Multi-omics investigation of microbial community dynamics and metabolic regulation in mulberry wine fermentation under temperature and acid stress

This study employed an integrated approach of metagenomics and metabolomics to investigate microbial community dynamics during mulberry wine fermentation under varying temperatures (17-29 °C) and pH levels (3.0-4.5). Twenty treatment combinations, spanning 27 days, captured the temporal dynamics of microbial communities and metabolic activity. Environmental stress significantly shaped community assembly, with Saccharomyces cerevisiae acting as the dominant fermentation organism and Lactobacillus spp. associated with organic acids. Core population analysis revealed specialized functions in ethanol production, acid resistance, and flavor biosynthesis. An optimal fermentation efficiency of 82 % and an ethanol content of 9.1 % vol. were achieved with the response surface method, resulting in optimal fermentation conditions of 23 ± 1 °C with a pH of 3.5 ± 0.1. Multi-omics correlation network analysis revealed coordinated associations among gene expression, enzymatic activities, and metabolite profiles, including coordinated expression patterns of flavor compound biosynthesis pathways. This research provides evidence-based optimization strategies for industrial mulberry wine production, enhancing understanding of stress-responsive microbial adaptation mechanisms.