Mafu A A, Pitre M, Sirois S
Food Research and Development Centre, Agriculture and Agri-Food Canada, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec, Canada J2S 8E3.
J Food Prot. 2009 Jun;72(6):1310-4. doi: 10.4315/0362-028x-72.6.1310.
Foodborne pathogens such as Escherichia coli O157:H7, Listeria monocytogenes, and Salmonella can easily transfer from food to food contact surfaces. Methods for rapid detection of these pathogenic bacteria are important in order to avoid contamination of food. Here, we describe the detection and quantification of bacterial pathogens on contaminated surfaces by real-time PCR (RT-PCR) and culture methods using a single enrichment medium. Surfaces of wood, polypropylene, and stainless steel were inoculated with a mixed culture of E. coli O157:H7, L. monocytogenes, and S. enterica. Surfaces were sampled after an initial contact time of 10 min and after 16 h. Results indicated that after a short contact time, RT-PCR gave results similar to standard microbiological counts for each pathogen tested. However, after being left for 16 h on surfaces, the detection of these pathogens at low inoculation levels was always possible with RT-PCR, while microbiological methods failed to detect them in many cases. In conclusion, RT-PCR is more sensitive and rapid than are standard microbiological methods for the detection of bacterial pathogens on food contact surfaces.
食源性病原体，如大肠杆菌O157:H7、单核细胞增生李斯特菌和沙门氏菌，很容易从食物转移到食品接触表面。为避免食物污染，快速检测这些病原菌的方法至关重要。在此，我们描述了使用单一富集培养基，通过实时PCR（RT-PCR）和培养方法对污染表面的细菌病原体进行检测和定量。用大肠杆菌O157:H7、单核细胞增生李斯特菌和肠炎沙门氏菌的混合培养物接种木材、聚丙烯和不锈钢表面。在初始接触10分钟后和16小时后对表面进行采样。结果表明，在短接触时间后，RT-PCR给出的结果与每种测试病原体的标准微生物计数结果相似。然而，在表面放置16小时后，RT-PCR总能检测到低接种水平的这些病原体，而微生物学方法在许多情况下未能检测到它们。总之，在检测食品接触表面的细菌病原体方面，RT-PCR比标准微生物学方法更灵敏、更快速。
