The impact of Staphylococcus saprophyticus on the fermentation of cigar filler tobacco leaves and the dynamics of microbial community

Comparative experiments employing metagenomic sequencing and gas chromatography-mass spectrometry demonstrated that exogenous Staphylococcus saprophyticus significantly increased the accumulation of aromatic compounds, particularly alcohols, ketones, and aldehydes, in the later stages of fermentation. LEfSe analysis indicated a restructuring of the microbial community, with Bacillus emerging as a key differential genus. Spearman correlation analysis revealed a positive correlation between Staphylococcus and Bacillus, while both genera negatively correlated with most other genera. Additionally, Staphylococcus correlated positively with key aromatic compounds. Functional annotation (KEGG and EGGNOG) showed that exogenous microorganisms enhanced carbohydrate and amino acid metabolic pathways, while CAZy analysis indicated increased glycosyltransferases and carbohydrate-binding modules, facilitating sugar conversion and utilization.