中药对鸡致病性大肠埃希菌的体外抑菌试验

为研究25种中药对秦皇岛地区鸡致病性大肠埃希菌(Escherichia coli)地方流行株QH1(O78)、QH2(O89)、QH4(O1)的体外抑菌效果,以E.coli标准株ATCC25922作为质控菌株。利用水提法制备中药药液,使终浓度为1g/mL;用平板琼脂打孔法和改良微量二倍稀释-平板法分别测定25种中药的抑菌圈直径和最小抑菌浓度(MIC)。结果表明,金银花、黄连、乌梅、五味子4种中药对鸡致病性E.coli地方株极度敏感,抑菌圈直径在20.3mm~22.7mm之间,其MIC在15.65mg/mL~31.25mg/mL之间;其他药物对鸡致病性E.coli地方株有不同程度的敏感性,为鸡致病性E.coli地方株中药防治提供理论基础。

Antibacterial Effects of Chinese Herbal Medicines on Pathogenic Escherichia coli in Chickens in Vitro

In this study,the in vitro antibacterial effects of 25 Chinese herbal medicines on the local epidemic strains of pathogenic Escherichia coli isolated from chickens in Qinhuangdao area were analyzed.The Chinese medicine solutions were prepared by the water extracting,and the concentration of the solution was diluted to 1 g/mL.The diameter of the inhibition zone was measured by the agar diffusion plate method.The minimum inhibitory concentration (MIC) was determined by modified trace dilution method and plate method.The results showed that the local strains of pathogenic E.coli were extremely sensitive to 4 kinds of Chinese medicines,such as Lonicera japonica,Coptis chinensis,Prunus mume and Schisandra chinensis.The MIC of 4 kinds of extremely effective Chinese medicines were from 15.65 to 31.25 mg/mL;Other drugs had different degrees of sensitivities to the local strains of pathogenic E.coli.In conclusion,four kinds of Chinese medicines had good antibacterial effects on the local strains of pathogenic E.coli and it provided a theoretical basis on prevention and control of the local strains of pathogenic Escherichia coli by Chinese medicines.