Development of a Rapid Screening Test for Listeria monocytogenes in Raw Chicken Meat Using Loop-Mediated Isothermal Amplification (LAMP) and Lateral Flow Dipstick (LFD)

A loop-mediated isothermal amplification and lateral flow dipstick (LAMP-LFD) protocol was established for the rapid detection of the foodborne pathogen Listeria monocytogenes based on detection of the phosphatidylcholine-phospholipase C gene (plcB). The LAMP-LFD method achieved results within 90 min and consisted of a one-step DNA extraction followed by LAMP and LFD. The detection limits of the assay using L. monocytogenes purified genomic DNA or cells from a pure culture were 800 fg and 2.82 CFU mL(-1), respectively. The specificity test revealed that the method exhibited no cross-reactivity with other Listeria species (Listeria innocua DMST 9011, Listeria ivanovii DMST 9012, Listeria welshimeri DMST 20559) or non-Listeria spp. (Salmonella ssp., Shigella spp., Campylobacter spp., Escherichia coli ATCC 25922, Bacillus cereus, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Micrococcus luteus, Citrobacter diversus, Serratia marcescens, Enterobacter aerogenes, and Klebsiella oxytoca). Compared to standard culture analysis, the specificity, sensitivity, and accuracy of the LAMP-LFD method in tests of 200 raw chicken meat samples were 100, 90.20, and 97.50%, respectively. Thus, LAMP-LFD is a promising point-of-care diagnosis tool for decision-making for controlling of L. monocytogenes-contaminated food products, decreasing mortality rates, and improving the quality of life.