Isaac Ann Mary, Kolla Harish Babu, Pallavi K P, Bandyadka Sharat, Mhatre Chinmayi Nandkishor, Urs Radhika Madan, Kingston J Joseph
Defence Institute of Biodefence Technologies (DIBT-DRDO), Mysore, India.
Front Microbiol. 2025 Jul 16;16:1517680. doi: 10.3389/fmicb.2025.1517680. eCollection 2025.
, a well-known food-borne zoonotic pathogen, is the causative agent of Salmonellosis affecting public health in both developed and developing countries. Traditional detection methods are time-consuming, involving multiple steps like pre-enrichment, selective plating, and biochemical confirmation. In this study, a faster and sensitive TaqMan real-time PCR assay was developed with a 6 h enrichment paradigm for the direct detection of from food matrices using a novel target gene, , which is part of the Type 3 Secretion System (T3SS). The assay was found to be highly specific and had a limit of detection of 10 CFU/mL in pure culture. With a 6-h enrichment step, the assay was able to detect even low bacterial inoculum like 10 CFU/mL of Typhimurium in both artificially contaminated raw foods (raw egg and frozen chicken) and cooked Indian food matrices (ready-to-eat chicken biriyani and chicken pulao). The assay demonstrated 100% relative sensitivity, specificity, and accuracy across 52 natural (raw and processed) food samples. In summary, the real-time detection method developed is faster, specific, sensitive and a potential tool for regular monitoring in diverse food matrices within 8 h.
作为一种著名的食源性人畜共患病原体，是沙门氏菌病的病原体，在发达国家和发展中国家均影响公众健康。传统检测方法耗时较长，涉及预富集、选择性平板接种和生化确认等多个步骤。在本研究中，开发了一种更快且灵敏的TaqMan实时PCR检测方法，采用6小时富集模式，利用一种新型靶基因（作为3型分泌系统（T3SS）的一部分）直接从食品基质中检测。该检测方法具有高度特异性，在纯培养物中的检测限为10 CFU/mL。经过6小时的富集步骤，该检测方法能够在人工污染的生食（生鸡蛋和冷冻鸡肉）和熟制印度食品基质（即食鸡肉比尔亚尼和鸡肉抓饭）中检测到低至10 CFU/mL的鼠伤寒沙门氏菌等低细菌接种量。该检测方法在52份天然（生的和加工过的）食品样本中显示出100%的相对灵敏度、特异性和准确性。总之，所开发的实时检测方法更快、特异、灵敏，是在8小时内对多种食品基质进行常规监测的潜在工具。
