去氢孕酮在水中的光化学转化过程及降解产物鉴定  

Phototransformation and photoproduct identification of dydrogesterone in water

作　　者：何智俐 高爽 李文彦[1] 李永涛[1] 杨行健 孙岩 HE Zhili;GAO Shuang;LI Wenyan;LI Yongtao;YANG Xingjian;SUN Yan(College of Natural Resources and Environment,South China Agricultural University,Guangzhou 510642,China;Agricultural Environment and Cultivated Land Quality Protection Center of Guangdong Province/Guangdong Agricultural and Rural Investment Project Center,Guangzhou 510640,China)

机构地区：[1]华南农业大学资源环境学院,广东广州510642 [2]广东省农业环境与耕地质量保护中心/广东省农业农村投资项目中心,广东广州510640

出　　处：《华南农业大学学报》2023年第4期495-503,共9页Journal of South China Agricultural University

基　　金：国家自然科学基金(42177367);广州市基础与应用基础研究(2023A04J1990)。

摘　　要：【目的】探究典型合成孕激素去氢孕酮(Dydrogesterone,DYD)在模拟太阳光下的光化学转化过程及转化路径。【方法】利用光化学反应器,测试模拟太阳光下DYD的光解动力学过程,探究不同pH(5、7和9)、温度(15、25和35℃)和天然有机质(Natural organic matter,NOM)质量浓度(0、5和20 mg·L^(-1))对DYD光解速率的影响,利用超高效液相色谱–飞行时间质谱(UHPLC-QTOF-MS)鉴定DYD光解后产生的潜在产物,并推测潜在的反应路径。【结果】光照条件下DYD浓度逐渐降低,说明DYD发生了光降解过程。DYD的光解速率受溶液初始pH影响不明显,一阶光解动力学速率常数(k)为0.015~0.019 h^(-1);DYD的光解速率在高温和低浓度NOM条件下有所提升(k从0.019 h^(-1)分别升至0.027和0.028 h^(-1)),但在高浓度NOM条件下被抑制。UHPLC-QTOF-MS分析表明,DYD在光解过程中共生成19种产物,主要为羟基化、加氢、缩聚、光异构化以及开环后的反应产物。【结论】DYD在地表水中会发生光降解作用,温度和NOM是影响其光解的重要因素;光解后形成的19种产物仍保留了DYD的分子骨架,因此可能仍具有潜在的内分泌干扰效应。【Objective】To explore the phototransformation of a synthetic progestin,dydrogesterone(DYD),under simulated sunlight,and identify its potential transformation pathways.【Method】Photoreactor was used to test the phototransformation process of DYD under simulated sunlight.Experiments were also conducted to explore different pH(5,7,and 9),temperature(15,25,and 35℃),and natural organic matter(NOM)concentration(0,5,and 20 mg·L^(−1))on DYD phototransformation rate.Ultra-high performance liquid chromatography-time of flight mass spectrometer(UHPLC-QTOF-MS)was used to identify the potential photoproducts of DYD,and the potential transformation pathways were speculated.【Result】The concentration of DYD decreased over time under simulated sunlight,indicating that phototransformation occurred in the system.DYD transformation rate was not obviously affected by the initial solution pH,and the first-order phototransformation kinetic rate constant(k)was 0.015−0.019 h^(−1).DYD transformation rate was facilitated by high temperature and low concentration of NOM(k increased from 0.019 h^(−1) to 0.027 and 0.028 h^(−1),respectively),but was inhibited by high concentration of NOM.UHPLC-QTOF-MS analysis showed that 19 photoproducts were generated during transformation,via hydroxylation,hydrogenation,polycondensation,and photoisomerization with subsequent ring-opening reactions.【Conclusion】Phototransformation will occur for DYD in surface water,and temperature and NOM play important roles in DYD phototransformation.A total of 19 photoproducts detected in this study remain the basic molecular skeleton of DYD,indicating that these products would exhibit potential endocrine disruption to aquatic systems.

关 键 词：合成孕激素 去氢孕酮 光降解 光解产物 内分泌干扰 

分 类 号：S19[农业科学—农业基础科学] X592[环境科学与工程—环境工程]