Detection of Viable Listeria monocytogenes in Dairy Products By Real Time Reverse-Transcription PCR

Listeria monocytogenes is a food-borne pathogen which can cause zoonosis. A detection method based on real time reverse-transcription PCR amplification of mRNA was established in the study. This method can overcome false-positive result caused by amplification of nonviable L.monocytogenes. Sensitivity and specificity of the method were studied, as well as artificially contaminated dairy products by L.monocytogenes, dairy products from market and L.monocytogenes biofilm. For contaminated milk, detection sensitivity was 17CFU/ml after 6h enrichment. Detection limit in biofilm was 2×10 2 CFU/cm 2 after 7h enrichment. The results indicate that the method can satisfy detection of L.monocytogenes in dairy products and biofilm. Key words-real time RT-PCR; Listeria monocytogenes; biofilm

[1]  P. de Coppet,et al.  Quantitative Detection of Listeria monocytogenes in Biofilms by Real-Time PCR , 2005, Applied and Environmental Microbiology.

[2]  G. Pugliese,et al.  Biofilms: Survival Mechanisms of Clinically Relevant Microorganisms , 2002, Infection Control & Hospital Epidemiology.

[3]  V. Juneja,et al.  Sensitive detection of viable Listeria monocytogenes by reverse transcription-PCR , 1997, Applied and environmental microbiology.