Omics Reveals the Antibacterial Mechanism of Dihydromyricetin and Vine Tea Extract Against Staphylococcus aureus via Cell Wall and Membrane Disruption

Staphylococcus aureus (S. aureus) is a common pathogen that threatens healthcare and food safety. Vine tea extract (VTE) and its major active component, dihydromyricetin (DMY), show antibacterial activity. However, their mechanisms of action are not fully understood. In this study, we combined proteomics and lipidomics, with RT–qPCR validation of selected differentially expressed genes, to investigate how DMY and VTE affect S. aureus. Proteomics identified 210 and 535 differentially expressed proteins (DEPs) in the DMY-treated and VTE-treated groups, respectively. These DEPs were mainly enriched in cell wall- and membrane-associated pathways. DMY markedly increased proteins involved in fatty acid degradation, glyceride metabolism, and cell wall synthesis. In contrast, VTE increased proteins related to heme/iron acquisition and cell wall degradation. In addition, VTE altered proteins involved in pyrimidine metabolism and aminoacyl-tRNA biosynthesis, suggesting that non-DMY components in VTE may contribute to the antibacterial activity through additional pathways. Lipidomics further indicated membrane lipid remodeling, including increased fatty acid unsaturation and shorter acyl chain length. Collectively, DMY and VTE may inhibit S. aureus growth by remodeling membrane lipids and disturbing cell wall–cell membrane homeostasis. These findings provide mechanistic support for further development of DMY and VTE as natural antimicrobial candidates.