A combined PCR and selective enrichment method for rapid detection of Listeria monocytogenes |
| |
Authors: | S Fitter M Heuzenroeder CJ Thomas |
| |
Institution: | Department of Microbiology and Immunology, University of Adelaide, Adelaide, Australia;Division of Clinical Microbiology, Institute of Medical and Veterinary Science, Adelaide, Australia |
| |
Abstract: | Development of a routine detection assay for Listeria monocytogenes in foods that uses the polymerase chain reaction (PCR) and enrichment cultures was investigated. Oligonucleotide primers were chosen to amplify a 3'region of L. monocytogenes hly A gene spanning a conserved Hin dIII site. PCR detection sensitivity for L. monocytogenes in dilutions of pure enrichment cultures was between 50 and 500 colony forming units. A short enrichment period before PCR amplification allowed detection of the organisms in a range of complex foods contaminated with 104 cfu/g. Detection sensitivity for the assay in the presence of chicken skin and soft cheese was determined at 10–100 cfu/g. Utilization of enrichment cultures and PCR allowed identification of the organism within 24 h or 2 days. |
| |
Keywords: | |
|
|