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Comparison of conventional and molecular methods for the routine confirmation of Listeria monocytogenes in milk products produced domestically in Croatia

Published online by Cambridge University Press:  23 November 2009

Jadranka Frece ,
Ksenija Markov ,
Domagoj Čvek ,
Kristina Kolarec  and
Frane Delaš
Jadranka Frece*
Affiliation:
Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia
Ksenija Markov
Affiliation:
Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia
Domagoj Čvek
Affiliation:
Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia
Kristina Kolarec
Affiliation:
Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia
Frane Delaš
Affiliation:
Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Croatia
*
*For correspondence; e-mail: jgoreta@pbf.hr
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Abstract

Conventional methods for the identification of Listeria in foodstuffs are generally cumbersome and time consuming. The use of primary enrichment in half strength Fraser broth and the use of PALCAM agar were assessed in comparison with API Listeria and polymerase chain reaction (PCR) for their ability to accurately detect and confirm the presence of List. monocytogenes in milk products. The aim of our work was to detect List. monocytogenes in domestic unpasteurised milk, fresh cheese and cream of raw milk taken from four different district of Zagreb-Croatia using conventional (microbiological and biochemical – API test) and PCR methods. Of the 180 milk products samples tested, 27·6% were presumptively positive for Listeria on PALCAM agar. Only 21·3% of samples were confirmed to be positive for Listeria by API Listeria test, and 17·3% were confirmed to be positive for List. monocytogenes by PCR amplification of the hly gene (64 bp). PCR was able to eliminate the false positive and detect all List. monocytogenes in the milk products, unlike the conventional methods used in the industry. These results indicate a low presence of this pathogen in this area (Zagreb) of Croatia. PCR proves to be a sensitive and rapid technique to be included in the procedure of detection of List. monocytogenes in food products and this method is considerably faster than current standard methods.

Keywords

Listeria monocytogenesPCRmilk products
Type
Research Article
Information
Journal of Dairy Research , Volume 77 , Issue 1 , February 2010 , pp. 112 - 116
Copyright
Copyright © Proprietors of Journal of Dairy Research 2009

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References

Anon 2005 EN ISO 11290-1:1996/A1:2004 Microbiology of Food and Animal Feeding Stuffs – Horizontal method for the Detection and Enumeration of Listeria monocytogenes, Part 1: Detection method Amendment 1: Modification of the Isolation Media and the Haemolysis Test, and Inclusion of Precision data. Brussels: European Committee for StandardizationGoogle Scholar
Chaturongakul, S & Boor, KJ 2006 Sigmaβ activation under environmental and energy stress conditions in Listeria monocytogenes. Applied and Environmental Microbiology. 72(8) 5197–5203CrossRefGoogle Scholar
FDA 2007 FDA and CDC remind consumers of the dangers of drinking raw milkGoogle Scholar
Frece, J 2007 Synbiotic activity of bacteria: L. acidophilus M92, L. plantarium L4 and E. taecium L3. Dissertation, Faculty of Food Technology and Biochemistry, University of Zagreb, Croatia.Google Scholar
Frece, J, Kos, B, Svetec, IK, Zgaga, Z, Mrša, V & Šušković, J 2005 Importance of S-layer proteins in probiotic activity of Lactobacillus acidophilus M92. Journal of Applied Microbiology 98 285–292Google Scholar
Frece, J, Kos, B, Svetec, IK, Zgaga, Z, Beganović, J, Leboš, A & Šušković, 2009 Synbiotic effect of Lactobacillus helveticus M92 and prebiotics on the intestinal microflora and immune system of mice. Journal of Dairy Research 76 98–104CrossRefGoogle ScholarPubMed
Gasanov, U, Hughes, D & Hansbro, PM 2005 Methods for the isolation and identification of Listeria spp. and Listeria monocytogenes: a review. FEMS Microbiology Reviews 29 851–875Google Scholar
Gilot, P & Content, J 2002 Specific identification of Listeria welshimeri and Listeria monocytogenes by PCR assays targeting a gene encoding a fibronectin-binding protein. Journal of Clinical Microbiology 40 698–703CrossRefGoogle ScholarPubMed
Gouws, PA & Liedemann, I 2005 Evaluation of Diagnostic PCR for the detection of Listeria monocytogenes in food products. Food Technology and Biotechnology 43(2) 201–205Google Scholar
Grady, JO, Sedano-Balbas, S, Maher, M, Smith, T & Barry, T 2008 Rapid real-time PCR detection of Listeria monocytogenes in enriched food samples based on the ssrA gene, a novel diagnostic target. Food Microbiology 25 (1) 75–84CrossRefGoogle Scholar
Harvey, J, Keenan, KP & Gilmour, A 2007 Assesing biofilm formation by Listeria monocytogenes strains. Food Microbiology 24 (4) 380–392CrossRefGoogle Scholar
Liu, D 2006 Identification, subtyping and virulence determination of Listeria monocytogenes, an important foodborne pathogen. Journal of Medical Microbiology 55 (part 6) 645–659Google Scholar
Markov, K, Frece, J, Čvek, D & Delaš, F 2009 Microbiological analysis of fresh cheese and cream produced domestically from unpasterised milk in the city of Zagreb with attention on bacteria Listeria monocytogenes. Mljekarstvo 59 (3) 225–231Google Scholar
McLauchin, J 1997 The identification of Listeria species. International Journal of Food Microbiology 38 77–81Google Scholar
Oravcova, K, Trnčikova, T, Kuchta, T & Kaclikova, E 2008 Limitation in the detection of Listeria monocytogenes in food in the presence of competing Listeria innocua. Journal of Applied Microbiology 104 429–437Google Scholar
Pozaić, S 2008 Identification of different strains of Listeria spp. in foods and environment using conventional methods and PCR method, Master Thesis, Faculty of Food Technology and Biotechnology, University of Zagreb, CroatiaGoogle Scholar
Rodriguez-Lazaro, D, Hernandez, M, Scortti, M, Esteve, T, Vasquez-Boland, JA & Pla, M 2004a Quantitative detection of Listeria monocytogenes and Listeria innocua by real-time PCR; assessment of hly, iap and lin02483 targets and AmpliFlour technology. Applied Environmental Microbiology 70 1366–1377Google Scholar
Rodriguez-Lazaro, D, Hernandez, M & Pla, M 2004b Simultaneous quantitative detection of Listeria spp. and Listeria monocytogenes using a duplex real time PCR-based assay. FEMS Microbiology Letter 233 257–267CrossRefGoogle ScholarPubMed
Vanegas, MC, Vasquez, E, Martinez, AJ & Rueda, AM 2009 Detection of Listeria monocytogenes in raw whole milk for human consumption in Columbia by real-time PCR. Food Control 20 430–432Google Scholar
Vaz-Velho, M, Duarte, G & Gibbs, P 2001 Evaluation of enhanced haemolysis agar for detection of Listeria spp. and Listeria monocytogenes from production lines of fresh to cold-smoked fish. Journal of Microbiological Methods 46 157–163Google Scholar