Antimicrobial activity of xanthones from Calophyllum species, against methicillin-resistant Staphylococcus aureus (MRSA)

During the Fast 5 years, a considerable number of known and new xanthones f rom the Calophyllum species of Sri Lanka have been isolated and characteriz ed. We have investigated the antimicrobial activity of Calophyllum xanthone s, with a special reference to methicillin-resistant Staphylococcus aureus (MRSA). These activity studies were carried out using the agar plate method . Calozeloxanthone, a xanthone which has been isolated from C. moonii and C . lankensis, showed the highest activity against methicillin-resistant S. a ureus (MRSA) strains at a concentration of 8.3 mu g/ml. Hence, calozeyloxan thone appears to hold promise as an antimicrobial agent in the treatment of infections with S. aureus, including methicillin-sensitive S. aureus (MRSA ), and should be investigated further. (C) 1999 Elsevier Science Ireland Lt d. All rights reserved.