Ningbo University, Ningbo, 315211, China.
Ningbo Institute of Oceanography, Ningbo, 315832, China.
Bioprocess Biosyst Eng. 2018 May;41(5):603-611. doi: 10.1007/s00449-018-1895-2. Epub 2018 Jan 18.
Salmonella is a major pathogen that causes acute foodborne outbreaks worldwide. Seafood, particularly shellfish, is a proven source of Salmonella spp. infection because many people prefer to eat it raw or lightly cooked. However, traditional identification methods are too time-consuming and complex to detect contamination of bacteria in the food chain in a timely manner, and few studies have aimed to identify Salmonella in shellfish early in the supply chain. We herein developed a method for rapid detection of Salmonella in shellfish based on the method of recombinase polymerase amplification (RPA) combined with lateral flow dipstick (LFD), which targets the invasion gene A (invA). The RPA-LFD was able to function at 30-45 °C, and at the temperature of 40 °C, it only took 8 min of amplification to reach the test threshold of amplicons. The established method had both a good specificity and a sensitivity of 100 fg DNA per reaction (20 µL). Regarding practical performance, RPA-LFD performed better than real-time PCR. Another advantage of RPA-LFD is that it was capable of being performed without expensive equipments. Thus, RPA-LFD has potential for further development as a detection kit for Salmonella in shellfish and other foods under field conditions.
沙门氏菌是一种主要的病原体，可导致全球范围内的急性食源性疾病爆发。海鲜，特别是贝类，是已证实的沙门氏菌属感染源，因为许多人喜欢生吃或轻度烹饪。然而，传统的鉴定方法过于耗时且复杂，无法及时检测食物链中的细菌污染，而且很少有研究旨在早期供应链中鉴定贝类中的沙门氏菌。本研究基于重组酶聚合酶扩增（RPA）与横向流动试纸条（LFD）相结合的方法，针对侵袭基因 A（invA），开发了一种用于贝类中沙门氏菌快速检测的方法。RPA-LFD 可在 30-45°C 下运行，在 40°C 时，仅需 8 分钟的扩增即可达到扩增子的测试阈值。该方法具有良好的特异性和灵敏度，每个反应（20µL）的 DNA 灵敏度为 100 fg。关于实际性能，RPA-LFD 比实时 PCR 表现更好。RPA-LFD 的另一个优点是它能够在没有昂贵设备的情况下进行。因此，RPA-LFD 有可能进一步开发成为在现场条件下用于贝类和其他食品中沙门氏菌的检测试剂盒。
