Effect of Rosmarinus officinalis L. Fractions on Antimicrobial Activity against Methicillin- resistant Staphylococcus aureus (MRSA) and Resistant Genes Regulation

摘要

This study was performed to evaluate antimicrobial activity of methanol extract from Rosmarinus officinalis L. and their fractions on methicillin-resistant Staphylococcus aureus (MRSA) and resistant gene regulation. The methanol extract of Rosmarinusofficinalis L. and their hexane fractions showed the strongest antimicrobial activity against S. aureus and MRSA. To observe the morphological change of MRSA according to the hexane fraction 80 iig/mL treatment, scanning electron microscope (SEM) of MRSAwere measured. The results from SEM showed decreased number of bacteria, lysis and damaged cell wall. Expressions of MecA and penicillinase were substantially decreased in a dose-dependent manner on MRSA that had been treated with methanol extract of Rosmarinus officinalis L. and their hexane fractions.