Conventional and molecular characterization of selected Lactic acid bacteria from fermented corn gruel (ogi) and fermented milk (nono)

Abstract

Fermented foods have served as important vehicle for microbial flora that have overtime formed a niche as part of the human diet. One of such is the Lactic acid bacteria which are nonpathogenic, extensively disseminated and keenly included in most fermentative procedures. This research was conducted to isolate lactic acid bacteria from fermented food sources. Pour plate method was used for the isolation of bacteria on MRS media. The bacteria isolates obtained from fermented corn gruel (ogi) and fermented milk (nono) were characterized through conventional and molecular methods. A total of six (6) bacteria isolates were recovered and identified to reveal a community of bacteria dominated by Lactobacilli sp and Bacillus sp. Specie identification was based on sequence analysis of 16SrRNA gene resulting in 4 Lactobacilli sp made up of 1 L. plantarum, 2 L acidophilus, 1 L. fabifermentan and 1 Bacillus sp. However, one of the isolates was identified as coccobacilli due to its peculiar structure on the basis of its microscopy and biochemical reaction only. The mean total aerobic bacteria plate count ranged from 2.0×10² cfu/g to 6.5x10⁴ cfu/g. Studies continue to portray lactic acid bacteria as the predominant group of microorganisms that have undergone several studies for food fermentation and have been used extensively as potential sources of probiotics for the production of functional foods.