Anti-biofilm effects of sinomenine against Staphylococcus aureus

Staphylococcus aureus is a gram-positive foodborne pathogen capable of forming strong biofilms. This study identified that anti-biofilm natural compound against S. aureus. Sinomenine, a natural compound, showed significantly reduced biofilm formation (31.97-39.86%), but no effect on bacterial growth was observed. The dispersion of preformed biofilms was observed by confocal laser scanning microscopy (CLSM). qRT-PCR revealed that sinomenine treatment significantly up-regulated agrA by 3.8-fold and down-regulated icaA gene by 3.1-fold. These indicate that sinomenine treatment induces biofilm dispersal due to cell-cell adhesion, polysaccharide intercellular adhesin (PIA), and phenol-soluble modulin (PSM) peptides production. Our results suggest that sinomenine can be used as a promising agent for effectively controlling biofilm formation and dispersion, thereby making S. aureus more susceptible to the action of antimicrobial agents.