Isolation, Identification and Characterization of Potential Probiotics from Fermented Food Products

Abstract

Potential probiotics were isolated, identified and characterised from ogi, fufu, nunu, palmwine and fermented tigernut milk. Pour plate method was used for the isolation of lactic acid bacteria (LAB) on De Man Rogosa Sharpe (MRS) media. Three (3) pure colonies were distinctly obtained from each of the fermented food sources with microbial mean counts ranging from 8.13 - 8.25 Log10 Cfu/ml. Isolated strains were identified and characterized using morphological, API-50 CHL (Bio-merieux, France) and Polymerase chain reaction (PCR) analysis. Ten (10) of the isolated microorganisms were identified as Lactobacilli, two (2) Micrococci and a Lactococcus. The Lactobacilli were catalase negative and oxidase negative rod-shaped bacteria. The identification accuracy of the isolates based on similarities from the computer-aided API and PCR GenBank databases ranged from 49.00 - 99.90% and 79.00 - 99.00% respectively. The amplification pattern of the 16S regions of the sequenced isolates showed DNA fragments with 500 - 1000 base pairs. The LAB strains identified are Lactobacillus fermentum NBRC 15885, Leuconostoc mesenteroides LM, Lactobacillus plantarum CIP 10315.1, Lactobacillus plantarum NBRC 15891, Lactobacillus parabuchneri LMG 11457, Lactobacillus pentosus 124-3 and Lactobacillus brevis ATCC 14869. These strains had high correlation in both the API and PCR identification techniques that was used in this study. Potential probiotic lactic acid bacteria can be isolated and identified from ogi, fufu, nunu, paimwine and fermented tigernut milk.