多重耐药与药物敏感大肠杆菌菌株在体外模拟胃肠道环境的生存力研究

目的 大肠杆菌是人和温血动物肠道重要的兼性厌氧寄居菌群, 也是水源和食品粪便污染指示菌。研究多重耐药型大肠杆菌和药物敏感型大肠杆菌菌株在体外模拟胃肠道环境下的生存能力, 本文数据为控制有害大肠杆菌提供理论依据。方法 从奎屯市超市采集30份零售食品, 分离出8份大肠杆菌阳性样品, 污染率为27%。利用纸片扩散法对分离的8株大肠杆菌进行耐药实验, 从8株菌中选出1株具有多重耐药的E27号菌和1株药物敏感型菌株E25号菌进行人工胃液和人工肠液耐受试验。结果 所测定的8株大肠杆菌对大多数耐药纸片敏感, 大肠杆菌对氨苄西林和四环素耐药率较高。8株菌中有4株耐药菌和4株敏感菌。结论 所选出的两株菌, E25在人工胃肠液中的耐受力较好, 菌株E27在人工胃肠液中耐受力较差, 敏感菌株E25要比多重耐药菌株E27菌数减少的缓慢。

Study on viability of multiple drug-resistant and sensitive Escherichia coli in vitro gastrointestinal environment

Objective Escherichia coli is human and warm blooded animal intestinal important facultative anaerobic microflora group. It is indicator bacteria of water and food fecal pollution. The viability of multiple drug-resistant and drug sensitive Escherichia coli in vitro gastrointestinal environment was studied. The results provided a theoretical basis for control of harmful Escherichia coli. Methods The 30 retail food were collected from supermarkets of Kuitun City, the 8 positive samples were identified. The contamination rate was 27%. Then the disk diffusion method was used to conduct the drug test for 8 E.coli strains isolated from 8 positive samples respectively. A multi-drug resistant E.coli E27 and a drug sensitive E.coli E25 were implemented in artificial gastric juice and the intestinal juice by tolerance test. Results The results show that the measured eight E.coli were sensitive to most drugs. The resistant bacteria were keeping resistance for ampicillin and tetracycline. There were four drug-resistant bacteria and four sensitive bacteria. Conclusion The tolerance was good for E.coli E25 in vitro gastrointestinal juice. And the tolerance was not high for E.coli E27 in vitro gastrointestinal juice. The decreasing trend of sensitive bacteria E25 was slower than multi-drug resistant bacteria E27.