Production of virulence factors in S. aureus is controlled by global regulators such as agr and sarA [13]. agrA encodes accessory gene regulator A; when agrA expression is inhibited, production of virulence factors is also inhibited. In addition, sarA regulates the production of some matrix adhesion genes (e.g., fnbA) and exotoxin genes (e.g., hla), the virulence factors associated with adherence of S. aureus [25]. Our investigation of the expression of the agrA and sarA genes in this study showed that A. princeps inhibited sea expression at concentrations higher than 1 mg/mL.