School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, 230009, China.
J Food Sci. 2012 Nov;77(11):M616-9. doi: 10.1111/j.1750-3841.2012.02951.x. Epub 2012 Oct 11.
Cronobacter are opportunistic food-borne pathogens associated with meningitis, sepsis, and necrotizing enterocolitis. Little attempt has focused on detection of viable cell of Cronobacter spp. in dry aquatic products, which were frequently used for raw materials of infant foods due to high nutrition. In this paper, one-step reverse transcription polymerase chain reaction (RT-PCR) was developed for detection of viable Cronobacter spp. in dry aquatic products. Specificity test indicated that clearly expected amplicon in size 469 bp was amplified from RNA of Cronobacter, but not from RNA of negative controls and DNA of Cronobacter strains. The sensitivity was 10(4) CFU/mL of Cronobacter strain in artificially fish meal samples and 10(1) CFU/mL of Cronobacter after 10-h enrichment. In a total of 81 dry aquatic products, 9.8%, 8.6%, and 9.8% of samples were found to be positive for Cronobacter by one-step RT-PCR, U.S. Food and Drug Administration method, and Druggan-Forsythe-Iversen medium, respectively. The results clearly indicated that one-step RT-PCR could avoid the interference of residual DNA of Cronobacter in food samples and be used to specifically detect viable Cronobacter spp. for large-scale monitoring of food samples.
The use of rapid and specific detection of food borne pathogens in food samples was most of importance for control and precaution of food borne diseases. In this study, one-step RT-PCR was developed for detection of Cronobacter spp. in aquatic products. A comparison of different methods for detection of Cronobacter indicated that the newly developed method could be widely used to specifically detect Cronobacter spp. in food samples.
克罗诺杆菌是一种机会性食源性病原体，与脑膜炎、败血症和坏死性小肠结肠炎有关。目前很少有研究关注于检测干燥水产品中存活的克罗诺杆菌细胞，这些细胞由于高营养价值而经常被用作婴儿食品的原料。在本文中，开发了一种一步法逆转录聚合酶链反应（RT-PCR）来检测干燥水产品中的存活的克罗诺杆菌。特异性试验表明，在大小为 469 bp 的预期扩增子从克罗诺杆菌的 RNA 中扩增，但从阴性对照的 RNA 和克罗诺杆菌株的 DNA 中没有扩增。在人工鱼粉样品中，克罗诺杆菌株的灵敏度为 10（4）CFU/mL，10 小时富集后为 10（1）CFU/mL。在总共 81 份干燥水产品中，一步法 RT-PCR、美国食品和药物管理局方法和 Druggan-Forsythe-Iversen 培养基分别检测到克罗诺杆菌阳性的样品占 9.8%、8.6%和 9.8%。结果表明，一步法 RT-PCR 可以避免食品样品中克罗诺杆菌残留 DNA 的干扰，并且可用于特异性检测存活的克罗诺杆菌，以便对食品样品进行大规模监测。
快速、特异性地检测食品样品中的食源性病原体对于控制和预防食源性疾病至关重要。本研究开发了一种用于检测水产品中克罗诺杆菌的一步法 RT-PCR。不同方法检测克罗诺杆菌的比较表明，新开发的方法可广泛用于特异性检测食品样品中的克罗诺杆菌。
