Yang Xiao, Dai Juan, Yang Li, Ma Ming, Zhao Su-Juan, Chen Xiang-Gui, Xiao Hang
School of Food and Bioengineering, Xihua University, Chengdu, PR China.
School of Laboratory Medicine, Chengdu Medical College, Chengdu, PR China.
J Sci Food Agric. 2018 May;98(7):2624-2631. doi: 10.1002/jsfa.8755. Epub 2017 Dec 11.
Enzyme inhibition-based detection is the most widely used method for rapid detection of organophosphorus pesticides (OPs) in food and agricultural products. However, the accuracy of the method is negatively affected by low inhibitory activities of OPs with PS moiety on acetylcholinesterase.
We demonstrated that oxidation pretreatments with bromine, hydrogen peroxide, or calcium hypochlorite significantly enhanced the enzyme inhibitory activities of these OPs. Especially, calcium hypochlorite (0.05%) pretreatment converted the PS moiety in OPs to PO and produced the most potent and steady inhibitory effect on the enzyme. This, in turn, resulted in a dramatic increase in the sensitivity of enzyme inhibition-based detection of these OPs by as much as 2 to 7 orders of magnitude. Importantly, this enhanced detection of OPs was validated in various vegetable samples.
Our findings provide a solid basis to use calcium hypochlorite pretreatment for the improved detection of OPs by the enzyme inhibition-based method. © 2017 Society of Chemical Industry.
基于酶抑制的检测方法是食品和农产品中有机磷农药（OPs）快速检测中应用最广泛的方法。然而，含PS基团的OPs对乙酰胆碱酯酶的抑制活性较低，会对该方法的准确性产生负面影响。
我们证明，用溴、过氧化氢或次氯酸钙进行氧化预处理可显著增强这些OPs的酶抑制活性。特别是，0.05%的次氯酸钙预处理可将OPs中的PS基团转化为PO，并对酶产生最强且最稳定的抑制作用。这进而使基于酶抑制的这些OPs检测灵敏度大幅提高，高达2至7个数量级。重要的是，这种增强的OPs检测方法在各种蔬菜样品中得到了验证。
我们的研究结果为使用次氯酸钙预处理通过基于酶抑制的方法改进OPs检测提供了坚实的基础。© 2017化学工业协会。
