Bacteriocin Production by Lactococcus garvieae MF098136.1 Isolated from Locally Fermented Foods for Food Preservation

Abstract

Bacteriocins are natural antimicrobial peptides primarily produced by lactic acid bacteria (LAB). This study focused on the production of bacteriocins from LAB isolated from locally fermented Nigerian foods. Isolation of LAB was performed on anaerobic de Man, Rogosa, and Sharpe agar (MRS) agar at 37°C for 72 hours, followed by morphological, biochemical and molecular characterization. The bacteriocins were produced from the LAB, optimised, purified and tested against food spoilage bacteria. The proximate composition was determined and the toxicological examination of the bacteriocin was evaluated in albino rats. A total of 50 LAB isolates were obtained. The LAB with the best potential was identified as Lactococcus garvieae MF098136.1 and exhibited significant antibacterial activity against pathogens isolated from the food samples. The optimal bacteriocin production by L. garvieae MF098136.1 reached maximum activity at pH 5.28, 72 hours incubation, and 20°C. Purification processes enhanced bacteriocin specific activity up to 12.7 AU/mg but reduced overall yield (23–55%). Toxicological evaluation in albino rats at doses up to 5000 mg/kg revealed no mortality or significant adverse effects. The bacteriocin significantly suppressed microbial load in stored Akamu and Masa, compared to controls. Additionally, the bacteriocin treatments enhanced sensory properties and overall acceptability.