Metabolic Profiling and Antimicrobial Activity of Limosilactobacillus fermentum MB1: Implications for Food Biopreservation.

Food spoilage caused by microbial contamination remains a significant challenge throughout the food production, processing, and storage chain, contributing substantially to global food waste and economic losses. In this study, L. fermentum MB1 was isolated from home-made curd and systematically evaluated for its probiotic and bio-active properties. The strain exhibited survival under acidic conditions (pH 2.0-3.0), moderate hydrophobicity (28.00-31.66%), and progressive auto-aggregation (29.00% at 12 h). It also showed strong co-aggregation with foodborne pathogens and was confirmed as γ-hemolytic, indicating safety. Antibacterial assays revealed broad inhibitory activity against both Gram-positive and Gram-negative food pathogens, while antifungal tests demonstrated effectiveness against common food spoilage fungi. Metabolite characterization through FTIR, HPTLC, and HR-LCMS confirmed the presence of diverse bioactive compounds. Additionally, the strain inhibited quorum-sensing-regulated traits, including biofilm formation, pigment production, and bacterial motility. Overall, these findings establish L. fermentum MB1 as a functionally strong probiotic candidate with significant potential for food biopreservation and the development of natural antimicrobial alternatives.