环介导等温扩增技术检测不同乳制品常见食源性致病菌

Detection of common food borne pathogens in different dairy products by loop-mediated isothermal amplification

目的验证环介导等温扩增技术(loop-mediated isothermal amplification, LAMP)试剂和仪器在不同乳制品常见食源性致病菌检测中的应用效果。方法针对不同乳制品中常见食源性致病菌,运用LAMP建立便捷、快速、高效地检测方法,并以实验室储备菌株及人工污染乳制品样品评价LAMP检测引物试剂和仪器在快速筛查中的适用性。结果选用的引物试剂仅对目标菌株核酸产生扩增,其余菌株无扩增,扩增检测灵敏度均达101fg/μL。用国家标准法和LAMP方法同时检测婴幼儿奶粉、奶酪样品,检测结果完全一致,对发酵奶样品进行检测时大肠杆菌O157:H7和金黄色葡萄球菌也呈现出良好的检测结果。检测总耗时不超过30 min。结论采用的GenieⅡ实时荧光检测仪操作简单,便携轻便,可实时监测不同乳制品中的大肠杆菌O157:H7、金黄色葡萄球菌及沙门氏菌污染,特异性强、敏感度高,适合企业批量现场快速检测。

Objective To verify the application effect of loop-mediated isothermal amplification(LAMP) detection reagents and instruments for the detection of common food borne pathogens in different dairy products. Methods Aiming at common foodborne pathogens in different dairy products, LAMP was used to establish a convenient, rapid and efficient detection method. The applicability of LAMP detection primer reagents and instruments in rapid screening were evaluated by laboratory reserved strains and artificially contaminated dairy samples. Results The selected primers could only amplify the nucleic acid of the target strain, and the other strains had no amplification. The detection sensitivity of amplification was 101 fg/μL. The national standard method and LAMP method were used to detect infant milk powder and cheese samples at the same time, and the detection results were completely consistent. When the fermented milk samples were detected, Escherichia coli O157: H7 and Staphylococcus aureus also showed good detection results. The total test time was less than 30 min. Conclusion The genie II real-time fluorescence detector is easy to operate and portable, and has strong specificity, high sensitivity, fast and accurate. It can monitor Escherichia coli O157: H7, Staphylococcus aureus and Salmonella in different dairy products in real time, which is suitable for enterprises to conduct rapid detection in batches.