实时荧光PCR法检测食品中亚利桑那沙门氏菌

Detection of Salmonella arizonae in food by real-time PCR

沙门氏菌(Salmonella)是食品检测过程中最常见的致病菌之一,亚利桑那沙门氏菌(Salmonella arizonae)又是沙门氏菌中比较难鉴定的亚种。该实验通过实时荧光聚合酶链式反应(PCR)方法快速准确的检测亚利桑那沙门氏菌和其他沙门氏菌。根据GenBank公布的亚利桑那沙门氏菌和其他沙门氏菌gud D基因序列,分别设计引物和Taqman探针。使用10株不同血清型的沙门氏菌标准菌株、88株沙门氏菌分离株和29株食品中常见食源性致病菌进行实时荧光PCR特异性实验。结果显示,该实验所设计的引物探针特异性非常好。实时荧光PCR灵敏性试验结果表明,检测灵敏度可达到1～10 CFU/m L的添加浓度。经模拟污染样品验证,所建立的实时荧光PCR方法与传统方法的检测结果相一致,具有检测周期短、操作简便的优势。

Salmonella is one of the most common foodborne pathogens in food testing process, and Salmonella arizona is a subspecies that are comparatively difficult to identify. The method of real-time polymerase chain reaction（PCR） for detection of S. arizonae and other Salmonella spp. was established in this study. According to gud D gene sequences of S. arizonae and other Salmonella spp. published in GenBank, PCR primers and Taqman probe sequences were designed. 10 strains of Salmonella with different serotypes, 88 strains of Salmonella isolates and 29 strains of common food-borne pathogenic bacteria were detected and identified by the real-time PCR method, and the results showed that the specificity of the primers was very good. The results of real-time PCR amplification sensitivity tests showed that the detection sensitivity can reach 1-10 CFU/ml. According to the verification of the simulated pollution samples, the established real-time PCR method was consistent with the traditional testing results, with the advantages of short testing cycle and easy to operate.