ABSTRACT

 Many food-grade bacteria such as Lactic Acid Bacteria (LAB) produce excess of B vitamins such as folate (vitamin B9) and cobalamin (vitamin 812)- This unique property of bacteria offers the possibility to fortify raw dairy food such as Nunu (a fermented diary product) with B vitamins by natural means. This work studied the production potency offolate and cobalamin by lactic acid bacteria isolated from Nunu. Four LAB species were isolated and identified from the sample which include Lactococcus lactis, Streptococcus thermophilus, Pediococcus pentosaceus and Lactobacillus plantarum based on morphological, biochemical and physiological characteristics. The production potency of folate and cobalamin by the LAB isolates was quantified by High Performance Liquid Chromatography (HPLC) analysis. The four LAB species which were isolated from the sample were used as a consortium for fresh milk fermentation to determine the production potency of folate and cobalamin by the LAB isolates. Increase in the vitamin contents ofthe fermented product was observed with the concentration of folate increasing from 0.1652 mg/ml in unfermented milk to 0.4283 mg/ml after fermentation by the LAB isolates. This presented a 60.38% increase in the folate content of the milk sample, thereby signifying that there was a high potency of the LAB isolates to produce folate. Also, cobalamin content increased from 0.0194 mg/ml in unfermented milk to 0.0403 mg/ml after LAB fermentation (51.86% increase). Therefore, it can be concluded that the isolated LAB from fermented milk have the potency to produce folate and cobalamin as there were significant increases in the vitamin contents of milk fermented with the LAB isolates compared to unfermented milk. These LAB species can serve as a better choice as starter culture for the formation of other dairy fermented products rather than their traditional starters, which may consume these vitamins.