IUN-FAN LEI¹*, PAUL ROFFEY², CHRIS BLANCHARD² AND KEN GU¹

(Received: June 29, 2007; Accepted: December 21, 2007)

   This study developed a multiplex PCR method for the screening and detection of six common foodborne pathogens in Macao. The m-PCR procedure, which uses six pairs of primers, produced specific amplicons of the expected sizes from mixed populations of reference bacterial strains in food samples and from pure cultures.  The verocytotoxin (stx) gene of Escherichia coli O157: H7, the hemolysin (hly) gene of Listeria monocytogenes, the invasion (invA) gene of Salmonella spp., the cholera toxin (ctx) gene of Vibrio cholerae, the thermolabile hemolysin (tlh) gene of V. parahaemolyticus, and the thermostable nuclease (nuc) gene of Staphylococcus aureus were used as target genes for m-PCR detection.  The detection limit of the assay for the bacterial targets was 1-100 cfu per mL.  The m-PCR analysis was designed for three main food clusters; meat and meat products testing for Salmonella spp., L. monocytogenes, and E. coli O157: H7, seafood and seafood products testing for V. cholerae and V. parahaemolyticus and ready-to-eat foods testing for S. aureus.  Overall, results of the present study indicate that the m-PCR is a potential technique for the rapid detection of foodborne bacteria for routine monitoring and risk assessment of food.