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Functional characteristics
of Lactobacillus plantarum and Lactobacillus
rhamnosus from ikii, a Kenyan traditional fermented
maize porridge
Christine M. Kalui, Julius M. Mathara, Philip M. Kutima*,
C. Kiiyukia and Lawrence E. Wongo
Department
of Food Science and Technology, Jomo Kenyatta University of
Agriculture and Technology, P. O. Box 62000 - 00200,
Nairobi, Kenya.
*Corresponding author. E-mail:
pmkutima@yahoo.com.
Tel.: 254-720-467120.
Accepted 10
August, 2009 |
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Fermented foods have been associated with probiotics:
microorganisms that are useful to the host. The potential
probiotic characteristics of Lactobacillus plantarum
and Lactobacillus rhamnosus strains isolated from
ikii, a traditional fermented maize porridge, were
studied and with regard to acid/bile tolerance,
antimicrobial activity, utilisation of fructooligosaccharide,
production of exopolysaccharides and safety attributes. Out
of 19 strains of L. plantarum and one L. rhamnosus,
18 strains of L. plantarum were able to tolerate pH 2
for a period of 3 h. All the L. plantarum and L.
rhamnosus strains assayed tolerated pH 2.5 for a period
of 3 h, population counts remaining at levels of between 5
to7 log cfu/ml. Following 3 h exposure to pH 2, 18 L.
plantarum strains were able to tolerate and grow to
levels between 5 and 6 log cfu/ml in MRS supplemented with
0.3% bile salts within a period of 24 to 48 h. Sixteen (16)
strains of L. plantarum exposed to pH 2.5, were able
to grow to levels of 5 and 7 log cfu/ml in MRS
broth supplemented with 0.3% bile within a period of 24 to
48 h. The assayed strains showed antimicrobial activity
against E. faecalis, S. aureus and E. coli.
Two (2) strains of L. plantarum were able to utilise
a fructooligosaccharide. All 20 strains were able to produce
exopolysaccharides. None of the assayed strains showed
haemolytic and gelatinase activity. It is therefore possible
that L. plantarum involved in production of ikii
do have potential probiotic attributes.
Key
words:
Probiotics,
Lactobacillus plantarum,
Lactobacillus rhamnosus, acid/bile tolerance,
antimicrobial activity, exoplysaccharides,
fructooligosacharides. |
