The Kinetics and Mechanisms for Photodegradation of Nitrated Polycyclic Aromatic Hydrocarbons on Lettuce Leaf Surfaces: An In Vivo Study
The Kinetics and Mechanisms for Photodegradation of Nitrated Polycyclic Aromatic Hydrocarbons on Lettuce Leaf Surfaces: An In Vivo Study
复制标题
生菜叶表面硝化多环芳烃光降解动力学和机理：体内研究
DOI：
10.1021/acs.jafc.9b02326
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发表时间：
2019
影响因子：
6.1
通讯作者：
Lu Haoliang
中科院分区：
文献类型：
--
作者：
Sun Haifeng;Wang Meng;Nan Yanli;Han Ming;Lu Haoliang
了解食用蔬菜中硝化多环芳烃（NPAHs）的环境归宿，对于更好地评估NPAHs通过膳食途径暴露于人体具有重要意义。本文首次将石墨烯量子点作为荧光探针，应用荧光猝灭法对生菜叶片表面吸附的9-硝基蒽（9-NAnt）和1-硝基芘（1-NPyr）进行了活体检测。幼苗此外，还对两种吸附态NPAHs的光解动力学和机理进行了探讨。光降解动力学符合准一级动力学方程，1-NPyr的光降解半衰期（7.4 ± 0.2 h）大于9-NAnt的光降解半衰期（2.3 ± 0.1 h）。蒽醌和芘二酮分别是9-NAnt和1-NPyr的主要光解产物。分子内重排是NPAH光解的最合理的机理。光解驱动的降解表现出关键的作用，清除NPAH的蔬菜叶，表明减少NPAH在食物链中的运输。
Insights into the environmental fates of nitrated polycyclic aromatic hydrocarbons (NPAHs) in edible vegetables are of great significance for better evaluating human exposure to NPAHs through the dietary pathway. In this work, a fluorescence quenching method using graphene quantum dots as a fluorescent probe was first applied for the in vivo determination of 9-nitroanthracene (9-NAnt) and 1-nitropyrene (1-NPyr) adsorbed on the leaf surfaces of living lettuce (Lactuca sativaL.) seedlings. Moreover, the photolysis kinetics and mechanisms of the two adsorbed NPAHs were discussed. The photodegradation kinetics followed the pseudo-first-order equation, and the photodegradation half-life of 1-NPyr (7.4 ± 0.2 h) was greater than that of 9-NAnt (2.3 ± 0.1 h). Anthraquinone and pyrenediones were identified to be the main photolytic products of 9-NAnt and 1-NPyr, respectively. Intramolecular rearrangement was the most reasonable mechanism for the NPAH photolysis. The photolysis-driven degradation exhibited a key role in scavenging NPAHs from the vegetable leaf, indicating the reduction of NPAH transportation in the food chain.