Please use this identifier to cite or link to this item: http://hdl.handle.net/1822/24326

TitleDetection of Salmonella enterica serovar Enteritidis using real time PCR, immunocapture assay, PNA FISH and standard culture methods in different types of food samples
Author(s)Almeida, Carina
Cerqueira, L.
Azevedo, N. F.
Vieira, M. J.
KeywordsSalmonella
Detection
PNA FISH
Real time PCR
Immunoassay
Issue date2013
PublisherElsevier
JournalInternational Journal of Food Microbiology
Abstract(s)Several methods for the rapid and specific detection of Salmonella in food samples have been described. Here, we compare 4 of those methods in terms of assay time, procedure complexity, detection limit, sensitivity, specificity and accuracy. Milk, eggs and mayonnaise samples were artificially contaminated with Salmonella enterica serovar Enteritidis cell concentrations ranging from 1 × 10- 2 to 1 × 102 CFU per 25 g or ml of food. Samples were then pre-enriched and analyzed by either: i) real-time PCR, using the iQ-Check Salmonella kit; ii) immunocapture, using the RapidChek SELECT Salmonella; iii) a peptide nucleic acid fluorescence in situ hybridization (PNA FISH) method and iv) the traditional bacteriological method ISO 6579:2002. All methods were able to detect Salmonella in the different types of food matrixes and presented a similar detection level of 1 CFU per 25 g or ml of food sample. The immunocapture and the PNA FISH methods proved to be very reliable, as their results were 100% in agreement with the ISO method. However, real-time PCR presented a significant number of false positives, which resulted in a specificity of 55.6% (CI 95%, 31.3 – 77.6) and an accuracy of 82.2%(CI 95%, 63.2 – 91.4) for this method. Sensitivity was 100% since no false negative results were observed. In conclusion, the implementation of these molecular techniques, mainly the immunocapture and PNA-FISH methods, provides a reliable and less time-consuming alternative for the detection of Salmonella spp. in food samples.
TypeArticle
URIhttp://hdl.handle.net/1822/24326
DOI10.1016/j.ijfoodmicro.2012.11.014
ISSN0168-1605
Publisher versionwww.elsevier.com/locate/ijfoodmicro
Peer-Reviewedyes
AccessOpen access
Appears in Collections:CEB - Publicações em Revistas/Séries Internacionais / Publications in International Journals/Series

Files in This Item:
File Description SizeFormat 
1-s2.0-S0168160512006034-main.pdf760,37 kBAdobe PDFView/Open

Partilhe no FacebookPartilhe no TwitterPartilhe no DeliciousPartilhe no LinkedInPartilhe no DiggAdicionar ao Google BookmarksPartilhe no MySpacePartilhe no Orkut
Exporte no formato BibTex mendeley Exporte no formato Endnote Adicione ao seu ORCID