鱼腥草与左氧氟沙星联合应用对生物被膜细菌的清除作用

目的探讨鱼腥草对细菌生物被膜的影响,观察鱼腥草与左氧氟沙星联合应用对铜绿假单胞菌(Pseudomonas aeruginosa,PA)生物被膜的作用.方法用试管二倍稀释法测定鱼腥草和左氧氟沙星的最低抑菌浓度;用平板培养法建立生物被膜细菌体外模型;用MTT活菌计数法测定存活细菌数;用扫描电镜观察药物对生物被膜的破坏及清除作用.结果铜绿假单胞菌培养7 d后可形成稳定的生物被膜.鱼腥草或左氧氟沙星单独作用,对生物被膜的形态及存活细菌数无明显改变.二者联合应用,能破坏生物被膜的结构,显著降低膜内存活细菌数.结论鱼腥草与左氧氟沙星联合运用对生物被膜细菌具有协同杀灭作用.

Germicidal Actions of the Combination of Herba Houttuyniae and Levofloxacin on Bacterium with Biological Envelope

Objective To investigate the synergic bactericidal activity of Herba Houttuyniae combined with levofloxacin on the biological envelope of mucoid Pseudomonas aeruginosa(PA).Methods MIC (minimal inhibitory concentration) was determined by using tube doubling dilution method. In-vitro biological envelope models of PA were established by plate cultivation method. The bacterial colony were counted by MTT method. The morphology of biological envelope were observed under scanning electronic microscope (SEM) .Results On the 7th day of cultivation,the stable biological envelope formed.Herba Houttuyniae or levofloxacin alone had no effect on the biological envelope or the number of surviving bacterial colony. The combination of the above two could destroy the structure of biological envelope and decrease the number of surviving bacterial colony.Conclusion Herba Houttuyniae combined with levofloxacin has synergistic germicidal actions on biological envelope of PA.