FUNCTIONAL PROPERTIES OF LACTIC ACID BACTERIA ISOLATED FROM OGI AND FUFU, TWO NIGERIAN FERMENTED FOODS

摘要

Lactobacillus plantamm and Leuconostoc mesenter-oides isolated from fufu (retted cassava) and Lactobacillus brevis and Lactobacillus acidophilus from ogi (fermented cereal gruel) were investigated for their technologically important traits, which include bile salt tolerance, acid resistance, production of antimicrobial compounds and macromolecule-degrading ability, L. plantamm exhibited highest resistance to 3% physiological bile salt with a growth delay of 24 min. All the isolates tolerated acidic conditions with L. plantamm showing the highest level of tolerance and surviving in pH 1.0 for 4 hours. This strain also recorded the highest yield of lactic acid (16.4 g/l), while L. brevis had the lowest yield of 6.3 g/l. All the test organisms produceddiacetyl, with Leuconostoc mesente-riodes recording the highest value (3.66 g/l). Hydrogen peroxide was also produced to a varying degree by all the test isolates, with Leuconostoc mesenteroides producing the highest quantity (0.044 g/l). Bacteriocin produced by the test isolates inhibited Escherichia coli NCTC 10418, Mi-crococcus luteus NCEEB 196, Staphylococcus aureus NCTC 6571, and Listeria monocytogenes 587 CHRL. However, none of the test isolates showed cellulolytic activity on solid cellulose medium, but L. acidophilus and L. plantamm exhibited lipolytic activity, while all the test isolates showed amylolytic activity on solid starch medium.