Detection of viable but non-culturable Escherichia coli O157:H7 by PCR in combination with propidium monoazide.

ABSTRACT: The aim of this study was to evaluate the applicability of the conventional PCR detection method combined with propidium monoazide (PMA) treatment for the detection of viable but non-culturable (VBNC) state Escherichia coli O157:H7 in ground beef meatballs. Under low temperature, E. coli O157:H7 cells were induced into the VBNC state in ground beef meatballs at - 20 °C after 152 days. The optimal PMA concentration of 5 µg/mL was obtained in beef meatball samples, which could completely inhibit the DNA amplification on dead cells (106 cells/mL) but with no inhibition on viable cells. The established PMA-PCR assay revealed that the VBNC counts exceeded 107 CFU/mL in artificial contamination beef samples, which could be used for semi-quantitative detection of VBNC cells in beef meatball sampl

SUBMITTER: Zhong J 

PROVIDER: S-EPMC5740038 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature