Anti–Biofilm Potential of Daucosterol against Staphylococcus aureus

Staphylococcus aureus causes various foodborne illnesses and poses a serious threat to human health by contaminating the food supply chain during production, processing, distribution and marketing. S. aureus is capable of forming biofilms and contributing to polymicrobial infections, which are resistant to antimicrobial agents and challenging to treat. Therefore, developing anti–biofilm agents to which this bacterium cannot easily acquire resistance is a highly desirable treatment approach. In this study, we performed high-throughput screening to identify novel inhibitors of S. aureus ATCC 25923 biofilm formation using a library of 680 natural compounds, with a DMSO-treated sample as a control. Daucosterol, which exhibited significant inhibition of biofilm formation, was selected for further investigation of its antibacterial activity and biofilm detachment effects. S. aureus was treated with different concentrations of daucosterol (5~1,000 μM) to evaluate its growth inhibition, and no growth defects were observed even at 1,000 μM. However, biofilm formation was significantly inhibited at 200, 500, and 1,000 μM daucosterol, with reductions of 54.84%, 32.29%, and 26.87%, respectively (p < 0.05). When preformed biofilms were treated with daucosterol, biofilm biomass was reduced by 71.08% (p < 0.001), confirming statistically significant degradation of biofilm. These results suggest that daucosterol, a natural compound with both biofilm formation inhibition and degradation effects, does not affect the growth of S. aureus. Therefore, it has the potential to be used as a control agent against foodborne pathogens, with a lower risk of inducing resistance.