Inhibitory Effect of Newly-Synthesized Chalcones on Hemolytic Activity of Methicillin-Resistant Staphylococcus aureus

Abstract

Pathogenicity of methicillin-resistant Staphylococcus aureus (MRSA) is associated with a broad spectrum of virulence factors, amongst which is a-hemolysin. The aim of this study was to investigate the effect of three newly-synthesized chalcones (1,3- Bis-(2-hydroxy-phenyl)propenone, 3(3-Hydroxy-phenyl)-1-(2-hydroxy-phenyl)-propenone and 3-(4-Hydroxy-phenyl)-1-(2-hydroxy-phenyl)-propenone) on a-hemolysin production of clinical isolates of MRSA. Subinhibitory concentrations of the tested compounds reduced hemolytic activity of MRSA strains, with almost complete abolishment of hemolysis at concentrations in the range of 1/2-1/4 x MIC (25-12.5 mu g/ml). In conclusion, newly-synthesized chalcones tested in this study showed potent inhibitory activity on a-hemolysin production of multiresistant and genetically diverse MRSA strains.