黄连素联合左氧氟沙星对肺炎克雷伯菌的体外抑菌研究

In vitro antibacterial effect of berberine on K. Pneunmoniae combing with levofloxacin

目的探讨黄连素联合左氧氟沙星对肺炎克雷伯菌(KPn)抑菌作用。方法 KPn分为敏感株组和耐药株组,采用琼脂二倍稀释法测定黄连素联合左氧氟沙星对KPn的最低抑菌浓度(MIC)、抑制99%接种细菌生长的最低抑菌浓度(MIC99)、防突变浓度(MPC);比浊法测定黄连素联合左氧氟沙星对KPn生长曲线的影响。结果与单用左氧氟沙星相比,联合黄连素后,敏感株组和耐药株组对左氧氟沙星MIC的下降率分别为33.3%和20%,2组之间无统计学差异(P>0.05)。左氧氟沙星与50μg/m L黄连素或500μg/m L黄连素联用后的抗菌能力均较单用左氧氟沙星好,且高浓度黄连素的联合抑菌效果较低浓度更加明显,差异有统计学意义(P<0.05)。与50μg/m L黄连素联用后,左氧氟沙星SI下降了1/5;而与500μg/m L黄连素联用则下降3/5。结论本实验证明了黄连素与左氧氟沙星联用能增加左氧氟沙星对KPn的抗菌作用,可以明显缩小耐药突变选择窗(MSW),且高浓度黄连素联合抗菌作用较低浓度好。

Objective To explore antibacterial effect of berberine（Ber） on K. Pneunmoniae（KPn） combing with levofloxacin（LVX）. Methods KPn was divided into sensitive and resistant strains groups. The MIC,MIC99 and MPC of Ber combing with LVX on KPn was determined by the agar dilution method. The growth curve of Ber combing with LVX on KPn was measured by turbidimetry. Results Ber combined with LVX compare with LVX alone,MIC descent rate of sensitive strains group was 33. 3%,resistant strains group was 20%,and there were no statistical differences along two groups（P〈0. 05）. Ber combined with LVX could increase antibacterial effect and high concentration was more obvious than the low one,there were statistical differences（P〈0. 05）. Compared with LVX alone,the SI value of 50 μg/m L Ber combined with LVX was decreased 1/5,and the SI value of 500 μg/m L Ber combined with LVX was decreased 3/5. Conclusion Ber combing with LVX could increase bacteriostatic effect on KPn,and reduce MSW significantly; high concentration of berberine was better than low one.