Enantioselective Environmental Behavior of the Chiral Herbicide Fenoxaprop-ethyl and Its Chiral Metabolite Fenoxaprop in Soil
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- 作者：Yanfeng Zhang ; Donghui Liu ; Jinling Diao ; Zeying He ; Zhiqiang Zhou ; Peng Wang ; Xuefeng Li
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2010
- 出版时间：December 22, 2010
- 年：2010
- 卷：58
- 期：24
- 页码：12878-12884
- 全文大小：810K
- 年卷期：v.58,no.24(December 22, 2010)
- ISSN：1520-5118
文摘
The enantioselective degradation behavior of fenoxaprop-ethyl (FE) and its chiral metabolite fenoxaprop (FA) in three soils under native conditions was investigated. Two pairs of enantiomers were analyzed by high-performance liquid chromatography (HPLC) with an amylose tri-(3,5-dimethylphenylcarbamate) (ADMPC) chiral column. The degradation of racemic FE in three soils showed the herbicidally inactive S-(−)-enantiomer degraded faster than the active R-(+)-enantiomer. FE was configurationally stable in soils because no interconversion to the respective antipodes was observed during incubation of the enantiopure S-(−)- or R-(+)-FE. The main metabolites of FE were confirmed as FA and 6-chloro-2,3-dihydrobenzoxazol-2-one (CDHB), and the formation of the chiral metabolite FA showed enantioselectivity in soils. The degradation of rac-FA was also enantioselective with the S-(−)-FA preferentially degraded: the half-life (t1/2) of the S-form in the three soils ranged from 2.03 to 5.17 days, and that of R-form ranged from 2.42 to 20.39 days. The inversion of the S-(−)-enantiomer into the R-(+)-enantiomer occurred in two of the three soils when the enantiopure S-(−)- and R-(+)-FA were incubated. The data from sterilized control experiments indicated that the enantioselectivity of FE and FA was attributed to microbially mediated processes.