22味中药对犊牛腹泻大肠杆菌的体外抑菌试验

Antibacterial test in vitro of 22 traditional Chinese medicines on Escherichia coli from calf with diarrhea

开展了乌梅、白头翁、黄连、穿心莲等22味中药对犊牛腹泻大肠杆菌的体外抑菌试验。按照常规法制备中药水提物,采用平板打孔法和微量稀释法测定了22味中药对犊牛腹泻大肠杆菌的抑菌圈直径、最低抑菌浓度(MIC)和最小杀菌浓度(MBC)。结果显示,22味中药中有10味中药对犊牛腹泻大肠杆菌有抑菌作用,其中乌梅、诃子、五倍子和半边莲对犊牛腹泻大肠杆菌的抑菌作用最佳,抑菌圈直径为15 mm以上,为高度敏感;其次是黄连、秦皮、穿心莲、连翘、金银花、石榴皮,抑菌圈直径均大于10 mm,为中度敏感;黄柏、紫花地丁等12味中药对犊牛腹泻大肠杆菌无抑菌作用。对五倍子、乌梅、诃子和半边莲等抑菌作用较好的中药可进一步开展研究。

In order to study the antibacterial effect in vitro of 22 tradition Chinese medicines such as Fructus mume,Radix pulsatillae,Copis rool and Andrographis paniculata on Escherichia coli from calf with diarrhea,the aqueous extract of Chinese herbal medicines was prepared according to the conventional method.The diameter of the antibacterial circle,the minimum inhibitory concentration(MIC)and the minimum bactericidal concentration(MBC)were determined by the plate drilling method and the microdilution method.The results showed that 10 of the 22 traditional Chinese medicines had antibacterial effect on Escherichia coli from calf with diarrhea,among which Fructus mume,Fructus chebula,Gall chinensis and Lobelia chinensis had the best efficacy with the diameter of antibacterial circle more than 15 mm,which were highly sensitive;followed by Coptis rool,Cortex fraxini,Andrographis paniculata,Fructus forsythiae,Lonicerae japonicae and Pomegranate peel with the diameter of the antibacterial circle greater than 10 mm,which were moderately sensitive;12 traditional Chinese medicines such as Phellodendron chinensis cortex and Herba biolae had no antibacterial effect on E.coli causing calf diarrhea.It shows that different traditional Chinese medicines have different antibacterial effects in vitro on Escherichia coli from calf with diarrhea.Traditional Chinese medicines with good antibacterial effects such as Gall chinensis,Fructus mume,Fructus chebula and Lobelia chinensis can be used for further research.