一种富集即食肉制品中单核细胞增生李斯特氏菌的方法

A method for Enriching Listeria Monocytogenes in Ready-Made Meat Products

研究一种能够有效富集即食肉制品中单核细胞增生李斯特氏菌的方法,用于提高肉制品中单核细胞增生李斯特氏菌的检测灵敏度和检出限。通过对样品预处理缓冲液种类和浓度、样品过滤条件、微孔滤膜材质和孔径、滤膜洗脱液种类及浓度的选择,确定即食肉制品富集单核细胞增生李斯特氏菌的条件。通过敏感性和特异性试验,与国标方法的对比验证试验,确定其准确性和灵敏性。结果显示样品预处理缓冲液选择李氏增菌肉汤LB3和Hanks的混合液(1:1),2℃低温条件下静置60 min后,于4℃10000 r/min离心10 min去除脂肪和大分子蛋白质,采用Φ50 mm 0.8μm聚醚PES微孔滤膜抽滤富集目标菌于Φ55 mm 50 mL具塞平底玻璃杯中,滤膜用10m L洗脱液(5 mL Hanks+5 mL LB3)洗脱即得到样品富集待测液。采用该方法用于即食肉制品中单核细胞增生李斯特氏菌的快速检测效果最佳。建立了最佳的富集即食肉制品单核细胞增生李斯特氏菌的方法,提高了方法的检出限和灵敏度。

A method for enriching Listeria monocytogenes in ready-made meat products was researched to improve the detection sensitivity and detection limit of Listeria monocytogenes in meat products.The conditions for enrichment of Listeria monocytogenes in ready-made meat products were determined by selecting the types and concentrations of buffer,the filter conditions,the material and pore size of microporous membrane,and eluent types and concentrations.The accuracy and sensitivity of the method were determined by sensitivity and specificity tests and comparison with the national standard method.Result show the mixture of Listeria enrichment broth LB3 and Hanks(1:1)was selected as the sample pretreatment buffer.The samples were placed at 2℃for 60 minutes and centrifuged at 4℃10000 r/min for 10 minutes to remove fat and macromolecular proteins.Polyether PES microporous membrane with diameter of 50 mm and pore diameter of 0.8μm was used to extract and enrich the target bacteria in a glass with a flat bottom,the sample solution which to be test was enriched by eluting with 10 mL eluent(5 mL Hanks+5 mL LB3).The above method is the best for rapid detection of Listeria monocytogenes in ready-made meat products.The best method for enriching Listeria monocytogenes in ready-made meat products was established,and the detection limit and sensitivity of the method were improved.