Short communication: N-Acetylcysteine–mediated augmentation of β-lactam antibacterial activity against methicillin-resistant Staphylococcus aureus isolated from bovine mastitis cases

Abstract

The present study investigated the effects of N-acetylcysteine (NAC) on β-lactam antibacterial activity against 20 methicillin-resistant Staphylococcus aureus (MRSA) isolates from bovine mastitis. Minimum inhibitory concentrations (MIC) were determined by the E-test method. The presence of 10 mM NAC reduced the MIC of penicillin, ampicillin, oxacillin, cefoxitin, ceftazidime, and cefotaxime to MRSA. Importantly, the MIC of cefoxitin in MRSA in the presence of NAC was lower than the susceptible breakpoint of cefoxitin. The results provide a new way to use current β-lactam antibiotics combined with NAC against MRSA.