金银花主要活性成分对烟曲霉生物膜的体外影响

The effect of the main active component of Honeysuckle on Aspergillus fumigatus biofilm in vitro

目的探讨金银花主要活性成分绿原酸(CRA)对烟曲霉(A.f)生物膜(BF)的体外影响。方法扫描电镜(SEM)鉴定体外烟曲霉BF;二倍稀释法测定绿原酸的最低抑菌浓度(MIC)及最低杀真菌浓度(MFC);各浓度的CRA分别作用于BF 48h后,XTT减低法测定生物膜内菌细胞的代谢活力;结晶紫(CV)法定量生物膜。结果受试菌株经过培养24h、48h后可形成稳定的BF。药物作用48h后,各浓度CRA对菌体代谢活力与空白组相比差异均无统计学意义(P>0.05);较高浓度的CRA组(256、512、1 024μg/ml)生物膜量与空白组相比,差异有统计学意义(P<0.05)。结论烟曲霉体外经培养24h、48h后可形成稳定生物膜;金银花主要活性成分绿原酸不能杀死烟曲霉生物膜细胞,但可以抑制生物膜胞外基质的形成,其抑制作用呈浓度依赖性。

Objective To explore the effect of the main active component of Honeysuckle （Chlorogenic acid,CRA） on Aspergillus fumigatus （A.f） biofilm （BF） in vitro. Methods The model of A. fumigatus BF was established in vitro and i-dentified by scanning electron microscopy （SEM）. The minimum inhibitory concentration （MIC） and the minimum fungicidal concentration （MFC） were measured by double dilution. After affecting 48 hours, the XTT reduction assay was used for the metabolic activity of the fungus inside biofilm. The crystal violet（CV） assay was used for quantification of biofilm. Results BF model was established successfully in vitro after being cultured for 24h and 48h. After affecting 48h , the metabolic activity by XTT assay showed that there was no significant difference among untreated control and CRA groups; there was statistically sig-nificant difference between the biofilm biomass of serially increasing concentrations CRA （256,512,1 024μg/ml） and untreated control （P〈0.05）. Conclusion Aspergillus fumigatus can form biofilms in vitro after affecting 24h and 48h; the main active component of Honeysuckle（chlorogenic acid） can inhibit the extracellular matrix of BF in vitro,which showed a dose-dependent manner.