Abstract：
The chiral pesticide famoxadone is mainly applied to control fungal diseases on fruiting vegetables. The fungicidal activity, ecotoxicological effects, and degradation behavior of famoxadone enantiomers are less well known. In this study, a systemic assessment of the stereoselectivity of famoxadone was performed in cucurbits and soil. Famoxadone enantiomers presented distinct inhibitory activities among different fungal species. The bioactivities of R-(-)-famoxadone were 2.7-178 times higher than S-(+)-famoxadone toward five phytopathogens. Based on the obtained LC50 values, famoxadone was super toxic to Eisenia foetida (E. foetida). Moreover, the acute toxicity of R-(-)-famoxadone presented 167 times greater to E. foetida than that of S-(+)-famoxadone, indicating that R-(-)-famoxadone showed higher bioactivity toward target organisms and non-target organisms than S-(+)-famoxadone. In addition, a simple high-performance liquid chromatography (HPLC) method was established to determine the stereoselective degradation of famoxadone in two species of cucurbits (cucumber and chieh-qua) and in field soil. The half-life values of famoxadone degradation were from 5.4 to 14.1 days, indicating that famoxadone was easily degraded. Additionally, no stereoselective degradation was found in cucurbits and soil. The results may provide promising implications for comprehensive environmental and ecological risk assessments of famoxadone.
摘要：
手性农药法莫沙酮主要用于控制水果蔬菜的真菌疾病。杀真菌活性，生态毒理学影响，和法莫沙酮对映体的降解行为不太为人所知。在这项研究中,在瓜类和土壤中对法莫沙酮的立体选择性进行了系统评估。法莫沙酮对映体在不同真菌物种中表现出不同的抑制活性。R-（-）-法莫沙酮对五种植物病原体的生物活性比S-（）-法莫沙酮高2.7-178倍。根据获得的LC50值，法莫沙酮对foetida爱胜英具有超毒性(E.foetida）。此外，R-（-）-法莫沙酮对E.foetida的急性毒性比S-（）-法莫沙酮高167倍，表明R-（-）-法莫沙酮对靶生物和非靶生物显示出比S-（）-法莫沙酮更高的生物活性。此外,建立了一种简单的高效液相色谱（HPLC）方法，以测定法莫沙酮在两种瓜类（黄瓜和chieh-qua）和田间土壤中的立体选择性降解。法莫沙酮降解的半衰期值为5.4至14.1天，表明法莫沙酮容易降解。此外,在瓜类和土壤中未发现立体选择性降解。结果可能会为法莫沙酮的全面环境和生态风险评估提供有希望的意义。
