多实验室验证研究实时 PCR 方法检测婴儿菠菜中的沙门氏菌。

Multi-laboratory validation study of a real-time PCR method for detection of Salmonella in baby spinach.

机构信息

FDA-Center for Food Safety and Applied Nutrition (CFSAN), 6502 S. Archer Rd, Bedford Park, IL, 60501, USA.

FDA-Center for Food Safety and Applied Nutrition (CFSAN), 5001 Campus Dr, College Park, MD 20740, USA.

出版信息

Food Microbiol. 2023 Sep;114:104299. doi: 10.1016/j.fm.2023.104299. Epub 2023 May 5.

DOI:10.1016/j.fm.2023.104299

PMID:37290875

Abstract

The FDA Bacteriological Analytical Manual (BAM) Salmonella culture method takes at least 3 days for a presumptive positive result. The FDA developed a quantitative PCR (qPCR) method to detect Salmonella from 24-h preenriched cultures, using ABI 7500 PCR system. The qPCR method has been evaluated as a rapid screening method for a broad range of foods by single laboratory validation (SLV) studies. The present multi-laboratory validation (MLV) study was aimed to measure the reproducibility of this qPCR method and compare its performance with the culture method. Sixteen laboratories participated in two rounds of MLV study to analyze twenty-four blind-coded baby spinach test portions each. The first round yielded ∼84% and ∼82% positive rates across laboratories for the qPCR and culture methods, respectively, which were both outside the fractional range (25%-75%) required for fractionally inoculated test portions by the FDA's Microbiological Method Validation Guidelines. The second round yielded ∼68% and ∼67% positive rates. The relative level of detection (RLOD) for the second-round study was 0.969, suggesting that qPCR and culture methods had similar sensitivity (p > 0.05). The study demonstrated that the qPCR yields reproducible results and is sufficiently sensitive and specific for the detection of Salmonella in food.

摘要

美国食品药品监督管理局（FDA）的细菌学分析手册（BAM）沙门氏菌培养方法得出阳性结果至少需要 3 天。FDA 开发了一种定量 PCR（qPCR）方法，用于从 24 小时预富集培养物中检测沙门氏菌，使用 ABI 7500 PCR 系统。该 qPCR 方法已通过单一实验室验证（SLV）研究被评估为一种用于广泛食品的快速筛选方法。本多实验室验证（MLV）研究旨在衡量该 qPCR 方法的重现性，并将其性能与培养方法进行比较。16 个实验室参加了两轮 MLV 研究，每个实验室分析了 24 个盲样婴儿菠菜测试部分。第一轮的 qPCR 和培养方法的阳性率分别约为 84%和 82%，均超出 FDA 微生物方法验证指南规定的用于部分接种测试部分的分数范围（25%-75%）。第二轮的阳性率约为 68%和 67%。第二轮研究的相对检测水平（RLOD）为 0.969，表明 qPCR 和培养方法具有相似的灵敏度（p>0.05）。该研究表明，qPCR 可产生可重复的结果，并且对食品中沙门氏菌的检测具有足够的灵敏度和特异性。