Subinhibitory concentrations of farrerol reduce α-toxin expression in Staphylococcus aureus.

In this study, the antibacterial activity of farrerol against Staphylococcus aureus was determined. The minimum inhibitory concentrations capable of inhibiting 35 S. aureus strains ranged from 4 to 16 μg mL(-1) . A haemolysis assay, Western blot and real-time reverse transcriptase-PCR assay were performed to identify the influence of subinhibitory concentrations of farrerol on the secretion of α-toxin by S. aureus. The results show that farrerol significantly decreased, in a dose-dependent manner, the production of α-toxin by both methicillin-sensitive S. aureus and methicillin-resistant S. aureus.