The isolation and detection of Listeria monocytogenes in various foods by use of immunomagnetic capture

Ozbas Z.

ARCHIV FUR LEBENSMITTELHYGIENE, vol.53, no.4, pp.79-82, 2002 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 53 Issue: 4
  • Publication Date: 2002
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.79-82
  • Hacettepe University Affiliated: No


Listeria monocytogenes is a pathogenic bacterium responsible for severe foodborne infections worldwide. The epidemics caused by food contaminated with L. monocytogenes have recently become the subject of renewed interest. Standard methods of Listeria detection are laborious and time-consuming, requiring many steps for taking results. The use of immunomagetic separation (IMS) has been suggested as a method of reducing total analysis time and improving sensitivity of detection. In this study IMS has been used for detection of L. monocytogenes in a model system, spiked and naturally contaminated foods, in parallel with the traditional cultural methods, as a reference method. Methods have been compared in terms of specificity, sensitivity and recovery of the pathogen. IMS with immunomagnetic beads (Dynabeads(R) anti-Listeria) was used for the recovery and isolation of the pathogen. This study demonstrated the ability of IMS and commercially available beads, to enable the recovery of spiked L. monocytogenes from various foods, in a similar sensitivity as with the conventional method. Specificity studies of IMS showed that all tested Listeria strains scored as positive. To evaluate accuracy, a comparative study was performed with 46 food samples for isolating the pathogen. While 14 samples were found as positive by both methods, 32 foods scored as negative. Statistical analysis indicated that there were no significant differences (P > 0.05) between the two methods. IMS seems to be a simpler and more efficient method for capturing L. monocytogenes from foods as compared to the conventional method.