Biotransformation-Driven Improvement of Flavor and Bioactivity by Lactiplantibacillus plantarum BUCM-1 in Mung Bean Beverage via Fermentation

Directed fermentation has emerged as a key strategy for enhancing the sensory quality and health benefits of plant-based foods. However, the mechanisms by which specific microbial strains remodel metabolic networks within complex plant matrices to co-regulate flavor formation and bioactive compound accumulation remain unclear. In this study, Lactiplantibacillus plantarum BUCM-1, a strain with lipid-lowering potential isolated from traditional fermented foods, was employed to establish a directed fermentation model for mung bean beverage. Integrated multi-omics analyses revealed that BUCM-1-dominated fermentation reshaped both the volatile and non-volatile metabolic profiles, accompanied by enhanced in vitro lipid-lowering activity, with lipid reduction improving from 26% to 88%. Off-odor compounds were suppressed, while aroma-active compounds were enriched. At the non-volatile level, biotransformation was mainly centered on amino acid metabolism and the tricarboxylic acid cycle. Notably, the aspartate–ornithine metabolic axis was strongly activated, with aspartate and ornithine increasing by approximately 7- and 30-fold, respectively, suggesting enhanced coupling between nitrogen metabolism and central carbon metabolism during fermentation. Overall, this study demonstrates that fermentation with BUCM-1 enables the synergistic improvement of flavor quality and functional activity in a high-protein plant substrate. These findings provide mechanistic insights and a metabolomics-guided strategy for developing functional plant-based fermented beverages with controllable flavor and targeted health benefits.