A Real-Time PCR Assay for the Detection of Salmonella in a Wide Variety of Food and Food-Animal Matrices

Authors: Bohaychuk, V.M.¹; Gensler, G.E.¹; McFall, M.E.¹; King, R.K.¹; Renter, D.G.²

Source: Journal of Food Protection®, Volume 70, Number 5, May 2007 , pp. 1080-1087(8)

Publisher: International Association for Food Protection

Buy & download fulltext article:

Price: $37.00 plus tax (Refund Policy)

Abstract:

Conventional culture methods have traditionally been considered the ''gold standards'' for the isolation and identification of foodborne pathogens. However, culture methods are labor-intensive and time-consuming. We have developed a real-time PCR assay for the detection of Salmonella in a variety of food and food-animal matrices. The real-time PCR assay incorporates both primers and hybridization probes based on the sequence of the Salmonella invA gene and uses fluorescent resonance energy transfer technology to ensure highly sensitive and specific results. This method correctly classified 51 laboratory isolates of Salmonella and 28 non-Salmonella strains. The method was also validated with a large number of field samples that consisted of porcine feces and cecal contents, pork carcasses, bovine feces and beef carcasses, poultry cecal contents and carcasses, equine feces, animal feeds, and various food products. The samples (3,388) were preenriched in buffered peptone water and then selectively enriched in tetrathionate and Rappaport-Vassiliadis broths. Aliquots of the selective enrichment broths were combined for DNA extraction and analysis by the real-time PCR assay. When compared with the culture method, the diagnostic sensitivity of the PCR assay for the various matrices ranged from 97.1 to 100.0%, and the diagnostic specificity ranged from 91.3 to 100.0%. Kappa values ranged from 0.87 to 1.00, indicating excellent agreement of the real-time PCR assay to the culture method. The reduction in time and labor makes this highly sensitive and specific real-time PCR assay an excellent alternative to conventional culture methods for surveillance and research studies to improve food safety.

Document Type: Research article

Affiliations: 1: Agri-Food Laboratories Branch, Food Safety Division, Alberta Agriculture and Food, 6909-116 Street, Edmonton, Alberta, Canada T6H 4P2 2: Department of Diagnostic Medicine/Pathobiology, 307 Coles Hall, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66506, USA

Publication date: 2007-05-01

More about this publication?

IAFP members must first sign in on the right to access full text articles of JFP

First published in 1937, the Journal of Food Protection^®, is a refereed monthly publication. Each issue contains scientific research and authoritative review articles reporting on a variety of topics in food science pertaining to food safety and quality. The Journal is internationally recognized as the leading publication in the field of food microbiology with a readership exceeding 11,000 scientists from 70 countries. The Journal of Food Protection^® is indexed in Index Medicus, Current Contents, BIOSIS, PubMed, Medline, and many others.

Print and online subscriptions are available to Members and Institutional subscribers. Online visitors who are not IAFP Members or journal subscribers will be charged on a pay-per-view basis. Information can be obtained by calling +1 800.369.6337; +1 515.276.3344; fax: +1 515.276.8655, E-mail: info@foodprotection.org or Web site: www.foodprotection.org
Information for Authors
Submit a Paper
Subscribe to this Title
Membership Information
Information for Advertisers
ingentaconnect is not responsible for the content or availability of external websites

A Real-Time PCR Assay for the Detection of Salmonella in a Wide Variety of Food and Food-Animal Matrices

Buy & download fulltext article:

Tools

Key

Text size:

Useful pages