绿原酸对聚氯乙烯生物材料表面金黄色葡萄球菌生物被膜的抑制作用

Inhibitory Effect of Chlorogenic Acid on Biofilm Formation of Staphylococcus aureus on Polyvinyl Chloride Biomaterial

目的探讨金银花主要活性成分绿原酸对聚氯乙烯(PVC)生物材料表面金黄色葡萄球菌(S.a)生物被膜(BF)的体外抑制作用。方法采用肉汤-医用PVC薄片系统构建早期及成熟期的S.a BF体外模型,并用扫描电镜(SEM)鉴定;试管兑倍稀释法测定绿原酸的最低抑菌浓度;将实验对象分为空白对照组、绿原酸(0.125,0.25,0.5,1,2mg/ml)组;荧光正置相差显微镜观察BF形态学改变;结晶紫染色法定量载体表面生物总量;连续稀释法计数BF内活菌。结果成功在PVC生物材料表面建立不同时期的S.a BF;无论早期或成熟期,当绿原酸浓度达到0.5mg/ml及以上时,荧光显微镜下均可观察到PVC载体表面BF的形成较同期空白组明显减少,结晶紫染色法定量及BF内活菌计数均少于同期空白对照组(P<0.05)。结论金银花主要活性成分绿原酸可抑制PVC生物材料表面S.a BF的形成,且在一定浓度范围内随着绿原酸浓度增加,其对BF抑制作用增强。

Objective To investigate the inhibitory effect of chlorogenic acid on biofilm （BF） formation of Staphylococcus aureus （S. a） on polyvinyl chloride biomaterial in vitro. Methods The early and matured S. a BF models were established in vitro re- spectively, using the broth and PVC biomaterial slices. Scanning electron microscope （SEM） was used to confirm the BF formation. The minimum inhibitory concentration was determined by tube broth dilution method. Then the BF models were divided into control group and ehlorogenic acid groups. The morphological change of BF on the PVC biomaterial surfaces was observed under phase contrast fluorescent microscopy. Crystal violet assay was used to quantify the biomass and viable bacterial colony counts in BF were recorded by serial dilution method. Results The early and matured S. a BF models were established on the PVC biomaterial surface successfully. The fluorescent microscope observation revealed that the early and matured BFs formed in the ehlorogenic acid groups with final concentration meeting or exceeding 0. 5mg/ml were significantly less than those in the control groups, with their BF quantitation and viable bacterial colony counts significantly decreasing compared with the control groups （ P 〈 0.05 ）. Conclusion Chlorogenie acid can inhibit the S. a BF formation on PVC biomaterial surface, and the inhibitory effect was gradually enhanced with its concentration increasing in a certain range.