Open AccessImproved sample treatment protocol for accurate detection of live Salmonella spp. in food samples by viability PCR
Author(s) -
Mai Dinh Thanh,
Gemma Agustí,
Anneluise Mader,
Bernd Appel,
Francesc Codony
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0189302
Subject(s) - salmonella , protocol (science) , sample (material) , contamination , biology , microbiology and biotechnology , computational biology , food science , biochemical engineering , chromatography , chemistry , medicine , genetics , bacteria , ecology , alternative medicine , pathology , engineering
Culture-based detection is still considered as the standard way for detection of Salmonella in foods, although molecular methods, such as viability PCR (vPCR), have been introduced to overcome some disadvantages of traditional culture methods. Despite the success of the vPCR methodology, the problem of false-positive results is a major drawback, especially when applied to environmental samples, hindering the interpretation of the results. To improve the efficiency of vPCR, many approaches have been introduced by several authors during the last years. In the present work, the combination of PEMAX dye, double tube change, and double photo-activation step was established as a strategy to improve vPCR protocol. By combining these approaches, we developed an improved sample treatment protocol able to neutralize DNA signals of up to 5.0×10 7 dead cells/sample from both pure culture and artificially contaminated food samples. Our results indicate that vPCR can work reliable and has a potential for high throughput detection of live Salmonella cells in food samples, minimizing false-positive signals.