3M Company, Food Safety Department, St. Paul, MN 55144-1000, USA.
Q Laboratories, Microbiology Research and Development Laboratory, Cincinnati, OH 45204, USA.
J AOAC Int. 2022 Jun 29;105(4):1126-1135. doi: 10.1093/jaoacint/qsac014.
The 3M™ Molecular Detection Assay 2 - STEC Gene Screen (stx) method is based on gene amplification by the use of real-time loop-mediated isothermal amplification when used with the 3M Molecular Detection System for the rapid and specific detection of Shiga toxin gene (stx1 and/or stx2) from Shiga toxin-producing enterohemorrhagic Escherichia coli (STEC) in enriched foods.
The 3M Molecular Detection Assay 2 - STEC Gene Screen (stx) method was evaluated as a Level 2 method modification to add new matrixes to the certified claim: 25 g fresh raw ground beef (approximately 75% lean), 375 g raw beef trim (approximately 75% lean), 375 g fresh raw ground pork (approximately 70% lean), 375 g fresh raw poultry parts, and 25 g sprouts.
Matrix studies were conducted to assess the method's performance compared to the US Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Guidebook, 5C.00 for meat and poultry, and to the US Food and Drug Administration Bacteriological Analytical Manual, Ch. 4A for sprouts, using an unpaired study design.
The 3M Molecular Detection Assay 2 - STEC Gene Screen (stx) method demonstrated no significant differences between presumptive and confirmed results or between candidate and reference method results for any of the matrices tested.
The data collected in these studies demonstrate that the 3M Molecular Detection Assay 2 - STEC Gene Screen (stx) is a reliable method for the rapid and specific detection of STEC in fresh raw ground beef (approximately 75% lean), fresh raw beef trim (approximately 75% lean), fresh raw ground pork (approximately 70% lean), fresh raw poultry parts, and sprouts.
3M™ Molecular Detection Assay 2-STEC Gene Screen(stx)方法基于实时环介导等温扩增基因扩增，与 3M Molecular Detection System 一起使用，可快速、特异性检测产志贺毒素的肠出血性大肠杆菌(STEC)中的志贺毒素基因(stx1 和/或 stx2)。
3M Molecular Detection Assay 2-STEC Gene Screen(stx)方法被评估为二级方法修改，为已认证的声明添加新基质：25g 新鲜生绞碎牛肉(约 75%瘦肉)、375g 生牛肉切块(约 75%瘦肉)、375g 新鲜生绞碎猪肉(约 70%瘦肉)、375g 新鲜生禽肉和 25g 芽菜。
采用非配对研究设计，对基质进行研究，评估该方法与美国农业部食品安全检验局微生物实验室指南 5C.00 相比在肉类和家禽方面，以及与美国食品和药物管理局细菌分析手册 Ch.4A 相比在芽菜方面的性能。
3M Molecular Detection Assay 2-STEC Gene Screen(stx)方法对任何测试基质的推定和确认结果之间，候选和参考方法之间，均无显著差异。
这些研究中收集的数据表明，3M Molecular Detection Assay 2-STEC Gene Screen(stx)是一种可靠的方法，可快速、特异性地检测新鲜生绞碎牛肉(约 75%瘦肉)、新鲜生牛肉切块(约 75%瘦肉)、新鲜生绞碎猪肉(约 70%瘦肉)、新鲜生禽肉和芽菜中的 STEC。
