Sanchen powder extract combined with vancomycin against methicillin-resistant Staphylococcus aureus

摘要

Objective: To explore the effects of the extract of Sanchen powder(ESCP) combined with vancomycin on methicillin-resistant Staphylococcus aureus(MRSA) planktonic cells, biofilms, and virulence factors.Methods: The herbs in Sanchen powder(SCP) were extracted separately with 50% ethanol. Then, the content of hydroxysafflower yellow A(HSYA) and cholic acid in the extract of artificial cattle bezoar(artificial Calculus bovis) and safflower(Carthamus tinctorius L.) was measured by ultraviolet visible-vis spectrophotometry and high-performance liquid chromatography. The effects of ESCP combined with vancomycin on MRSA by observing its biofilm viability were assessed using a 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium5-carboxanilide reduction assay and scanning electron microscopy.Additionally, enzyme activity was measured by plasma coagulase test and DNase test.Results: The cholic acid content of the artificial C. bovis extract was 7.34(0.81) mg/g, and the HSYA content of the C. tinctorius extract was 9.18(0.09) mg/g. The minimal inhibitory concentrations of ESCP and vancomycin were 25.6 mg/m L and 2 μg/m L. The minimum bactericidal concentration of ESCP was51.2 mg/m L. ESCP combined with vancomycin could inhibit the expression of coagulase and bacteria in mature biofilms. Neither ESCP nor vancomycin had a significant effect on DNase.Conclusion: This study is the first to show that ESCP combined with vancomycin inhibits coagulase and MRSA embedded in mature biofilms and that it represents a promising treatment for MRSA infection.