Bioexploration of Traditional Fermented Foods for Isolation, Characterization and Functional Evaluation of Lactic Acid Bacteria

Probiotics are live microbes that provide health benefits to the host when administered in sufficient numbers. Lactobacillus is among the most widely studied probiotic genera due to its safety profile and functional properties. This study aimed to isolate and characterize Lactobacillus species from fermented indigenous foods, including, Idli batter, toddy, dhokla, and Mishti Doi, and to assess their probiotic potential through phenotypic, biochemical, and molecular characterization. Isolation was performed using MRS media. Gram staining and microscopic analysis confirmed the presence of Gram-positive, rod-shaped, non-spore-forming bacteria. Further phenotypic assessment was conducted using a battery of biochemical tests, including haemolysis, arginine hydrolysis, NaCl tolerance (6.5%), citrate utilization, and various tests. The isolates exhibited typical biochemical profiles and robust tolerance to varying salt concentrations, indicating their ability to survive the physiological stresses of the gastrointestinal tract. To achieve definitive taxonomic identification, the isolates underwent molecular characterization via 16S rRNA gene sequencing. This research highlights the potential of local fermentation practices in contributing to global health through the identification of superior, high-viability probiotic candidates. Lactic acid bacteria were successfully isolated from selected fermented food samples using selective media such as MRS agar. The project successfully showed that traditional fermented foods are a valuable source of the probiotic lactobacillus strains with promising antimicrobial properties. Future research can be focused on molecular identification, advanced probiotic characterization, in vivo validation and development of functional food products using the isolated strains. Genomic studies and large- scale industrial applications can further enhance their commercial potential.