Metabolomic analysis of antimicrobial mechanism of polysaccharides from Sparassis crispa based on HPLC-Q-TOF/MS.

Abuse of antibiotics makes antibiotic-resistance become a huge challenge in bacterial infection treatment. The discovery of new antibiotics is of great significance to human health. In this study, the antibacterial mechanism of Sparassis crispa polysaccharides (SCPs) was explored. The SCPs isolated from Sparassis crispa was composed of fucose, glucose and galactose with a molar ratio of 0.043 : 0.652: 0.305. Bacteriostatic tests showed SCPs inhibited the growth of Staphylococcus aureus better than Escherichia coli's, and damage to bacteria was observed under scanning electron microscopy. Metabolomic analysis based on HPLC-Q-TOF/MS indicated that SCPs disrupted metabolism of the glycolysis and tricarboxylic acid cycle pathways in S. aureus. The variations of fructose-1,6-diphosphate, 1,3-diphosphoglycerol, succinate and oxaloacetate were significant, whose systematic changes accompanied with decrease of ATP in cells indicated that SCPs could exert antibacterial effects by inducing dysfunction of catabolism and energy metabolism. Our research confirmed the antibacterial properties of SCPs and provided a perspective for understanding antibacterial mechanism of polysaccharides from natural products through metabolomics technology.