Key Laboratory of Environment Correlative Dietology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.
Jingzhou Institute for Food and Drug Control, Jingzhou 434000, Hubei, China.
Food Res Int. 2022 Jun;156:111279. doi: 10.1016/j.foodres.2022.111279. Epub 2022 May 3.
Salmonella, especially drug-resistant Salmonella poses a serious threat to food safety and human health. Herein, we proposed a rapid, accurate and sensitive phage amplification-based analysis (PAA) based on an isolated Salmonella phage T156 with broad host range and potent lysis ability for the quantification of viable Salmonella, as well as rapid antibiotic susceptibility testing. This assay has been successful applied to quantify viable Salmonella in food matrices such as milk and lettuce, with a detection limit of 1 colony forming units (CFU) /mL and high specificity for only detect live bacteria not dead bacteria. When combined with real-time PCR (qPCR), PAA-qPCR further reduced the detection time from 6.5 h to 3.5 h, with a detection limit of 10 CFU/mL and without complicate DNA extraction or purification process. Moreover, this assay could also specifically detect drug-resistant Salmonella, shortening the detection time from 24 h to 6.5 h. The results were consistent with that of the conventional paper disc diffusion method (DDM). These PAA methods were evaluated and applied for Salmonella quantification, as well as the detection of drug-resistant Salmonella, providing a promising platform to trace the foodborne pathogen in the complex food matrix, as well as the detection of drug-resistant Salmonella.
沙门氏菌，尤其是耐药性沙门氏菌，对食品安全和人类健康构成严重威胁。在此，我们提出了一种快速、准确和敏感的噬菌体扩增分析（PAA）方法，该方法基于一种具有广泛宿主范围和强大裂解能力的分离沙门氏菌噬菌体 T156，可用于定量活的沙门氏菌，以及快速抗生素敏感性测试。该方法已成功应用于定量牛奶和生菜等食品基质中的活沙门氏菌，检测限为 1 个菌落形成单位（CFU）/mL，特异性高，只能检测活细菌而不是死细菌。当与实时 PCR（qPCR）结合使用时，PAA-qPCR 进一步将检测时间从 6.5 小时缩短至 3.5 小时，检测限为 10 CFU/mL，且无需复杂的 DNA 提取或纯化过程。此外，该方法还可以特异性检测耐药性沙门氏菌，将检测时间从 24 小时缩短至 6.5 小时。结果与传统纸片扩散法（DDM）一致。这些 PAA 方法已被评估并应用于沙门氏菌定量以及耐药性沙门氏菌的检测，为在复杂的食品基质中追踪食源性病原体以及检测耐药性沙门氏菌提供了一个有前途的平台。
