Objective To determine the antimicrobial activity of rosemary (Rosmarinus officinalis L.) and to investigate the synergistic effects of this extract combined with ceforuxime against methicillin-resistant Staphylococcus aureus (MRSA).
Methods The inhibitory and bactericidal activities of rosemary ethanol extract, alone and in combination with cefuroxime, were studied.
Results The minimum inhibitory concentrations (MICs) of the ethanol extract of rosemary were in the range of 0.39–3.13 mg/mL. The minimum bactericidal concentrations (MBCs) were usually equal to or double that MICs. The antimicrobial activity of combinations of the ethanol extract of rosemary and cefuroxime indicated their synergistic effects against all MRSAs.
Conclusions The present work clearly demonstrates that rosemary has a key role in the elevation of susceptibility to β-lactams.