In this study, the hydrolysis of diclofop-methyl (DM) in aqueous system and the bioaccumulation of its main metabolite, Diclofop (DA), in the tubifex worms were investigated using enantioselective high-performance liquid chromatography. With the addition of tubifex, rapid hydrolysis was observed for DM. It is revealed that the hydrolysis of DM in the water and the accumulation of DA in the worms were both enantioselective. Meanwhile, either the hydrolysis amount or the levels of enantioselectivity were influenced by the tubifex. After incubated for 24 h, about 94.6% of the DM was hydrolyzed and the enantiomer fraction of metabolite (DA) deviated from 0.5 with R-DA significantly higher than S-DA. The enantiopure S-DM and R-DM and S-DA and R-DA were incubated, and enantiomerizations were detected between the two DM enantiomers with S-form inversing into R-form and vice versa. It was found that the S-DM exhibited a higher tendency to invert than the R-DM.

中文翻译：

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甲基敌草灵对映体化和对映选择性生物累积

本研究采用对映选择性高效液相色谱法研究了甲基敌草灵 (DM) 在水系统中的水解及其主要代谢物敌草灵 (DA) 在线虫体内的生物累积情况。添加 Tubifex 后，观察到 DM 快速水解。结果表明，水中DM的水解和蠕虫体内DA的积累均具有对映选择性。同时，水解量或对映选择性水平受到tubifex的影响。孵育24小时后，约94.6%的DM被水解，代谢物（DA）的对映体分数偏离0.5，其中R -DA显着高于S -DA。将对映体纯的S -DM和R -DM以及S -DA和R -DA温育，并检测两种DM对映体之间的对映体化，其中S-形式反转为R-形式，反之亦然。发现S -DM表现出比R -DM更高的反转倾向。