【摘要】 目的　比较传代前后细菌对抗生素和中药耐受性的变化 ,探讨细菌的耐药性机制。方法　分别在含有新霉素和中药的培养基中对大肠杆菌进行连续传代培养 ,然后在空白LB中再次传代 ,最后测定其最低抑菌浓度 (MIC)。结果　在含新霉素培养条件下很容易筛选出对自身和其他几种抗生素耐受性明显提高的细胞 (多重抗性 ) ,而相同条件下中药培养菌则没有表现出对自身和新霉素等抗生素耐受性的提高。在新霉素选择压力下获得的耐药性细菌群体 ,在去除选择压力后 ,对新霉素的敏感性可基本恢复到出发水平。结论　细菌群体对抗生素耐受性的提高是不稳定的 ,抗生素的间歇或轮换使用有助于减缓细菌耐药性产生更多还原

【Abstract】 AIM Objective By comparing E.coli’s resistance to antibiotics and Chinese medical herbs before and after incubated in LB containing Neomycin or Chinese medical herbs, we try to understand the difference in their mechanism of resistance. METHODS We incubated E.coli cells under the culturing media with low concentration of Neomycin and Chinese medicine herbs respectively; lately, the culturing process were continued under the media with no Neomycin or Chinese medicine herbs. We tested the minimal inhibitory concentrations(MIC)of Neomycin(Kanamycin, Gentamicin, Tetracyclin etc) and Chinese medical herbs to culture cells. Result The experimental data indicated that increased resistance of population cells in the broth including Neomycin happened easily, as well as multi resistance simultaneously. As for the Chinese medical herbs, the case is different. After growing in the LB containing one of Huang Lian (rhizoma coptidis), Berberine or San-Huang-Tang of low concentrations, population cells did not increase their resistance either to antibiotics or to Chinese medical herbs. Removing the pressure of Neomycin, E.coli population cells resistance came back to the initial level. CONCLUSION The increased antibiotic resistance of population cells is unstable, and alternative using of different antibiotics maybe contribute to the alleviation of antibiotics resistance.更多还原