Inhibition Of Baicalin、Baicalein On Staphylococcus Aureus Biofilm In Vitro

Staphylococcus aureus is the common gram-positive bacteria which cause clinically pyogenic infection,it is also the common pathogen of hospital acquired infection.The infection rate of staphylococcus aureus has rised year by year because the medical implanted materials and anbiotics widely used.Mutipal drug resistance of staphylococcus aureus and MRSA detection rate also increased.The mechanism of staphylococcus aureus resistcance is very complicated, which is mainly related to penicillin bingding protein PBP2a mutation,beta-lactamenzyme production,active efflux pump system oversxpression,ribosomal target change,bacterial biofilm formation.Biofilm is a major factor causes staphylococcus aureus drug resistcance,which is a research hotspot.Research has showed that Pseudomonas aeruginosas biofilm fomation can be inhibited by scutellaria aqueous-extracts.Baicalin and Baicalein are the major active component of scutellaria.Therefore an model of static biofilm was established with the optimal conditions in vitro,then baicalin、 baicalein were added into the medium respectively to inhibit biofilm formation at the beginning of the modeling PARTIThe Establishment Of Staphylococcus Aureus Biofilm ModelOBJECTIVES To establish the staphylococcus aureus BF model in vitro,then study the intervention of the drugs on the biofilm.METHODS1、 The staphylococcus aureus biofilm was qualitatived by Congo red agar method.2、The staphylococcus aureus biofilm model was established in vitro and observed by silver staining method.RESULTS1、The colony on the congo red medium was black, surrounding medium of colony fade,as positive strains of biofilm formation.2、Cultured3days,the carrier of silver staining was observed under light microscopy,visiable cottonwood-like BF,transmittance decrease; cultured7days, the carrier of silver staining was observed under light microscopy,visible volume mass, cottonwood-like BF,transmittance further decrease.CONCLUSIONS1、The number of17546staphylococcus aureus strains was positive strains by which biofilm can be established after congo red agar qualitative.2、With poly vinyl chloride as carrier,0.5%dextrose trytone soy broth as medium, biofilm can be established by number of17546staphylococcus aureus strains in vitro. PART ⅡThe Inhibition Of Baicalin、Baicalein On Staphylococcus Aureus Biofilm In VitroOBJECTIVES To study the inhibition of baicalin、 baicalein on staphylococcus aureus biofilmMETHODS1、 The minimum inhibitory concentration(MIC) of baicalin、 baicalein against number of17546staphylococcus aureus strains were detected by double dilution method.2、The research was divided into control group、baicalin group and baicalein group.The drugs were added into the medium respectively at the beginning of the biofilm formation modeling.,then the medium was changed per48h,cultured3days and7days, respectively.The biofilm was observed by silver staining、Fluorescence Microscope (FM);Viable bacterial counts was determined by serial dilution;and Crystal violet staining method was used for biofilm quantitation.RESULTS1、 The minimum inhibitory concentration of baicalin、 baicalein on number of17546staphylococcus aureus strains were2048ug/ml、256ug/ml,respectively.2、Biofilm and viable bacterial counts of number of17546staphylococcus aureus strains adhered to the surface of catheter in baicalin group、baicalein group were less than the control group after incubated for3d and7d(P<0.05).CONCLUSIONS The BF formed by number of17546staphylococcus aureus strains can be inhibited by baicalin、baicalein in vitro.