耐药基因可通过垂直传播和水平传播等途径在微生物的种内和种间进行传递,食用受到耐药菌污染的食品,具有威胁人类健康的潜在可能。为建立耐药基因快速检测方法并应用于食源性微生物耐药基因的筛查,对食源性耐药菌在食品中的存在状况、耐药种类进行了探讨。采集了3个不同菜市场的9份食品样本,对食源菌进行了分离培养,使用四环素、链霉素、红霉素、氯霉素、甲氧苄胺嘧啶进行抗性菌筛选,并利用聚合酶链式反应(PCR)技术及环介导等温扩增(LAMP)法对8种抗性基因进行筛查,同时用实时荧光定量技术对结果进行了验证。9份食品样本中,菌落总数在105CFU/g至107CFU/g。红霉素抗性的菌落数最多,除1份样本外均在105CFU/g以上;氯霉素抗性菌菌落数最低,除1份样本之外均在103CFU/g以下。在对8种耐药基因筛查时发现,在四环素抗性菌中耐药基因tetA阳性率最高,为75.56%。采用LAMP法筛查耐药基因,阳性率高于PCR法。结果表明,具有抗药性的食源菌在样本中大量存在,这提示食品可以作为抗性菌存在和传播的重要介质。而LAMP作为一种简单、快速的基因检测技术可以用于耐药基因的快速筛查,为了解抗性菌在食品加工环境的污染和分布情况,以及消杀防控措施的采取和评估提供了基础信息。

Background: The antibiotic resistance gene can be transmitted perpendicularly and horizontally.It is a possible threat to human if food contaminated by the resistant pathogens is consumed.Purpose: To establish a method for antibiotic resistant genes detection with Loop-Mediated Isothermal Amplification method,and to investigate the prevalence of antibiotic resistance genes in the food-borne microbiology.Method: Nine food samples were collected and the antibiotic resistance microbiology and resistant genes were screened by culture,PCR and LAMP method,Real-time PCR was used for results verification.Results: The total numbers of colonies were between 105 CFU/g and 107 CFU/g.The number of erythromycin-resistance colonies was more than 105 CFU/g,except one sample.The number of tetracycline-resistance colonies was less than 103 CFU/g,except one sample.The positive rate of tetA gene was the highest,75.56%.In addition,the positive rate of LAMP was higher than PCR method.Conclusions: According to the data in this study,the large numbers of antibiotic resistance bacteria were present in the food samples.Food can be an important medium in spreading the resistant bacteria.LAMP as a simple,rapid gene detection technique can be used for rapid screening of resistant genes and the basic information of prevention measures can be provided.Also,the LAMP method can be used to find out the environmental pollution of resistance bacteria in food processing and distribution.