소시지에서 real-time PCR법에 의한 Listeria monocytogenes의 정량적 검출을 위한 standard curve구축

Construction of standard curve for quantitative detection of Listeria monocytogenes in ready-to-eat sausages by real-time PCR method

We constructed a standard curve to quantify Listeria monocytogenes in ready-to-eat product, especially sausage samples, using real-time PCR. A standard curve was generated using serially diluted L. monocytogenes cells in distilled water. When cells were artificially inoculated in 10 g of sausage samples in 90㎖buffered peptone water, the cell concentration of range was approximately 1.0×108 to 100 CFU/㎖. The standard curve of the serially diluted cells was linear for at least seven orders of magnitude from 103 to 109 CFU/㎖of L. monocytogenes. When cells were diluted in sausages, the linearity range was from 104 to 108 CFU/㎖. The correlation coefficient (R2) of diluted cells was 0.9888 and the slope of the curve was -2.6621. The coefficient and slope of inoculated samples were 0.9916 and -2.747, respectively. The R2 value for serially diluted L. monocytogenes and artificially contaminated sausage samples were acceptable. The approach described in this study represents the potency of the quantification of L. monocytogenes in sausage samples by quantitative real-time PCR. It can be used in monitoring the presence and persistence of this pathogen in sausages.