Rapid polymerase chain reaction/DNA probe membrane-based assay for the detection of Listeria and Listeria monocytogenes in food

We describe the development of polymerase chain reaction (PCR)/DNA probe me mbrane-based colorimetric assays for the detection and identification of Li steria and L. monocytogenes. PCR primers designed from the 16S to 23S rRNA intergenic spacer region amplified products that were reverse hybridized to membrane-bound oligonucleotide probes specific for Listeria and L. monocyt ogenes with a detection limit of 1 to 10 CFU/25 mi in inoculated raw and pa steurized milk samples. These qualitative assays have the potential to be i ntegrated into testing laboratories for monitoring the microbiological qual ity of foods.