Evaluation of the MALDI-TOF-MS for the detection of Listeria monocytogenes in Ready-to-Eat Food Products

项目名称 基质辅助激光解吸电离飞行时间质谱的评价 （MALDI-TOF-MS）检测入口即食食品中的单核细胞增生李斯特菌 摘要 目的：本提案将评估使用MALDI-TOF-MS系统检测L。中单核细胞增生 高风险食品（HRF），如即食（RTE）进口食品，可以生吃（例如， 腌鱼、熟食肉类）或重新加热（如法兰克福香肠）或生吃（水果、蔬菜如豆芽）。 L.单核细胞增多症有能力在冷藏或冰箱温度下生长， 进口或本地制造的产品（奶酪、熟食、腌鱼、熟食 甲壳类动物等）都储存起来了（三） 方法：采用MALDI-TOF-MS技术对L.单核细胞增生直接从一个选择性的 培养30小时的增菌肉汤，以使微生物生长和繁殖 其数量无需在平板培养基上培养和分离即可检测到。我们将 证明MALDI-TOF-MS系统鉴定L.激光解吸法 电离的样品附着到矩阵晶体。这个过程产生了一个独特的质谱 可用于与MALDI-TOF-MS系统中的参考库进行比较的模式或指纹 数据库来识别微生物。(4)（五）（六） 本研究的意义和影响：建立一种快速检测L.单核 由于其能够在冷藏或冰箱温度下生长，其中RTE食品， 进口或本地制造的都储存起来。(3)HRF对即食食品的认定基于几个因素 如食品安全现代化法案（FSMA）第204（d）（2）（A）条所定义。(1)快速 检测L.从受污染的即食进口食品中提取单核细胞增多症是预防 分发受乳酸杆菌污染的即食食物/食品。单核细胞增多症， 在储存时不断增殖/多层。

Project Title Evaluation of the Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) for the detection of Listeria monocytogenes in Ready-To-Eat Imported Food Products Abstract Aim: This proposal will evaluate the use of the MALDI-TOF-MS system to detect L. monocytogenes in high-risk foods (HRFs) such as Ready-to-Eat (RTE) imported foods that may be eaten uncooked (e.g., preserved fish, deli meats) or re-heated ( e.g. frankfurters) or eaten raw ( fruits, vegetables like sprouts). L. monocytogenes has the ability to grow in cold storage or refrigerator temperature where RTE food products, imported or locally made (cheese, deli meats, preserved fish, cooked-ready-to-eat crustaceans, etc.) are stored. (3) Method: MALDI-TOF-MS technology will be used to identify L. monocytogenes directly from a selective enrichment broth that has been incubated for 30 hours to allow the organism to grow and multiply in numbers that can be detected without culture and isolation on a plated media. We will demonstrate that the MALDI-TOF-MS system identifies L. monocytogenes through laser desorption ionization of the sample attached to a matrix crystals. This process generates a unique mass spectral pattern or fingerprint that can be used to compare with reference libraries in the MALDI-TOF-MS system database to identify the microorganism. (4) (5) (6) Significance and Impact of the Study: It is critical to have a rapid method to detect L. monocytogenes because of its ability to grow in cold storage or refrigerator temperature where RTE food products, imported or locally made are stored. (3) The HRF designation of RTE foods is based on several factors as defined in Section 204 (d) (2) (A) of the Food Safety Modernization ACT (FSMA). (1) Rapid detection of L. monocytogenes from contaminated RTE imported foods is critical in preventing the distribution of RTE food/food products contaminated with L. monocytogenes that continues to continuous to proliferate/multi[ply while in storage.