Multi-omics reveals dynamic succession and correlations between bacterial communities and metabolites in Luoyang mung...

Continuous propagation of Luoyang mung bean sour (LMBS) was employed to simulate industrial production, establishing a stable microbial ecosystem within 18 days that mimicked the characteristics of mature LMBS. To investigate the mechanisms of LMBS formation, the changes and correlations between metabolic profiles and the bacterial community were analyzed during continuous propagation. Through high-throughput sequencing, this study revealed that Lactobacillus became the dominant genus, accounting for 85 % of the bacterial community, and overwhelmed other genera, such as Leuconostoc (0.20 %), Lactococcus (1.19 %), and Acetobacter (8.01 %) after 9 days. Metabolomics analysis identified a total of 2379 differential metabolites. The top 30 metabolites comprised peptides (γ-glutamyl-S-methylcysteine, γ-Glu-Leu), organic acids (indoleacrylic acid, tricarballylic acid), and flavonoids (vitexin, isovitexin). The relative abundance of peptides and flavonoids increased at post-fermentation, including Gly-Tyr-His, Arg-Ile-His, and apigenin. Metabolic pathway analysis indicated that protein degradation and amino acid metabolism were the primary pathways, with a focus on tryptophan metabolism and arginine biosynthesis. Key metabolites-organic acids, peptides, flavonoids, antibiotics, and carbohydrates-also exhibited strong correlations with dominant genera (|r| > 0.7). By elucidating potential regulatory relationships between dominant genera and metabolites, this study provides a foundation for future LMBS industrialization.