ABSTRACT

This study aimed at isolating and identifying LAB from traditionally fermented foods in Nigeria (ogi, kunu zaki and akpu) and to evaluate their probiotic potentials invitro. Nine lactic acid bacteria were isolated from the selected sources. These isolates were then screened for their phenotypic and biochemical properties. The selected isolates were then identified molecularly using the 16SrRNA sequencing as Bacillus spp (3), Lactobacillus fermentum (3 strains) and Lactococcus lactis (2 strains) and their partial sequence were deposited in the Gene Bank. Among the LAB isolates that were identified, 3 isolates Lactobacillus fermentum CS19, Lactococcus lactis, and Lactobacillus fermentum exhibited invitro safety attributes and were able to survive inhibitory conditions like acid environment and 0.3%bile salt. Furthermore, they demonstrated bactericidal activity against some selected drug-sensitive and multi-drug resistant pathogens (Salmonella typi, Escherichia coli and Staphylococcus aureus) capable of causing infection in both gastro intestinal tract and skin. Lactobacillus fermentum CS19 demonstrated the highest antibacterial activity against the selected food pathogens with the highest activity being recorded Salmonella typhi (15.33±1.52mm) and Staphylococcus aureus (15.33±1.15mm). Among the selected isolates Lactobacillus fermentum CS19 demonstrated highest hydrophobicity and adhesion to mucin. However, this study suggests that the LAB isolates Lactobacillus fermentum CS19, Lactococcus lactis, and Lactobacillus fermentum are good probiotic strain and could be introduced in starter cultures in traditionally feremented foods.