Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China.
Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, PR China.
Sci Total Environ. 2018 Sep 1;634:875-883. doi: 10.1016/j.scitotenv.2018.03.375. Epub 2018 Apr 11.
Prothioconazole is a widely used chiral triazole fungicide. In this work, the enantioselective degradation and transformation of prothioconazole and its chiral metabolite prothioconazole-desthio in five kinds of soils were investigated under native and sterile conditions using reversed phase liquid chromatography tandem mass spectrometry with a Lux-cellulose-1 column. The results showed that an enantioselective degradation was observed with R-prothioconazole preferentially degraded in the five soils and enantiomeric fraction values that ranged from 0.32 to 0.41 under native conditions. Furthermore, the major metabolite prothioconazole-desthio was formed rapidly during prothioconazole dissipation. The prothioconazole-desthio enantiomers were degraded slowly, and there was a slight enantioselectivity with enantiomeric fraction values that ranged from 0.45 to 0.51 in the Nanjing and Jilin soils. Under sterile conditions, prothioconazole and its metabolite enantiomers were more slowly degraded with no enantioselectivity. The result of the incubation experiment with single enantiomers verified that R- and S-prothioconazole were transformed to R- and S-prothioconazole-desthio, respectively. No enantiomerization for prothioconazole and its chiral metabolite was observed. In addition, the excellent correlation between organic matter content and degradation rate indicated that organic matter could promote the degradation of prothioconazole and its metabolite enantiomers. The data in this study provide the experimental evidence of the stereoselective degradation and metabolism of both prothioconazole and its chiral metabolite in the environment.
丙硫菌唑是一种广泛使用的手性三唑类杀菌剂。在这项工作中，采用反相液相色谱串联质谱法，在天然和无菌条件下，使用 Lux-cellulose-1 柱，研究了丙硫菌唑及其手性代谢物丙硫菌唑-脱巯基在五种土壤中的对映选择性降解和转化。结果表明，在五种土壤中，R-丙硫菌唑优先降解，表现出对映选择性降解，在天然条件下，对映体分数值范围为 0.32 至 0.41。此外，在丙硫菌唑降解过程中，主要代谢物丙硫菌唑-脱巯基迅速形成。丙硫菌唑-脱巯基对映异构体降解缓慢，在南京和吉林土壤中，对映体分数值范围为 0.45 至 0.51，表现出轻微的对映选择性。在无菌条件下，丙硫菌唑及其代谢物对映异构体的降解速度更慢，没有对映选择性。单一对映体的孵育实验结果表明，R-和 S-丙硫菌唑分别转化为 R-和 S-丙硫菌唑-脱巯基。未观察到丙硫菌唑及其手性代谢物的对映体转化。此外，有机物质含量与降解速率之间的良好相关性表明，有机物质可以促进丙硫菌唑及其代谢物对映异构体的降解。本研究的数据为丙硫菌唑及其手性代谢物在环境中的立体选择性降解和代谢提供了实验证据。
