Food Science and Technology, Department of Food Science and Technology, Islamic Azad University, Science and Research Branch, Tehran, Iran.
Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Int J Biol Macromol. 2018 Feb;107(Pt B):1732-1737. doi: 10.1016/j.ijbiomac.2017.10.052. Epub 2017 Oct 10.
Under favorable growth conditions, Staphylococcus aureus infects and causes illnesses in humans and animals. Staphylococcal enterotoxins are considered the most important factor for food poisoning, with these toxins usually found in milk and its byproducts. This study investigated the presence of a classical enterotoxin of S. aureus (enterotoxin A) in raw cow milk samples obtained from Region 3 of Tehran. Sixty cow milk samples were collected from traditional dairy sales centers in the study site. Electrophoresis, high-performance liquid chromatography, sandwich ELISA, and direct ELISA were evaluated as methods for detecting toxins in the milk. A direct ELISA kit was designed, with the best factors, the most suitable densities, and the most optimal temperatures and temporal incubation conditions incorporated into the design. Among the evaluated methods, direct ELISA exhibited the highest accuracy in toxin detection. The designed kit achieved a correctness coefficient of 0.98 and detected enterotoxin A in 23% of the samples. It also exhibited a relative sensitivity and other features that are comparable to those of other bacterial detection techniques. Finally, the kit achieved good matching and repetition results, and no cross-reactions occurred between enterotoxins during the procedure.
在有利的生长条件下，金黄色葡萄球菌会感染人类和动物并导致疾病。葡萄球菌肠毒素被认为是食物中毒的最重要因素，这些毒素通常存在于牛奶及其副产品中。本研究调查了德黑兰第 3 区采集的生牛乳样本中是否存在金黄色葡萄球菌的一种经典肠毒素（肠毒素 A）。从研究地点的传统奶制品销售中心采集了 60 份牛乳样本。电泳、高效液相色谱、夹心 ELISA 和直接 ELISA 被评估为检测牛奶中毒素的方法。设计了一种直接 ELISA 试剂盒，其中纳入了最佳因素、最适合的密度以及最优化的温度和时间孵育条件。在所评估的方法中，直接 ELISA 在毒素检测方面表现出最高的准确性。设计的试剂盒的正确性系数为 0.98，检测出 23%的样本中存在肠毒素 A。它还表现出与其他细菌检测技术相当的相对灵敏度和其他特征。最后，试剂盒在匹配和重复方面取得了良好的结果，在检测过程中不会发生肠毒素之间的交叉反应。
