矢车菊素-3-O-葡萄糖苷对水中丙溴磷的光降解抑制效应

Cyanidin-3-O-glucoside mediated photodegradation of profenofos in water

为明确丙溴磷在水中的光降解行为和黄酮类化合物矢车菊素-3-O-葡萄糖苷对丙溴磷光降解作用效应和机制,研究了高压汞灯光照下矢车菊素-3-O-葡萄糖苷对不同初始浓度丙溴磷光降解的影响,分别通过PNDA捕获羟基自由基和离子色谱法研究了丙溴磷光降解过程中羟基自由基和溴离子含量变化情况,并利用LC-MS-MS确定了丙溴磷光降解的初级产物。结果表明:高压汞灯光照下,3种浓度丙溴磷(5、25和50μmol·L^(-1))的光降解半衰期分别为8.97、12.36和13.15 min;加入摩尔浓度比1∶5的矢车菊素-3-O-葡萄糖苷后,丙溴磷的光降解半衰期分别延长了1.65倍、3.93倍和5.71倍。丙溴磷光降解过程中产生了羟基自由基,加入矢车菊素-3-O-葡萄糖苷后羟基自由基含量骤减;丙溴磷光降解反应体系中丙溴磷的降解摩尔量与溴离子产生摩尔量呈1∶1关系,而加入矢车菊素-3-O-葡萄糖苷后,溴离子产生摩尔量显著减少。丙溴磷初级光降解产物是O-(2-氯苯基)-O-乙基-S-丙基-硫代磷酸酯,添加矢车菊素-3-O-葡萄糖苷后不改变丙溴磷的光降解路径。研究结果将有助于明确丙溴磷在环境中的行为,尤其是环境中的黄酮类化合物对于丙溴磷光降解的影响效应,从而为评估丙溴磷使用后的潜在环境安全风险提供依据。

In order to investigate the photodegradation behavior of profenofos in water,and the effect of cyanidin-3-O-glucoside(C3G) on photodegradation of profenofos,in this paper,the effect of C3G on the photodegradation of profenofos at different initial concentrations under high pressure mercury lamp(HPML) was studied.The mechanism of profenofos photolysis was investigated by PNDA capture of hydroxyl and ion chromatography,respectively.The changes of hydroxyl radical and bromide ion content were determined,and the primary products of profenofos degradation were determined by LC-MS-MS.The results showed that the photodegradation half-lives of profenofos(5,25 and 50 μmol·L^(-1)) under HPML were 8.97,12.36 and 13.15 min,respectively.The photodegradation half-lives of profenofos were decreased by 1.65,3.93 and 5.71 times,respectively after treatment with 5 equivalent C3G.Under HPML irradiation,hydroxyl radical was generated hydroxyl radical was generated during profenofos photolysis,while hydroxyl radical concentration was decreased after addition of C3G.The mole of degrated profenofos was the same of generated bromide ions,and the amount of bromine ion decreased significantly in the presence of C3G.The primary photodegradation product of profenofos is O-(2-chlorophenyl)-O-ethylS-propyl-thiophosphate.The photodegradation pathway of profenofos does not change in the presence of C3G.These findings can improve the understanding of the photolytic effect of flavonoids on profenofos and are of significance for predicting the degradation kinetics of profenofos and accurately assessing its potential biological impacts.