ABSTRACT

The aim of this study was to compare the antibiotic susceptibility of eighty Escherichia coli isolates from vegetables and food products of animal origin in Tunisia, and to study their genes encoding antibiotic resistance and in vitro biofilm forming capacity. Antimicrobial susceptibilities were determined, as well as PCR investigation of genes associated with antibiotic resistance. Biofilm formation was tested using four different methods: the microtiter plate-, MTT-staining-, XTT-staining-, and the Congo Red Agar assays. High antibiotic resistance rates were observed for amoxicillin (68.7%), amoxicillin/clavulanic acid (73.7%), gentamicin (68.7%), kanamycin (66.2%), nalidixic acid (36.2%), streptomycin (68.7%) and tetracycline (35%). The majority of isolates was multidrug resistant and biofilm producer. MTT testing showed that vegetables isolates were significantly higher biofilm producers compared to foods of animal origins. This study showed that E. coli isolates from food products were reservoirs of genes encoding antibiotic-resistance and have a high propensity to produce biofilm.

摘要

本研究的目的是比较突尼斯从蔬菜和动物源性食品中分离出的 80 株大肠杆菌的抗生素敏感性，并研究其编码抗生素抗性的基因和体外研究。生物膜形成能力。确定了抗生素敏感性，并对与抗生素耐药性相关的基因进行了 PCR 研究。使用四种不同的方法测试生物膜形成：微量滴定板、MTT 染色、XTT 染色和刚果红琼脂测定。阿莫西林 (68.7%)、阿莫西林/克拉维酸 (73.7%)、庆大霉素 (68.7%)、卡那霉素 (66.2%)、萘啶酸 (36.2%)、链霉素 (68.7%) 和四环素 (35) 的抗生素耐药率较高%）。大多数分离株是耐多药和生物膜生产者。MTT 测试表明，与动物源性食品相比，蔬菜分离物的生物膜产生量明显更高。本研究表明，大肠杆菌 来自食品的分离物是编码抗生素抗性基因的储存库，并且具有产生生物膜的高倾向。