Isolation of Lactobacilus Fermentum as Probiotics for Aquaculture from some Indigenous Fermented Food Products in Nigeria

Abstract

Abstract

This study aims to evaluate the probiotic and antimicrobial properties of Lactobacillus fermentumisolated from some indigenous fermented food products- Ogi(fermented corn OG), Wara (fermented milk W) and Fufu (fermented cassava FU). The isolates were evaluated for their tolerance to low pH, bile salt, antimicrobial potential, tolerance to high temperature and osmotic pressure. The isolates from these fermented products with best antimicrobial properties were identified using PCR amplification and sequencing of 165 rDNA. Results showed that total of 135 isolates were cocci or rod shaped, gram positive, haemolysis negative and catalase negative and these were identified as lactic acid bacteria. Most of the isolates showed strong antibacterial activity to A. hydrophila, E coli, and Salmonella, however only Fu 9 (Lactobacillus fermentum strain F4S8) and OG 1 (Lactobacillus fermentum strain BCS27) showed higher zones of inhibition against all the pathogenic organism which is a good sign of a potential probiotics candidate and they were further identified using PCR techniques. Identification by 165 rDNA sequences showed the two isolates were identified as Lactobacillus fermentum with Fu 9 identified as Lactobacillusfermentum strain F4S8 and OG 1 Lactobacillus fermentumstrainBCS27withasimilarityindexofapproximately 99-100%.