Applied Food Diagnostics, Inc., 18 Industrial Drive, Bloomsburg, PA 17815, USA.
J AOAC Int. 2021 Sep 27;104(5):1355-1365. doi: 10.1093/jaoacint/qsab034.
The Molecular Environmental Monitoring Program (MEMP) Listeria Assay is a quick, reliable method for detecting Listeria species in environmental samples. The assay incorporates a real-time PCR approach to identifying Listeria cells expressed from the swab sample. The assay does not require an enrichment step, leading to much faster time to a negative result.
This report details the method validation study to validate the MEMP using environmental surface swabs for stainless steel, plastic, rubber, ceramic tile, and sealed concrete.
Matrix studies, inclusivity/exclusivity, product consistency and stability, and robustness testing were conducted to assess the method's performance. In the matrix studies, this method was compared to the US Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM) Chapter 10 for environmental surface sponges and swabs.
Inclusivity and exclusivity testing showed that the MEMP Listeria Assay was able to detect all 75 Listeria strains tested while excluding the 30 non-Listeria species. There were no statistically significant differences found between the candidate and reference methods. Small variations in critical test parameters (volume of extraction reagent and volume of extracted DNA sample) did not adversely affect the assay's performance, and stability testing indicated consistent results for at least 1 year.
The data presented in this report show that the candidate method performed as well as the reference method and can therefore be used in place of the reference method for detecting Listeria species.
The MEMP Listeria Assay requires no enrichment for detecting Listeria on environmental surfaces.
分子环境监测计划（MEMP）李斯特菌检测是一种快速、可靠的方法，可用于检测环境样本中的李斯特菌属。该检测采用实时 PCR 方法来识别拭子样本中表达的李斯特菌细胞。该检测不需要富集步骤，从而大大缩短了获得阴性结果的时间。
本报告详细介绍了使用环境表面拭子（包括不锈钢、塑料、橡胶、瓷砖和密封混凝土）对 MEMP 进行验证的方法验证研究。
进行了基质研究、包容性/排他性、产品一致性和稳定性以及稳健性测试，以评估该方法的性能。在基质研究中，该方法与美国食品和药物管理局（FDA）的《细菌分析手册》（BAM）第 10 章中用于环境表面海绵和拭子的方法进行了比较。
包容性和排他性测试表明，MEMP 李斯特菌检测能够检测到所有 75 株李斯特菌菌株，同时排除了 30 种非李斯特菌属。候选方法和参考方法之间没有发现统计学上的显著差异。关键测试参数（提取试剂的体积和提取的 DNA 样品的体积）的微小变化不会对检测结果产生不利影响，稳定性测试表明至少在 1 年内结果一致。
本报告中提供的数据表明，候选方法的性能与参考方法相当，因此可以替代参考方法用于检测李斯特菌属。
MEMP 李斯特菌检测无需富集即可检测环境表面的李斯特菌。
