Screening of Lactic Acid Bacteria Isolates for Antifungal Activity as a Potential Starter Culture in Alibo Production

The study aimed to isolate and characterize lactic acid bacteria (LAB) from fermented maize (Zea mays) and retted cassava (Manihot esculenta), assessing their potential as starter cultures and antimicrobial agents. LAB were isolated using selective culture techniques, and their morphological, physiological, and biochemical properties were determined. The isolates were identified as Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus fermentum, Lactobacillus acidophilus, and Leuconostoc mesenteroides based on carbohydrate fermentation patterns using the API 50 CHL system. Quantitative analysis revealed that the isolates produced lactic acid, hydrogen peroxide, and diacetyl, which are key antimicrobial metabolites. L. plantarum (LM8) and L. brevis (LM26) showed the highest lactic acid production, contributing to significant pH reduction. Antifungal activity assays demonstrated inhibition against food spoilage fungi, including Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Penicillium citrinum, and Fusarium species, with L. brevis (LM26) and L. acidophilus (LC5) exhibiting the strongest antagonistic effects. The findings suggest that these LAB strains have promising applications as starter cultures for controlled food fermentations and natural preservatives for food safety enhancement. Further research is recommended to optimize their fermentation conditions, evaluate their probiotic potential, and explore their commercialization in the food industry.