Quantification of Salmonella spp., Listeria monocytogenes and Escherichia coli O157:H7 in non-spiked food products and evaluation of real-time PCR as a diagnostic tool in routine food analysis

Elizaquível, Patricia; Gabaldón, José Antonio; Aznar, Rosa

doi:10.1016/j.foodcont.2010.05.018

Cited by 42 publications

(26 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Among molecular-based methods, PCR has been established as a valuable alternative to the traditional detection methods and oVers the possibility of detecting speciWc genes involved in pathogen virulence. In recent years, PCR procedures have demonstrated to be suitable for the pathogen detection in food products, because they are rapid and simple to use [37]. Multiplex PCR allows the simultaneous ampliWcation of more than one target sequence in a single PCR, saving considerable time and eVort and decreasing the number of reactions to be performed in order to assess the possible presence of foodborne pathogens in a food sample [29].…”

Section: Discussionmentioning

confidence: 99%

“…Advances in molecular biology have led to the use of real-time PCR as an eYcient and reproducible method for detecting pathogens [38]; moreover, real-time PCR allows accurate, automated and quantitative detection of diVerent microorganisms without the need to open the tubes for electrophoresis after ampliWcation, thus reducing the risk of cross-contamination [37].…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Development of a multiplex real-time PCR method for simultaneous detection of Salmonella enterica, Shigella flexneri and Listeria monocytogenes in processed food samples

Garrido

Chapela

Román

et al. 2012

Eur Food Res Technol

View full text Add to dashboard Cite

The present work is focused on the development of a TaqMan multiplex real-time PCR method for the detection of Salmonella, Shigella and L. monocytogenes in seafood, meat and ready-to-eat products. The aim of this study is to detect the three pathogens in one single test including an enrichment medium for the simultaneous growth of the bacteria of interest and an Internal AmpliWcation Control (IAC) to monitor PCR inhibitors. For this purpose, three genes were selected, invA for Salmonella, ipaH for Shigella and hlyA for L. monocytogenes. Also, no. 17 broth without dextrose and further modiWed by adding Tween 80 was used for the enrichment step. SpeciWcity of the method was checked against a panel of 24 non-target bacterial strains. RT-PCR eYciency obtained for the simultaneous ampliWcation of all three pathogens was 102.5% for Salmonella, 108.9% for Shigella and 106.4% for L. monocytogenes. The limit of detection (LOD) was evaluated in seafood, meat and ready-to-eat products, being established within 3 and 22 cfu in 25 g of sample for the three bacteria analyzed. Seventy-eight samples were analyzed with multiplex RT-PCR including spiked and natural samples collected from diVerent laboratories. Even though several RT-PCR methods have been developed for the detection of Salmonella, Shigella and L. monocytogenes, as far as we know this is the Wrst method developed for the simultaneous detection of these three pathogens, coupling RT-PCR with an enrichment in the same broth and being tested in a wide range of diVerent processed food samples with a low LOD. The application of this method can signiWcantly reduce costs and time of analysis in laboratories, what would be reXected in a faster response in those risk situations when they are detected.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Development of a multiplex real-time PCR method for simultaneous detection of Salmonella enterica, Shigella flexneri and Listeria monocytogenes in processed food samples

Garrido

Chapela

Román

et al. 2012

Eur Food Res Technol

View full text Add to dashboard Cite

show abstract

“…Multiplex PCR improved the diagnosis, allowing the investigation of different virulence factors in the same reaction (Francis 2004), speeding results and reducing genotyping costs (Ruiz-Rueda et al 2011). Real-time polymerase chain reaction (qPCR) generate results in higher speed, sensitivity and specificity when compared to traditional PCR methods (Elizaquivel et al 2010). The objective of this study was to investigate the ETEC virotypes associated with post--weaning diarrhea in pig farms from Southern Brazil, using a multiplex qPCR protocol.…”

Section: Introductionmentioning

confidence: 99%

Virulence profiles of enterotoxigenic Escherichia coli isolated from piglets with post-weaning diarrhea and classification according to fecal consistency

et al. 2016

View full text Add to dashboard Cite

The aim of this study was to assess the frequency and association of virulence factors of Escherichia (E.) coli isolated from weaned piglets with diarrhea and to correlate it with fecal consistency. A total of 152 rectal swabs were collected from 25-40 day-old piglets with diarrhea, in farms of Southern Brazil. Phenotypical and molecular techniques were used for bacterial isolation, characterization and classification of enterotoxigenic E. coli (ETEC) pathotypes. Statistical analysis was carried out to determine the frequency of virulence factors and virotypes, of fimbriae F4, F5, F6, F18, F41 and toxins LT, STa, STb and STx2e. Out of 456 E. coli isolates, 287 (62.9%) samples showed significant growth of E. coli. Among them, 194 (67.6%) samples showed at least one virulence factor, indicating that ETEC is an important etiological agent of diarrhea in weaned piglets. Higher frequencies were found of fimbria F4 and F18 and enterotoxins LT, STa and STb. Significant association was found to F4, LT, STa and STb; between F18 and STa and STx2e; between F5 and LT, STa and STb. The most frequent virotypes were F18-STa, F4-LT-STa-STb, F4-STa, F4-LT-STb and F18-STa-STx2e. Beta-hemolysis was observed in 47.4% of samples and there was significant association between hemolytic samples and virulence factors F4, F18, STa and STx2e. Regarding fecal consistency, there was significant association of liquid feces and F4 fimbria, STa toxin and virotypes F4-STa and F4-F5-LT-STa-STb. Since there was significant association of ETEC and liquid feces in nursery piglets, it is important to prioritize the sampling of liquid feces for the diagnosis etiologic cause of diarrhea.

show abstract

“…In recent years, qPCR has been a popular tool for identifying and quantifying E. coli O157:H7 because of its sensitivity, specificity and time-efficiency (Elizaquível, Gabaldón, & Aznar, 2011;Elizaquível, Sánchez, Selma, & Aznar, 2012;Shannon, Lee, Trevors, & Beaudette, 2007). In this study, an SD-PMA-qPCR assay with primers targeting the flic DNA was successfully applied to detect and quantify viable E. coli O157:H7 in spiked milk matrix.…”

Section: Discussionmentioning

confidence: 99%

Rapid and accurate detection of viable Escherichia coli O157:H7 in milk using a combined IMS, sodium deoxycholate, PMA and real-time quantitative PCR process

Li-jun

Zhang

et al. 2014

Food Control

View full text Add to dashboard Cite

Quantification of Salmonella spp., Listeria monocytogenes and Escherichia coli O157:H7 in non-spiked food products and evaluation of real-time PCR as a diagnostic tool in routine food analysis

Cited by 42 publications

References 31 publications

Development of a multiplex real-time PCR method for simultaneous detection of Salmonella enterica, Shigella flexneri and Listeria monocytogenes in processed food samples

Development of a multiplex real-time PCR method for simultaneous detection of Salmonella enterica, Shigella flexneri and Listeria monocytogenes in processed food samples

Virulence profiles of enterotoxigenic Escherichia coli isolated from piglets with post-weaning diarrhea and classification according to fecal consistency

Rapid and accurate detection of viable Escherichia coli O157:H7 in milk using a combined IMS, sodium deoxycholate, PMA and real-time quantitative PCR process

Contact Info

Product

Resources

About