环介导等温扩增技术快速检测食品中的单增李斯特氏菌

Rapid Detection of Listeria Monocytogenes in Food by Loop-Mediated Isothermal Amplification Technique

采用环介导等温扩增(1oop-mediated isothermal amplification,LAMP)技术检测食品中的单增李斯特氏菌,并做特异性、敏感性和适用性试验。试验结果显示以单增李斯特氏菌hly基因保守区设计特异性引物,进行DNA等温扩增是可行的。3株单增李斯特氏菌均扩增出特异性目的片段,而10株非单增李斯特氏菌均未产生目的片段。用环介导等温扩增法在65℃条件下,1h内可检出单增李斯特氏菌,其灵敏度达100cfu/mL,特异性为100%,无假阳性和假阴性出现。用该方法与国标方法分别检测50种样品中的单增李斯特氏菌,结果数据显示两种方法的符合率达100%,表明环介导等温扩增法具有高效、特异性强和敏感性高等特点,可满足大批量样品快速筛选的要求。

A Loop-mediated isothermal amplification（LAMP） method for detection of Listeria monocytogenes（LM） in food and its specificity,sensitivity,and potential usefulness were investigated in this paper.The results showed that the method was available with specific primers from conserved regions of LM hly genes,and the expected fragments were produced from 3 strains of LM,while not from 10 strains of other pathogenic bacteria.The LM could be rapidly and specifically detected by LAMP method within 1 hour at constant temperature of 65 ℃.The sensitivity of the LAMP method to detect LM was at the level of 100 cfu/mL and the specificity of the approach was 100% without any false negative or positive action.The detection tests of 50 kinds of food samples with the developed method and the National Standard method was finished,and the results showed that the coincidence rate of these two methods was 100%.All of that demonstrated that the LAMP method is high effective,specificity and sensitivity for the detection of LM,and available for tast screening of LM in a large number of food samples.