-63.45%. PHB production of 8 mutant strains were found to increase in comparison with parental strains. However, no increase in PHB production of mutant strains of B. sphaericus X3 was found. It was also determined that the protein profiles of the mutant strains with high PHB yield generally differed from the protein profiles of parental strains. Key words: Bacillus, poly-b-hydroxybutyrate, PHB, total cell protein. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/F430A379205 http://dx.doi.org/10.5897/AJB2003.000-1029 en Copyright © 2003 Hikmet Katırcıoğlu, Belma Aslım, Zehra Nur Yuuml;ksekdaeth;, Nazime Mercan, Yavuz Beyatlı
oai:academicjournals.org:AJB:A00C8C89211 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Cellulase Production by Aspergillus flavus Linn Isolate NSPR 101 fermented in sawdust, bagasse and corncob Ojumu Tunde Victor, Solomon Bamidele Ogbe, Betiku Eriola, Layokun Stephen Kolawole And Amigun Bamikole Full Length Research Paper Bagasse, corncob and sawdust were used as lignocellulosic substrates for the production of cellulase enzyme using Aspergillus flavus after ballmilling and pretreatment with caustic soda. From the fermentation studies, sawdust gave the best result with an enzyme activity value of 0.0743IU/ml while bagasse and corncob gave 0.0573IU/ml and 0.0502IU/ml respectively. The three lignocellulosics gave their maximum enzyme activities at about the twelfth hour of cultivation, suggesting that the 12th hour is the optimum time when the enzyme may be harvested. Key words: Aspergillus flavus, cellulase activity, lignocellulosics. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/A00C8C89211 http://dx.doi.org/10.5897/AJB2003.000-1030 en Copyright © 2003 Ojumu Tunde Victor, Solomon Bamidele Ogbe, Betiku Eriola, Layokun Stephen Kolawole And Amigun Bamikole
oai:academicjournals.org:AJB:E2E33759213 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Detection of DNA alteration in abnormal phenotype of broiler chicken male by random amplified polymorphic DNA (RAPD) Bahy Ahmed Ali Full Length Research Paper RAPD technique was used in this study to detect DNA band variations between both normal and abnormal male of broiler chicken based on RAPD marker. DNA polymorphisms between normal and mutant birds were detected using fifteen oligonucleiotide primers. Using these primers, DNA band loss ranged from 25 to 75%. Data demonstrated that RAPD marker could detect DNA alterations. Keywords: DNA alteration, RAPD, abnormal phenotype, male, broiler chicken. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/E2E33759213 http://dx.doi.org/10.5897/AJB2003.000-1031 en Copyright © 2003 Bahy Ahmed Ali
oai:academicjournals.org:AJB:8813EF19218 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Amplification of 1-amino-cyclopropane-1-carboxylic (ACC) deaminase from plant growth promoting rhizobacteria in Striga-infested soil Olubukola O. Babalola, Ellie O. Osir , Abiodun I. Sanni, George D. Odhiambo, and Wallace D. Bulimo, Full Length Research Paper Experiments were conducted in pots to determine the growth effect of different rhizobacteria on maize under Striga hermonthica infestation. Three bacteria were selected based on their plant growth promoting effects. Whole bacterial cells of the rhizobacteria were used to amplify 1-amino-cyclopropane-1-carboxylic acid (ACC) deaminase gene by polymerase chain reaction (PCR). Each bacterial inoculation increased agronomic characteristics of maize although not always to a statistically significant extent. The extent of growth enhancement differs between the isolates.Enterobacter sakazakii 8MR5 had the ability to stimulate plant growth, however in the PCR study, ACC deaminase was not amplified from this isolate, indicating that not all plant growth-promoting rhizobacteria contain the enzyme ACC deaminase. In contrast, an ACC deaminase specific product was amplified from Pseudomonas sp. 4MKS8 and Klebsiella oxytoca 10MKR7. This is the first report of ACC deaminase in K. oxytoca. Key words: 1-amino-cyclopropane-1-carboxylic acid, ACC deaminase, PCR, rhizobacteria, Striga hermonthica. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/8813EF19218 http://dx.doi.org/10.5897/AJB2003.000-1032 en Copyright © 2003 Olubukola O. Babalola, Ellie O. Osir , Abiodun I. Sanni, George D. Odhiambo, and Wallace D. Bulimo,
oai:academicjournals.org:AJB:602FA2E9223 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
In-vitro inhibition of growth of some seedling blight inducing pathogens by compost-inhabiting microbes S. Muhammad and N. A. Amusa Full Length Research Paper Compost-inhabiting bacteria were studied for their effect on seedling blight inducing pathogens. Aspergillus niger, Trichoderma harzianum, Bacillus cereus and Bacillus subtilis were the microbes found associated with cow dung, sawdust and rice husk composted soils. Sclerotium rolfsii, Fusarium oxysporum, Pythium aphanidermatum and Macrophomina phaseolina were isolated from blighted seedlings of Cowpea, while S. rolfsii, P. aphanidermatum, Helminthosporium maydis and Rhizoctonia solani were isolated from blighted maize seedlings. When these compost-inhabiting microbes were paired with the seedling blight inducing pathogens, T. harzianum grew on the mycelia of all the test fungal pathogens. B. cereus reduced the mycelia growth of Sclerotium rolfsii, F. oxysporum, P. aphanidermatum, H. maydis and R. solani, with inhibitory zones ranging from 35.5% to 53.3%. B. subtilis in culture also inhibited the mycelia growth of all tested pathogenic fungi with inhibitory zones of between 40.0% to 57.8%. The inhibitory activities of the compost-inhabiting microbes might partly be responsible for the efficacy of compost in reducing seedling blight diseases of crops. Key words: seedling blight, growth inhibition, sawdust, cow dung, rice husk, compost soil. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/602FA2E9223 http://dx.doi.org/10.5897/AJB2003.000-1033 en Copyright © 2003 S. Muhammad and N. A. Amusa
oai:academicjournals.org:AJB:D0AB0839227 2003-06-30T00:00:00Z AcademicJournals AJB AJB:2003
Isolation, characterization, and phylogenetic analysis of copia-like retrotransposons in the Egyptian cotton Gossypium barbadense and its progenitors Abdel Ghany A. Abdel Ghany and Essam A. Zaki Full Length Research Paper We have used the polymerase chain reaction to analyze copia-like retrotransposons in the Egyptian cotton and its progenitors. All three cotton species studied contain reverse transcriptase fragments from copia-like retrotransposons. Sequence analysis of these reverse transcriptase fragments reveals that each is different from the others, with predicted amino acid diversities between 9 and 94%. The detection of stop codons and insertions/deletions in the derived amino acid sequences of the Gossypium RT clones, suggests that these clones represent defective retrotransposons. The presence of these sequences in G. barbadense progenitors, however, suggests the presence of active retrotransposons capable of producing new functional copies at an appropriate rate to compensate for the mutational loss of old ones. Phylogenetic analysis provided strong bootstrap support for a monophyletic origin of plant copia-like retrotransposons, yet showed high diversity within all species. Our results suggest that both vertical transmission of copia-like retrotransposons within G. barbadense lineages, and horizontal transmission between G. barbadense and its progenitors have played major roles in the evolution of copia-like retrotransposons in Gossypium. Keywords: Genome structure, Gossypium, repetitive DNA, polyploidy, sequence diversity, retrotransposons. Abbreviations; PCR: polymerase chain reaction, RT: reverse transcriptase gene. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/D0AB0839227 http://dx.doi.org/10.5897/AJB2003.000-1034 en Copyright © 2003 Abdel Ghany A. Abdel Ghany and Essam A. Zaki
oai:academicjournals.org:AJB:80A84EC9234 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Serological versus molecular diagnosis N. J. Tonukari Editorial Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/80A84EC9234 http://dx.doi.org/10.5897/AJB2003.000-1035 en Copyright © 2003 N. J. Tonukari
oai:academicjournals.org:AJB:08CE0F29245 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Production of monoclonal and polyclonal antibodies against a Nigerian isolate of banana streak virus Agindotan B.O. , Thottappilly G., Uwaifo A and Winter S Full Length Research Paper Banana streak virus is serologically and genomically heterogenous worldwide and there has been the need to produce antibodies that can detect all known serotypes of this virus. Antibody production requires purified virus, since BSV titre is low in Musa tissues, there was the need for an efficient method of purifying the virus. We are reporting the first production of two monoclonal antibodies, BSV 3F9/1 and BSV 3D4/2, against an isolate of BSV. Culture fluids of BSV 3F9/1 and BSV 3D4/2 had antibody titres of 1:204,000 and 1:6400, by ELISA, respectively. The two monoclonal antibodies detected all isolates of BSV that were detected by the homologous mouse polyclonal antibodies. Caesium gradient centrifugation reduced yield of BSV during purification. We described a method of purification, which excluded the caesium gradient step and yet increased BSV yield by about 15-fold. The virus preparation obtained by this new method was used to produce BSV-specific mouse and rabbit polyclonal antibodies. These BSV monoclonal antibodies together with the polyclonal antibodies were used for the detection of BSV. Key words: Banana streak virus, monoclonal antibodies, polyclonal antibodies, Musa, TAS-ELISA, polysynthetic antibodies, antigen-coated dot ELISA. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/08CE0F29245 http://dx.doi.org/10.5897/AJB2003.000-1036 en Copyright © 2003 Agindotan B.O. , Thottappilly G., Uwaifo A and Winter S
oai:academicjournals.org:AJB:911917B9252 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Influence of cultural conditions on the production of bacteriocin by Lactobacillus brevis OG1 S.T. Ogunbanwo, A.I. Sanni, and A. A. Onilude Full Length Research Paper Bacteriocin produced by Lactobacillus brevis OG1 has large spectrum of inhibition against pathogenic, food spoilage microorganisms and various Lactic acid bacteria employed as test strains. The bacteriocin inhibited E coli NCTC 10418 andEnterococcus faecalis, but did not inhibit Candida albicans ATCC 10231 andKlebsiella sp. UCH 15. The antibacterial activity appeared to be pronounced between early logarithmic and early stationary phase. Supplementation and/or replacement of nutrients demonstrated that larger quantities of bacteriocin could be produced by addition of yeast extracts (3.0%), NaCl (1.0-2.0%), glucose (1.0 %) and Tween 80 (0.5%), while addition of tri-ammonium citrate, sodium acetate, magnesium sulphate, manganese sulphate and potassium phosphate had no effect on production. Maximal activity in composed medium was achieved at initial pH of 5.5, and incubation period of 48h at 30-370C. Key words: Bacteriocin, growth media, Lactobacillus brevis OG1, indicator organisms, antagonistic activity. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/911917B9252 http://dx.doi.org/10.5897/AJB2003.000-1037 en Copyright © 2003 S.T. Ogunbanwo, A.I. Sanni, and A. A. Onilude
oai:academicjournals.org:AJB:77F5F089257 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Analysis of AVR4 promoter by sequential response-element deletion Olukosi, YA and Iwalokun, BA Full Length Research Paper Several reports have associated the variability in physico-chemical properties of avidin protein to dynamism inherent in the consensus regulatory networks within the promoter region of avidin genes. An Avr4 promoter region ligated to chloramphenicol acetyltransferase plasmid vector (pBLCAT2) to produce recombinant plasmid Avr4pBLCAT2 was sequentially deleted to produce five distinct mutants: Avr4pBLCAT2907-176, Avr4pBLCAT2809-176, Avr4pBLCAT2789-176,Avr4pBLCAT2429-176 and Avr4pBLCAT2302-176. The transformants elicited different chloramphenicol acetyl transferase (CAT) activities. Key words: Avidin, AVR4 promoter, chloramphenicol acetyl transferase. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/77F5F089257 http://dx.doi.org/10.5897/AJB2003.000-1038 en Copyright © 2003 Olukosi, YA and Iwalokun, BA
oai:academicjournals.org:AJB:F26A62D9264 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Efficacy of IgG, Fab, and F(ab')2 fragments of horse antivenom in the treatment of local symptoms after Cerastes cerastes (Egyptian snake) bite Salwa S. Abdel Latif, Soheir Wanas, George Abdel Malak and Madiha H. Helmy Full Length Research Paper The ability of horse antivenoms, consisting of immunoglobulin G (IgG) and its fragmentsF(ab#39;)2 and Fab were comparatively studied in mice to neutralize several effects ofCerastes cerastes venom. The three antivenoms were produced from the same batch of hyperimmune horse plasma. Neutralization was only partial when antivenins were administered intravenously at various time intervals after envenomation. No significant differences were observed among IgG, Fab, and F(ab#39;)2 antivenoms concerning neutralization of hemorrhagic effects. Fab fragments were slightly more effective in neutralizing edema while IgG and F(ab#39;)2 antivenoms were better in neutralizing myonecrosis in experiments involving independent injection of venom and antivenom.Thus these results disagree with the theory that quot;Fab quot; fragments are more effective than whole IgG and F(ab#39;)2 in the neutralization of local symptoms accompanying C. Cerastes venom. Key words: Cerastes cerastes, Egyptian snake, IgG, F(ab#39;)2, Fab. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/F26A62D9264 http://dx.doi.org/10.5897/AJB2003.000-1039 en Copyright © 2003 Salwa S. Abdel Latif, Soheir Wanas, George Abdel Malak and Madiha H. Helmy
oai:academicjournals.org:AJB:62267309268 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Genetics similarity among four breeds of sheep in Egypt detected by random amplified polymorphic DNA markers Bahy Ahmed Ali Full Length Research Paper A genetic analysis using RAPD markers was performed for studying variation in four breeds of sheep (Baladi, Barki, Rahmani and Saffolk). Nineteen random primers were used to amplify DNA fragments in these breeds. RAPD patterns with a level of polymorphism were detected between breeds. Results showed closer proximity of Barki to Rahmani and Baladi (95.7 and 91.3%), respectively. Keywords: Sheep, breeds, RAPD, genetic similarity. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/62267309268 http://dx.doi.org/10.5897/AJB2003.000-1040 en Copyright © 2003 Bahy Ahmed Ali
oai:academicjournals.org:AJB:FBF343E9273 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Nodulation and nitrogen fixation of field grown common bean (Phaseolus vulgaris) as influenced by fungicide seed treatment Ndeye Fatou Diaw GUENE, Adama DIOUF and Mamadou GUEYE Full Length Research Paper A field experiment was conducted at Bel Air station, in Dakar using 15N isotope dilution technique and the non nodulating soybean (Glycine max) variety m129 as reference plant to test the compatibility of Dichlorofenthion-thiram (DCT) fungicide to the inoculation of common bean (Phaseolus vulgaris) Paulista variety with both Rhizobium etli ISRA 353 and R. tropici strain ISRA 554. Nodulation was not induced with R. etliISRA 353 and nitrogen fixation did not occur. With R. tropici ISRA 554, a decrease in nodulation was observed, but nitrogen fixation was not significantly different compared to that of the non DCT-treated common bean. Key words: Common bean, fungicides, isotope dilution, 15N, nitrogen fixation, nodulation, Phaseolus vulgaris, Rhizobium. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/FBF343E9273 http://dx.doi.org/10.5897/AJB2003.000-1041 en Copyright © 2003 Ndeye Fatou Diaw GUENE, Adama DIOUF and Mamadou GUEYE
oai:academicjournals.org:AJB:B96C4E19280 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Inheritance of resistance to head bug (Eurystylus oldi) in grain sorghum (Sorghum bicolor) S. E. Aladele and I. E. Ezeaku Full Length Research Paper The inheritance of resistance to head bug (Eurystylus oldi) was studied in ten populations of sorghum derived from crossing three susceptible sorghum elite varieties (ICSV 111, ICSV 112 and ICSV 400), and two resistant sorghum varieties (Malisor 84-7 and KSV 4). Parental lines, F1 and F2 populations were sown on a Randomized Complete Block Design in two replications. Artificial infestation of head bugs on sorghum was employed in carrying out the experiment. Samples of 5 panicles each from every artificially infested plot were observed. Resistance to head bug in sorghum seems to be controlled by a single pair of recessive genes in Malisor 84-7 x ICSV 400 and Malisor 84-7 x ICSV 111. The cross, KSV 4 x ICSV 112 appeared to be controlled by double recessive pair of genes. Head bug population affects quality of grains rather than the yield produced. There is a negative correlation (-0.095) between head bug population and the germination percentage of the grain. Positive relationship exists between glume size and head bug population, which suggests that longer glumes harbour more head bug. Key words: Head bug (Eurystylus oldi), Infestation, Anthesis, Resistance, Susceptible, Inheritance. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/B96C4E19280 http://dx.doi.org/10.5897/AJB2003.000-1042 en Copyright © 2003 S. E. Aladele and I. E. Ezeaku
oai:academicjournals.org:AJB:B74AB939286 2003-07-31T00:00:00Z AcademicJournals AJB AJB:2003
Comparison of multi-locus enzyme and protein gel electrophoresis in the discrimination of five Fusarium species isolated from Egyptian cottons Ibrahim N. Aly, Mohmed A. Abdel-Sattar, Kamel A. Abd-Elsalam, Mohmed S. Khalil and Joseph A. Verreet Full Length Research Paper Electrophoretic studies of multilocus-enzymes (MLEE) and whole-cell protein (SDS-PAGE) were carried out in order to evaluate the parity between different methods for the characterization of five Fusarium species recovered from cotton-growing areas in Egypt by numerical taxonomy methods. The obtained data revealed that SDS-PAGE and esterase isozymes are more efficient in grouping isolates in their respective species while peroxidase and malate dehydrogenase isozyme has much limited resolution in organizing all isolates in their respective species-specific clusters. A low correlations was detected between geographical origin of isolates and genetic diversity. Results indicate that the estimated inter-specific variation may be more pronounced with protein markers than with isoyzmes when the two approaches are applied to the same populations. The level of genetic variability detected within and between Fusarium spp. accessions with protein and esterase isoyzmes analysis suggests that it is a reliable, efficient, and effective marker technology for determining genetic relationships in Fusarium genus. Key words: Cotton, Fusarium, Isozymes, polyacrylamide gel electrophoresis. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/B74AB939286 http://dx.doi.org/10.5897/AJB2003.000-1043 en Copyright © 2003 Ibrahim N. Aly, Mohmed A. Abdel-Sattar, Kamel A. Abd-Elsalam, Mohmed S. Khalil and Joseph A. Verreet
oai:academicjournals.org:AJB:D5BD9879295 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Stable gene transformation in cowpea (Vigna unguiculata L. walp.) using particle gun method J. Ikea, I. Ingelbrecht, A. Uwaifo and G. Thottappilly,lambda; Full Length Research Paper We investigated the possibility of transforming and obtaining transgenic cowpea (Vigna unguiculata L Walp) plants using the particle bombardment process. Meristematic explants that could give rise to whole fertile plants were used in transformation experiments with reporter and selectable marker genes driven by a 35S CaMV promoter. Conditions for optimal delivery of DNA to explants were established based on transient gus expression assays two days after bombardment. The size of microcarriers, microflight distance and helium pressure significantly affected transient expression of reporter genes. A total of 1692 explants were bombarded with DNA-coated particles and placed on 3 mg/l bialaphos selective medium. Only 12 regenerated shoots produced seeds eventually, and all were Gus negative even though 7 gave positive PCR signals with the bar primer. Eight out of 1400 seeds from To plants were GUS positive. DNA from eight of the GUS positive seedlings were amplified with both the gus and bar primers in PCR analysis but only two gave a positive Southern signal. Only two of the 3557 T2 seedlings obtained were GUS positive. However, 3 seedlings survived Basta spray. The two GUS positive and 3 Basta surviving seedlings gave positive Southern hybridisation signals. Twelve T3 seedlings from these were GUS positive and also gave positive Southern hybridisation signals. The positive reaction of T1, T2 and T3 seedlings under Southern analysis confirms the stable integration of introduced genes and the transfer of such genes to progenies. However, the level of expression of introduced genes in cowpea cells is very low and this accounted for the high mortality rate of progenies under Basta spray. Key words: Transformation, particle bombardment, gus assay, transient expression, reporter gene, basta, bar gene. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/D5BD9879295 http://dx.doi.org/10.5897/AJB2003.000-1044 en Copyright © 2003 J. Ikea, I. Ingelbrecht, A. Uwaifo and G. Thottappilly,lambda;
oai:academicjournals.org:AJB:1BF8AAB9301 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Characterization of bacteriocin produced by Lactobacillus plantarum F1 and Lactobacillus brevis OG1 S.T. Ogunbanwo, A.I. Sanni, and A. A. Onilude Full Length Research Paper Lactobacillus plantarum F1 and L. brevis OG1 isolated from Nigerian fermented food products, produced bacteriocins that had broad spectrum of inhibition against both pathogenic, food spoilage organisms and various lactic acid bacteria. The test organisms exhibited activities of 6400 and 3200 AU/ml respectively against Escherichia coliNCTC10418 and Enterococcus faecalis EF1, but did not inhibit Candida albicansATCC10231 and Klebsiella sp. UCH15. Comparison of the antimicrobial spectra and characterization of the two bacteriocins were not identical. Bacteriocin produced by L. brevis OG1 was the most heat stable at 121oC for 60 min, while that of L. plantarumF1 was stable at 121oC for 10 min. The bacteriocins produced by the test isolates maintained full stability after storage for 60 days at ndash; 200C; partial stability after storage for 120 days at 40C; while activity was not detected after storage for 80 to 120 days at 370C. Bacteriocin produced by L. brevis OG1 was stable at pH range of 2.0 to 8.0 while, that of L. plantarum F1 was found to be stable at pH 2.0 to 6.0. Their active principle was proteinaceous in nature since the bacteriocins were inactivated by proteolytic enzymes, but not by other nonndash;proteolytic enzymes. mitomycin C and uv light did not affect the activity of the bacteriocins, while chloroform extraction completely destroyed their activity. Exposure to surfactant resulted in an increase in the bacteriocin titre, except Nonidet P-40, which led to total loss of bacteriocin activity. The bacteriocins were able to pass through cellulose membranes with 100,000 KDa and 1,000,000 KDa but could not pass through one with a 10,000 KDa and 1,000 KDa molecular weight cut off. The paper concluded that the ability of bacteriocins produced by the test isolates in inhibiting a wide-range of bacteria, is of potential interest for food safety and may have future applications as food preservative. Key words: Bacteriocins, lactic acid bacteria, indicator organisms, fermented foods, antagonistic activity. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/1BF8AAB9301 http://dx.doi.org/10.5897/AJB2003.000-1045 en Copyright © 2003 S.T. Ogunbanwo, A.I. Sanni, and A. A. Onilude
oai:academicjournals.org:AJB:9CC1A859305 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Protein enrichment of solid waste from cocoyam (Xanthosoma sagittifolium (L.) Schott) cormel processing using Aspergillus oryzae obtained from cormel flour Duru, C. Chidi and Uma, Ngwanma U. Full Length Research Paper Aspergillus oryzae obtained from spoilt cormel flour was subjected to mutation treatments using X-rays, solar radiation and bleach. Following selection and screening of viable colonies on a medium containing Xanthosoma cormel solid process waste as the only carbon source, A. oryzae A7 which significantly (p pound; 0.05) produced more biomass at a higher growth rate than the wild parent, was chosen for protein enrichment. Protein content of substrate enriched with the mutant fungal strain was higher than that enriched with the wild strain. Addition of (NH4)2SO4, NH4NO3, NH4Cl, and urea to Xanthosoma solid process waste increased the growth rate of mutant, with the highest increase observed with urea. Medium amended with urea also had the highest protein level of 26.23% strain compared to a protein yield of 17.41% obtained in the control with no added nitrogen. The optimal temperature for protein enrichment was found to be 350C. Key words: Aspergillus oryzae, cormel, protein enrichment, waste, Xanthosoma. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/9CC1A859305 http://dx.doi.org/10.5897/AJB2003.000-1046 en Copyright © 2003 Duru, C. Chidi and Uma, Ngwanma U.
oai:academicjournals.org:AJB:C66D4BC9307 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Constructional features of a 15-litre home-made bioreactor for fed-batch fermentations Gueguim Kana, E.B., Oloke, J.K., Lateef, A. And Zebaze Kana, M.G. Full Length Research Paper A 15-litre bench-top multipurpose bioreactor was designed and constructed. The vessel is a glass type with a stainless flat headplate incorporating 9 access ports allowing for a variety of interchangeable probes and actuators. The stirring speed ranges between 0 and 250 rpm, the aeration rate (0-2 l/m), the pH control loop uses HI 1131 probe, two 100 ml bottles of HCl and NaOH solutions and operates a close feedback system. The temperature control module is a close loop using a PT 100 RTD thermocouple and an auxiliary vessel containing a cooling solution. The aeration and feed flow rates are open loops. The system incorporates attributes of a good bioreactor design as discussed by Naraendranathan (1998). Sterility is achieved by autoclaving different units of the system. This machine has been tested on an array of local standard fermentation processes. Key words: Fermentation, bioreactor, control, sensors, actuators. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/C66D4BC9307 http://dx.doi.org/10.5897/AJB2003.000-1047 en Copyright © 2003 Gueguim Kana, E.B., Oloke, J.K., Lateef, A. And Zebaze Kana, M.G.
oai:academicjournals.org:AJB:7FB02F59314 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Comparison of an African herbal formula with commercially available haematinics OKOCHI VI, OKPUZOR J, ALLI LA Full Length Research Paper The haematological changes observed with commercially available haematinics (Fagon 9reg; and Chemironreg;) were compared with those of a local haematinic referred to as African Herbal Formula (AHF). Results showed that AHF produced effects in haemoglobin (Hb) and packed cell volume (PCV) levels, which are reasonably comparable with the reference commercial and chemically defined haematinics. Key words: Haematological changes, haematinics, African Herbal Formula,Trypanosome brucei brucei. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/7FB02F59314 http://dx.doi.org/10.5897/AJB2003.000-1048 en Copyright © 2003 OKOCHI VI, OKPUZOR J, ALLI LA
oai:academicjournals.org:AJB:F41A0929317 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Rhesus negative pregnant women in a traditional birth home in Abeokuta, Nigeria Idowu, O.A., Mafiana, C.F. and Sotiloye, Dapo Short Communication In a survey of 200 pregnant women (mean age 24 years) attending a traditional birth home (TBH) in Abeokuta, Nigeria, 19 (9.5%) were found to be rhesus negative, 8 (42.1%) of which were primigravidae while 11 (57.9%) were multigravidae. 87.5% of the Rhesus negative primigravidae delivered at the TBH without being given the post partum injection of anti-D-gama globulin within 72 h of delivery, thereby having their systems likely sensitized (if baby is rhesus positive) against subsequent pregnancies involving Rhesus positive fetuses. Of the multigravidae involved in this study 27.3% women delivered live babies at the traditional birth home while the remaining 72.7% women were not seen again at the TBH. One woman who has had an induced abortion and was carrying a second pregnancy lost the pregnancy in the course of this study. The knowledge of these women (who were mostly without formal education) on their haematological status is nil. The need to educate the public, especially women patronizing TBH, on the rhesus problem is recommended. Key words: Pregnancy, Rhesus factor, traditional birth home. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/F41A0929317 http://dx.doi.org/10.5897/AJB2003.000-1049 en Copyright © 2003 Idowu, O.A., Mafiana, C.F. and Sotiloye, Dapo
oai:academicjournals.org:AJB:E61598A9323 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Chloroquine-resistant Plasmodium falciparum in Sokoto, North Western Nigeria K. Abdullahi, S. Muhammad, S. B. Manga and I. M. Tunau Short Communication Three patients, 30, 2 and one and a half years, were diagnosed as having falciparummalaria and were placed on chloroquine therapy which failed. They were then placed on quinine therapy that then cleared the parasitaemia. This case report seeks to draw the attention of the presence of possible chloroquine-resistant falciparum malaria in Sokoto, North Western Nigeria. Key words: Chloroquine-resistant malaria, Plasmodium falciparum, haemoglobin level, packed cell volume. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/E61598A9323 http://dx.doi.org/10.5897/AJB2003.000-1050 en Copyright © 2003 K. Abdullahi, S. Muhammad, S. B. Manga and I. M. Tunau
oai:academicjournals.org:AJB:43521399333 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Genetic fingerprinting and phylogenetic diversity of Staphylococcus aureus isolates from Nigeria Onasanya A., Mignouna H.D, and Thottappilly G., Full Length Research Paper Genetic fingerprinting of 18 different isolates of Staphylococcus aureus from Nigeria using random amplified polymorphic DNA (RAPD) was carried out. Ten out of 100 Operon primers showed polymorphism among the isolates tested generating 88 bands, 51 of which were polymorphic with sizes ranging between 200 and 3,000 bp. All the isolates were classified completely into two major groups (Sa-1 and Sa-2) with twelve different subgroups. Sa-1 group originated from human while isolates from plant and animal origins formed the Sa-2 group. The twelve different subgroups suggestadaptation of S. aureus in the different host cells. This indicates possible relationship between host origin and genetic variation among S. aureus isolates. The DNA fingerprint defined for each race of S. aureus could be useful in epidemiological studies, medical diagnosis and the identification of new strains and their origins. Keywords: Staphylococcus aureus, foodborne-acquired infections, genetic fingerprinting; phylogenetic diversity, RAPD, polymorphism. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/43521399333 http://dx.doi.org/10.5897/AJB2003.000-1051 en Copyright © 2003 Onasanya A., Mignouna H.D, and Thottappilly G.,
oai:academicjournals.org:AJB:7525BFA9338 2003-08-31T00:00:00Z AcademicJournals AJB AJB:2003
Isolation of total DNA from bacteria and yeast Marco Ligozzi and Roberta Fontana Short Communication Many procedures in molecular biology require the isolation of high quality genomic DNA. This study investigated a new method to extract DNA from Gram-negative, Gram-positive bacteria, Mycobacteria and yeasts. Guanidine thioisocyanate present in DNAzol is capable of binding DNA to silica particle column. Subsequently the silica with adsorbed DNA is washed to remove impurities and the clean DNA eluted in appropriate buffer. Results indicated that the new extraction method is simple and reproducible. This isolation technique is faster and easier to perform than the other conventional extraction methods. Finally the recovered DNA is of high quality and suitable for downstream applications. Key words: DNAzol, DNA isolation, bacteria, yeast. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/7525BFA9338 http://dx.doi.org/10.5897/AJB2003.000-1052 en Copyright © 2003 Marco Ligozzi and Roberta Fontana
oai:academicjournals.org:AJB:6AB313C9881 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Mycotoxins in food in West Africa: current situation and possibilities of controlling it S.A. Bankole and A. Adebanjo Review This review presents the different mycotoxins (aflatoxins, fumonisins and ochratoxin A) produced in agricultural crops in the West African sub-region. The acute and chronic toxic effects of the various mycotoxins are presented. Maize and groundnuts have been found to be excellent substrate for aflatoxin contamination, while fumonisins are widely distributed in maize. Other food products for which mycotoxin contamination has been reported in the sub-region include dried yam chips, tiger nut, melon seeds and stored herbal plants. Mycotoxin contamination is favoured by stress factors during plant growth, late harvesting of crops, high ambient humidity preventing thorough drying, unscientific storage practices and lack of awareness. Control measures include education of the populace on the danger of mycotoxin contaminated diet, early harvesting, rapid drying, sorting, sanitation, use of improved storage structures, smoking, insect control, the use of botanicals and synthetic chemicals as storage protectants, fumigation, biological control, the use of resistant varieties and detoxification of mycotoxin contaminated grains. Key words: Mycotoxins, aflatoxins, food, fumonisins, ochratoxin A, surveillance, toxicology, prevention, control, West Africa. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/6AB313C9881 http://dx.doi.org/10.5897/AJB2003.000-1053 en Copyright © 2003 S.A. Bankole and A. Adebanjo
oai:academicjournals.org:AJB:7BCF3479885 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Mevastatin-induced inhibition of cell growth in avocado suspension cultures and reversal by isoprenoid compounds Dudley I. Mitchell and A. Keith Cowan Full Length Research Paper Cell suspension cultures were established using soft, friable callus derived from nucellar tissue of lsquo;Hassrsquo; avocado (Persea americana Mill.) seed from fruit harvested 190 days after full bloom. Cell cultures were maintained in liquid medium supplemented with naphthalene acetic acid (NAA), isopentenyl adenine (iP) and sucrose and sub-cultured at 14 day intervals. Growth was typically sigmoidal with a lag phase of 7 days followed by an exponential phase of approximately 14 days. Mevastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR, EC was used to probe the contribution of metabolites of the isoprenoid pathway for avocado cell growth. Treatment with mevastatin inhibited cell growth and caused loss of cell viability. Inhibition of cell growth was transient and at all concentrations of mevastatin tested, recovery was evident within 17 days. The arrest of cell growth by 1 and 40 mu;mol/L mevastatin was negated when this inhibitor of HMGR was supplied in the presence of either mevalonolactone (MVL) or farnesyl diphosphate (FDP). By comparison, co-treatment of cells supplied 1 mu;mol/L mevastatin with stigmasterol showed little or no response whereas at 40 mu;mol/L mevastatin, stigmasterol induced partial recovery of cell growth. The results indicate a requirement for mevalonic acid (MVA) and cytosolic isoprenoid biosynthesis, in particular FDP, for avocado cell growth and support the hypothesis that appearance of the small-fruit phenotype in lsquo;Hassrsquo; is inextricably linked to activity of HMGR. Key words: Avocado, cell suspensions, farnesyl diphosphate, HMGR, mevalonic acid,Persea americana. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/7BCF3479885 http://dx.doi.org/10.5897/AJB2003.000-1054 en Copyright © 2003 Dudley I. Mitchell and A. Keith Cowan
oai:academicjournals.org:AJB:774B1E69899 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Phylogenetic and molecular evolutionary analyses of gypsy group retrotransposon families in the Egyptian cotton Gossypium barbadense Abdel Ghany A. Abdel Ghany and Essam A. Zaki Full Length Research Paper Gypsy group retrotransposons in the Egyptian cotton, Gossypium barbadense, was examined by phylogenetic and molecular evolutionary analyses. DNA sequences ofgypsy group retrotransposons in two G. barbadense cultivars revealed that these sequences are heterogeneous and represent two distinct families. Sequence variation between these families seems to preserve coding information of the reverse transcriptase domain. The high ratio of synonymous to nonsynonymous changes indicates that the reverse transcriptase domain of these families is evolving under purifying selection. Our phylogenetic analysis revealed that the closest relatives of cotton retroelements are found in other plants gypsy group retrotransposons. Cotton retroelements-encoded transcripts were detected in their related respective young seedlings using RNA slot-blot hybridization, suggesting their transcriptional activity. The wide distribution of gypsygroup retrotransposons and the detection of their encoded transcripts illustrate their active role in the Gossypium genome. Key words: Evolution, Gossypium, gypsy, retrotransposons, reverse transcriptase, substitution rates, transcription. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/774B1E69899 http://dx.doi.org/10.5897/AJB2003.000-1055 en Copyright © 2003 Abdel Ghany A. Abdel Ghany and Essam A. Zaki
oai:academicjournals.org:AJB:94AC2999925 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Effects of sulphuric acid and hot water treatments on seed germination of tamarind (Tamarindus indica L) S. Muhammad and N. A. Amusa Full Length Research Paper A study was carried out to investigate the effects of sulphuric acid and hot water treatments on the germination of Tamarind (Tamarindus indica L). Seeds were placed on moistened filter papers in 28 cm diameter Petri dishes under laboratory condition for germination. 330 seeds of T. indica (10 seeds per Petri dish) with three replicates each were used. The highest germination was recorded in seeds treated with 50 per cent sulphuric acid concentration with 60 min soaking period. Germination was observed to be enhanced by increase in the sulphuric acid concentration, water temperature, and soaking period in all the trials, except with absolute sulphuric acid where poor response was observed. Results of this study may serve as useful information in the production and improvement of the tree species, as knowledge on seed germination requirements is a critical factor in seedlings production. Key words: Tamarind, Tamarindus indica, sulphuric acid, hot water, germination. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/94AC2999925 http://dx.doi.org/10.5897/AJB2003.000-1056 en Copyright © 2003 S. Muhammad and N. A. Amusa
oai:academicjournals.org:AJB:F42047A9952 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Heavy metals concentrations and burden in the bivalves (Anadara (Senilia) senilis, Crassostrea tulipa and Perna perna) from lagoons in Ghana: Model to describe mechanism of accumulation/excretion Fred A. Otchere Full Length Research Paper Seasonal sampling of the bivalves: Anadara (Senilia) senilis (n = 260), Crassostrea tulipa (n = 220), from two lsquo;openrsquo; lagoons (Benya and Ningo) and a lsquo;closedrsquo; lagoon (Sakumo), and Perna perna (n = 170), from rocky shores adjacent to Benya and Sakumo, were analyzed for their total Cu, Zn, Fe, Mn, Cd and Hg concentrations and total body burden (that is concentration multiply by total flesh weight). Median concentrations for cockles were: 5, 38, 710, 10, 0.22 and 0.20 g/g dw respectively. Cd and Hg levels in dry season samples were higher than those in wet season. While Zn and Fe dry season levels were lower than wet season with no variation in Cu and Mn. Median total body burden in cockles were: 3.3, 30.5, 370, 5.2, 0.28 and 0.13 g respectively. Geographical variations observed were mostly due to size distribution rather than the ecological differences between stations. Log-transformed regression relationships between body burden and size were used to compare the species. Relationship between condition index, body burden and concentration were used to develop a model to describe mechanism of accumulation/excretion. Key words: Heavy metals, bivalves, marine, lagoons, seasonal variation, accumulation, Ghana. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/F42047A9952 http://dx.doi.org/10.5897/AJB2003.000-1057 en Copyright © 2003 Fred A. Otchere
oai:academicjournals.org:AJB:3DC485710138 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Petroleum degrading potentials of single and mixed microbial cultures isolated from rivers and refinery effluent in Nigeria P.O. Okerentugba and O.U. Ezeronye Full Length Research Paper The ability of three bacterial isolates (Bacillus spp, Micrococcus spp and Proteus spp.) and some fungal species (Penicillin spp., Aspergillus spp. and Rhizopus spp.) isolated from two rivers and refinery effluent to degrade two Nigerian Crude oils was studied. The results showed changes in pH, optical density and total viable count for the bacterial isolates after a 17-day period. There was an increase in biomass for the fungal isolates after a 35-day period. It was observed that these organisms were able to utilize and degrade the crude oil constituents, with bacterial isolates showing increase in cell number and optical density as pH decreases. Single cultures were observed to be better crude oil degraders than the mixed cultures (bacteria or fungi). It was also observed that oil degraders could be isolated from a non-oil polluted environment, although those from oil-polluted environments have higher degradation potentials. Key words: Petroleum, refinery, biodegradation, plasmids, effluent. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/3DC485710138 http://dx.doi.org/10.5897/AJB2003.000-1058 en Copyright © 2003 P.O. Okerentugba and O.U. Ezeronye
oai:academicjournals.org:AJB:A59E3A010142 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Drilling fluid base oil biodegradation potential of a soil Staphylococcus species C. O. Nweke and G. C. Okpokwasili Full Length Research Paper Staphylococcus sp. isolated from oil-contaminated soil was grown in 1% drilling fluid base oil, HDF- 2000, as a sole source of carbon and energy. The organism has strong affinity for the substrate, growing at the rate of 0.16 h-1. It uses adherence and emulsification as mechanisms for oil uptake. In a nutrient-rich marine broth, base oil (up to 2.0% v/v) and glucose (up to 1.6% w/v) have no significant effect on the growth rates. This showed that the Staphylococcus sp. is a strong primary utilizer of the base oil and has potential for application in bioremediation processes involving oil-based drilling fluids. Key words: Drilling fluid base oil, Staphylococcus sp., biodegradation. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/A59E3A010142 http://dx.doi.org/10.5897/AJB2003.000-1059 en Copyright © 2003 C. O. Nweke and G. C. Okpokwasili
oai:academicjournals.org:AJB:B35079F10148 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Enzyme activity of a Phanerochaete chrysosporium cellobiohydrolase (CBHI.1) expressed as a heterologous protein from Escherichia coli Howard R.L., Masoko P. and Abotsi E. Full Length Research Paper The aim of this study was to produce a secreted, heterologously expressedPhanerochaete chrysosporium cellobiohydrolase (CBHI.1) protein that required no in vitro chemical refolding and to investigate the cellulolytic activity of the clone expressing the glutathione S-transferase (GST) fused CBHI.1 protein. Plate enzyme activity screening of E. coli cells transformed with pGEXcbhI.1 vector on carboxy-methyl-cellulose (CMC) produced several clones which produced clearing zones on CMC when induced. A randomly selected representative pGEXcbhI.1 clone produced hydrolysis on both Avicel and CMC when induced. Crude protein extracts obtained from the induced pGEXcbhI.1 clone exhibited time dependent enzymatic activity against both CMC and Avicel. Key words: Phanerochaete chrysosporium, cellobiohydrolase, cellulase activity, heterologous expression. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/B35079F10148 http://dx.doi.org/10.5897/AJB2003.000-1060 en Copyright © 2003 Howard R.L., Masoko P. and Abotsi E.
oai:academicjournals.org:AJB:772CC2910152 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Effect of ripening on the composition and the suitability for jam processing of different varieties of mango (Mangifera indica) Germain Kansci, Benoit Bargui Koubala, Israel Mbome Lape Full Length Research Paper As part of an effort to solve the problem of post harvest losses of fruits, physicochemical characteristics of four mango varieties (Palmer, Ameacute;lioreacute;e, Mango and Keitt) were determined at two ripening stages. Their suitability for jam processing was also evaluated based on viscosity measurements. The pulps of pre-ripe mangoes were highly acidic (pH: 3.50 ndash; 3.85), rich in starch (4.4 ndash; 11.1 % w/w) as well as in dry matter. They contained less soluble sugars (4.04 ndash; 7.56 g/100 g) and recorded lower viscosity values than those of the ripe mangoes. The pre-ripe Palmer and Ameacute;lioreacute;e mango varieties had high dry matter content, while the Mango and Ameacute;lioreacute;e varieties had higher soluble sugars contents. Due to their higher starch contents, all the jams prepared with pre-ripe mangoes were more viscous than the ripe mango preparations. Ripe Palmer and Ameacute;lioreacute;e varieties were the best for jam processing, based on their viscosity values. These results could help to improve the quality of mango jams. Key words: Mango, proximate analysis, ripening stage, jam processing. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/772CC2910152 http://dx.doi.org/10.5897/AJB2003.000-1061 en Copyright © 2003 Germain Kansci, Benoit Bargui Koubala, Israel Mbome Lape
oai:academicjournals.org:AJB:4E882F510159 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Response of Trypanosoma brucei brucei–induced anaemia to a commercial herbal preparation Patrick O Erah, Canice C Asonye and Augustine O Okhamafe Full Length Research Paper Jubi Formulareg; is a herbal preparation made from three medicinal herbs (Parquetina nigrescens, Sorghum bicolor and Harungana madagascariensis). It has been reported to have been successfully used in the treatment of anaemia in humans. A study was therefore carried out to determine the effect of the preparation on packed cell volume (PCV) and haemoglobin (Hb) concentrations in anaemic rabbits. The PCV and Hb concentrations of healthy rabbits infected with Trypanosoma brucei brucei were monitored for 49 days. T. b. brucei produced a significant reduction in PCV and Hb concentrations in all infected rabbits when compared with the controls (plt;0.05). These hematological parameters were restored to normal levels in the anaemic rabbits by the herbal preparation. The anaemic rabbits not treated with the herbal preparation presented with a progressive decline in their PCV and Hb concentrations and majority of them died before the end of the study. Healthy rabbits that received daily doses of the herbal preparation showed gradual elevation in PCV and Hb concentrations which were maintained within normal range. Jubi Formulareg; can restore the PCV and Hb concentrations in anaemic conditions and is a potential substitute for blood transfusion. However, further studies are needed to investigate the potentials of the herbal preparation in reversing anaemia. Key words: Anaemia, PCV, rabbits, haemoglobin, herbal preparation. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/4E882F510159 http://dx.doi.org/10.5897/AJB2003.000-1063 en Copyright © 2003 Patrick O Erah, Canice C Asonye and Augustine O Okhamafe
oai:academicjournals.org:AJB:129DFB710168 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
The influence of African Herbal Formula on the haematological parameters of trypanosome infected rats Okochi VI, Okpuzor J, Okubena MO, Awoyemi AK Full Length Research Paper A herbal mixture of herbs code named African Herbal Formula (AFH) influenced the state of anaemia in trypanosome infected rats. Observations showed that the formula has an effect on the haemopoietic system manifested by a positive increase in the levels of haemoglobin, packed cell volume and red blood cell while the white blood cell and lymphocyte levels were decreased. AHF also delayed the proliferation of the parasites and improved the level of the characteristic weight loss associated with trypanosomiasis. Key words: African Herbal Formula, trypanosomiasis, anaemia. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/129DFB710168 http://dx.doi.org/10.5897/AJB2003.000-1064 en Copyright © 2003 Okochi VI, Okpuzor J, Okubena MO, Awoyemi AK
oai:academicjournals.org:AJB:D5DE8FC10177 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
In vitro trypanocidal effect of methanolic extract of some Nigerian savannah plants S.E. Atawodi, T. Bulus, S. Ibrahim, D.A. Ameh, A.J. Nok, M. Mamman, M. Galadima Full Length Research Paper Methanol extracts from twenty three plants harvested from the Savannah vegetation belt of Nigeria were analyzed in vitro for trypanocidal activity against Trypanosoma brucei brucei and Trypanosoma congolense at concentrations of 4 mg/ml, 0.4 mg/ml and 0.04 mg/ml. Extracts of Khaya senegalensis, Piliostigma reticulatum, Securidacalongepedunculata and Terminalia avicennoides were strongly trypanocidal to both organisms while extracts of Anchomanes difformis, Cassytha spp, Lannea kerstingii, Parkia clappertioniana, Striga spp, Adansonia digitata and Prosopis africana were trypanocidal to either T. brucei brucei or T. congolense. These findings provide evidence of the effects of some plants in the traditional management of trypanosomiasis. Key words: Savannah, medicinal plants, trypanocidal effects, trypanosomiasis, trypanosome, in vitro model. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/D5DE8FC10177 http://dx.doi.org/10.5897/AJB2003.000-1065 en Copyright © 2003 S.E. Atawodi, T. Bulus, S. Ibrahim, D.A. Ameh, A.J. Nok, M. Mamman, M. Galadima
oai:academicjournals.org:AJB:5DD21BA10181 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Plasmid profile of Escherichia coli 0157:H7 from apparently healthy animals Smith SI, Aboaba OO, Odeigha P, Shodipo K, Adeyeye JA, Ibrahim A, Adebiyi T, Onibokun H and Odunukwe NN Short Communication One hundred samples from healthy animals were screened for the presence of enterohaemorrhagic Escherichia coli 0157: H7 and 17 were positive for EHEC 0157:H7 after confirmation using serology kits. Antibiotic susceptibility patterns showed the isolates to be highly susceptible to the various antibiotics screened with a few showing multiple antibiotic resistance. The plasmid profiles revealed that 8/17 (47%) of the animal isolates harboured detectable plasmids ranging in size from 0.564 kb to gt;23 kb. Key words: Escherichia coli, EHEC, animals, plasmid profile. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/5DD21BA10181 http://dx.doi.org/10.5897/AJB2003.000-1066 en Copyright © 2003 Smith SI, Aboaba OO, Odeigha P, Shodipo K, Adeyeye JA, Ibrahim A, Adebiyi T, Onibokun H and Odunukwe NN
oai:academicjournals.org:AJB:6D517F210189 2003-09-30T00:00:00Z AcademicJournals AJB AJB:2003
Larvaecidal effects of aqueous extracts of Azadirachta indica (neem) on the larvae of Anopheles mosquito ALIERO, B.L. Short Communication The effect of crude aqueous extracts of Azadirachta indica (neem) against the larvae of Anopheles mosquito was investigated. Exposure of the larvae to undiluted extracts of seed oil, leaf and bark for 12 hours led to 100, 98, and 48% mortality, respectively. Dilution of these extracts also resulted in mortality of the larvae. We suggest that the seed oil and leaf extract of neem contain properties that could be developed and used in the control of mosquitoes in the tropics. Key words: Anopheles mosquito, neem, Azadirachta indica. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/6D517F210189 http://dx.doi.org/10.5897/AJB2003.000-1067 en Copyright © 2003 ALIERO, B.L.
oai:academicjournals.org:AJB:BC9B7FF10206 2003-10-31T00:00:00Z AcademicJournals AJB AJB:2003
Genetic transformation of forest trees Diaga Diouf Minireview In this review, the recent progress on genetic transformation of forest trees were discussed. Its described also, different applications of genetic engineering for improving forest trees or understanding the mechanisms governing genes expression in woody plants. Key words: Genetic transformation, transgenic forest trees, gene expression. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/BC9B7FF10206 http://dx.doi.org/10.5897/AJB2003.000-1068 en Copyright © 2003 Diaga Diouf
oai:academicjournals.org:AJB:F5AE98210212 2003-10-31T00:00:00Z AcademicJournals AJB AJB:2003
Phylogenetic diversity and relationships among sorghum accessions using SSRs and RAPDs Agrama H. A., and Tuinstra M. R. Full Length Research Paper Two DNA-based fingerprinting techniques, simple sequence repeats (SSR) and random amplified polymorphic DNA (RAPD) analyses, were applied in sorghum germplasm analysis to compare suitability for quantifying genetic diversity. Twenty-two sorghum genotypes, representing an array of germplasm sources with important agronomic traits, were assayed for polymorphism using 32 RAPD primers and 28 sets of sorghum SSR primers. The results indicated that SSR markers were highly polymorphic with an average of 4.5 alleles per primer. The RAPD primers were less polymorphic with nearly 40% of the fragments being monomorphic. An analysis of genetic diversity among sorghum lines indicated that the genetic distances calculated from SSR data were highly correlated with the distances based on the geographic origin and race classifications. Based on the results of these studies, SSR markers appear to be particularly useful for the estimation of genetic similarity among diverse genotypes of sorghum. Key words: cluster, diversity, polymorphism, RAPD, Sorghum, SSR. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/F5AE98210212 http://dx.doi.org/10.5897/AJB2003.000-1069 en Copyright © 2003 Agrama H. A., and Tuinstra M. R.
oai:academicjournals.org:AJB:93694B310226 2003-10-31T00:00:00Z AcademicJournals AJB AJB:2003
Sequence heterogeneity of the envelope-like domain in the Egyptian cotton Gossypium barbadense Abdel Ghany A. Abdel Ghany and Essam A. Zaki Full Length Research Paper The current study aimed to investigate the evolution of env-like sequences in the Egyptian cotton Gossypium barbadense. DNA sequence determination and analysis ofenv-like sequences revealed that these sequences are heterogeneous in G. barbadense. The observed sequence diversity, however, seems to preserve the coding information. Phylogenetic analysis demonstrated that plant env-like sequences group together, suggesting their monophyletic origin. Gossypium env-like sequences are, however, more closely related to elements present in other plant species. Our result suggests thatenv-like sequences in cotton have evolved under functional constraint and likely to play a role in the life cycle of these elements. Key words: Envelope, Gossypium, gypsy, plant retroviruses, retrotransposons, retroviruses, reverse transcriptase. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/93694B310226 http://dx.doi.org/10.5897/AJB2003.000-1070 en Copyright © 2003 Abdel Ghany A. Abdel Ghany and Essam A. Zaki
oai:academicjournals.org:AJB:13EDC5B10231 2003-10-31T00:00:00Z AcademicJournals AJB AJB:2003
Influence of nitrogen, phosphorus and potassium application on the yield of maize in the savanna zone of Nigeria Kogbe J. O. S. and Adediran J. A. Full Length Research Paper Field trials testing the effects of five rates each of N, P and K application on three hybrid and two open-pollinated maize varieties were conducted in three separate experiments on an Arenic haplustalf (USDA) at Ilora in the derived savanna and Typic paleustalf (USDA) at Mokwa in the southern guinea savanna of Nigeria. The hybrid maize varieties planted were 8516-12, 8321-18 and 8329-15 and were compared with the open-pollinated maize, TZSR-Y and TZSR-W. Nitrogen was applied at rates 0-200 kg ha-1 in the first trial, while P and K were supplied as basal nutrients. In the second trial, P was applied at rates 0- 80 kg P2O5 ha-1 using basal N and K fertilizers. In another trial, K was applied at rates 0-120 kg ha-1 with blanket application of N and P. The hybrid maize gave higher yields and used N and P more efficiently than the open pollinated at both trial locations. The yield of maize was higher in the southern guinea savanna than in the derived savanna. The performance of the hybrid varieties followed in the ascending order of 8516-12, 8321-18 and 8329-15. The optimum rates of N and P for maize grown in the derived savanna were 100 and 40 kg ha-1respectively. In the southern guinea savanna the open pollinated and hybrid varieties responded up to 150 and 200 kg N ha-1 respectively. The 8516-12 showed higher N and P use efficiency than other varieties. Consequently, planting such variety could be advantageous, using minimal dose of fertilizer most especially, where farmers have less access to fertilizer. Key words: Hybrid maize, open pollinated maize, nitrogen use efficiency, phosphorus use efficiency. Academic Journals 2003 TEXT text/html http://www.academicjournals.org/journal/AJB/article-abstract/13EDC5B10231 http://dx.doi.org/10.5897/AJB2003.000-1071 en Copyright © 2003 Kogbe J. O. S. and Adediran J. A.