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Full Length
Research Paper
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Assessment
of antibiotics production potentials in four actinomycetes
isolated from aquatic environments of the Eastern Cape
Province of South Africa
Cwala Z.,
Igbinosa E. O. and Okoh A. I*.
Applied and Environmental Microbiology Research Group (AEMREG),
Department of Bio-chemistry and Microbiology, University of Fort Hare, Alice
5700, Private Bag X1314, South Africa.
*Corresponding author. E-mail:
aokoh@ufh.ac.za.
Accepted 21 January, 2011 |
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Abstract |
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Crude extracts of four actinomycetes species
belonging to
Actinoplane
[NB 034], Streptomyces [TR 007] and
Actinopolyspora [NB 069 and TR 008]
genera were screened for antibacterial
activities against a wide range of bacterial
strains. The extracts showed antibacterial
activities against both Gram-negative and
Gram-positive test bacteria with zones of
inhibition ranging between 2 and 27 mm (NB 034);
9 and 15 mm (TR 007); 8 and13 (NB 069) and 2 and
12 mm (NB 069). The minimum inhibitory
concentration (MIC) of the extracts against the
test bacteria ranged from 0.039 - 5 mg/ml, while
the minimum bactericidal concentrations (MBC)
ranged from 5 to >10 mg/ml. The extracts
exhibited concentration-time dependent killing
of Staphylococcus aureus OKOH2A and
Staphylococcus scuiri OKOH2B with a 0.73log10
and 0.88log10 reduction in
viable counts respectively, while a re-growth
phenomenon was exhibited by Klebsiella
pneumonia ATCC 4352
and Escherichia coli ATCC 25922
at MIC, 2 × MIC and 4 × MIC of
Streptomyces
(TR 007)
Actinopolyspora
(TR 008) extracts. All the active extracts
exhibited bacteriostatic activities.
Key words: Actinoplane, Streptomyces, Actinopolyspora, antibiotic
production.
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