Abstract
A methodology with rapidity and specificity is of great significance for effectively control and management of disease epidemics caused by Salmonella enterica as it has presented an obvious threat to food safety and public health worldwide. One major drawback to the traditional cross-priming amplification (CPA) detection method is the possibility of detecting false-positive signals derived from opening tube lids or non-specific amplification, and molecular beacon was firstly employed to solve aforementioned problems. The reaction system was optimized and the results showed that the MB-CPA method was highly specific for detection of S. enterica. The LOD of established assay was found to be 10 CFU/mL, 40 CFU/mL, 4 CFU/mL in pure culture, chicken sample without and with 6 h enrichment, respectively. And the LOD of MB-CPA was 10 times higher than that of real-time PCR. An application of MB-CPA assay was conducted with 78 naturally contaminated food samples to test its practicality. After an enrichment step at 37℃ for 6h, the results showed 100% sensitivity and 100% specificity compared with standard culture-based method. Considering its rapidity, user-friendliness, cost-effectiveness, this MB-CPA assay will aid in the broader application in food industry for the detection of S. enterica in small or resource-limited food testing laboratories.