小檗碱对金黄色葡萄球菌生物被膜的抑制作用

Inhibitory Effect of Berberine on the Biofilm of Staphylococcus Aureus

本实验以中药提取物小檗碱为研究对象,探究其对金黄色葡萄球菌生物被膜形成的抑制作用。实验采用常量肉汤稀释法测定小檗碱对金黄色葡萄球菌的最小抑菌浓度(MIC);随后分别选取2 MIC、1 MIC、0.5 MIC浓度小檗碱,采用结晶紫染色法测定其对金黄色葡萄球菌生物被膜生长的抑制率,同时采用实时荧光定量PCR测定2 MIC、1 MIC、0.5 MIC小檗碱对金黄色葡萄球菌Nuc基因的表达情况。结果显示,小檗碱对金黄色葡萄球菌的最小抑菌浓度(MIC)为62.5μg/mL,2 MIC、1 MIC、0.5 MIC浓度小檗碱对金黄色葡萄球菌生物被膜的抑制率分别为77.14%、66.91%和55.55%,荧光定量PCR测得各组金葡菌Nuc基因的Ct值大小为Ct值(0.5 MIC)> Ct值(1.0 MIC)>Ct值(2 MIC),说明随着小檗碱浓度的增大,对金黄色葡萄球菌生物被膜的抑制作用增强,呈现明显的浓度依赖性。本研究为小檗碱对金黄色葡萄球菌感染的防治提供数据支持。

This experiment takes berberine,a traditional Chinese medicine extract,as the research object to explore its inhibitory effect on the formation of biofilm of Staphylococcus aureus(S.aureus).The minimum inhibitory concentration(MIC)of berberine against Staphylococcus aureus was determined by broth dilution method.Subsequently,2 MIC,1 MIC and 0.5 MIC concentrations of berberine were selected respectively,and the inhibition rate of berberine on the growth of Staphylococcus aureus biofilm was determined by crystal violet staining.At the same time,the expression of Nuc gene of Staphylococcus aureus was determined by real-time fluorescence quantitative PCR.The results showed that the minimum inhibitory concentration(MIC)of berberine on Staphylococcus aureus was 62.5μg/mL.The inhibition rates of berberine at 2 MIC,1 MIC and 0.5 MIC on Staphylococcus aureus biofilm were 77.14%,66.91%and 55.55%,respectively.The Ct value(0.5 MIC)>Ct value(1.0 MIC)>Ct value(2 MIC)of each group was measured by fluorescence quantitative PCR,indicating that the inhibition effect on the biofilm of Staphylococcus aureus increased with the increase of berberine concentration,showing a significant concentration dependence.This study provides data support for the prevention and treatment of Staphylococcus aureus infection with berberine.