Foodborne Pathog Dis 2020 07 31;17(7):447-458. Epub 2020 Jan 31.
Shanxi Key Laboratory of Environmental Veterinary Medicine, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China.
, a highly virulent food-borne pathogen transmitted through food, can cause severe infectious diseases in a large number of people through a single outbreak, due to its low infective doses. In this study, a flow cytometry (FCM)-based method was developed for the rapid detection of single viable cells with dual staining of fluorescein isothiocyanate (FITC)-labeled anti- antibody and propidium iodide (PI) dyes. The FCM-based method includes 6 h of pre-enrichment, 40 min of target cell isolation, and 20 min of dual staining and FCM analysis. The developed method demonstrated high specificity for the detection of 23 strains and 22 food-borne pathogenic non- strains. Furthermore, the analyses of 30 samples of milk powder artificially contaminated with single cells, 123 samples of retail milk powder, and 6 samples of -positive milk powder were performed by the FCM-based as well as traditional plate-based methods for testing the efficiency of the methods. The two methods yielded similar results for the detection of pathogens in all milk powder samples. In conclusion, the developed FCM-based method was found to be efficient in detecting single viable cells in milk powder within 7 h. The proposed dual-color FITC assay combined with pre-enrichment offers a great potential for the rapid and sensitive detection of other pathogens in dairy products.