Abstract：
Guvermectin is a biopesticide isolated from the secondary metabolites of Streptomyces sp. NEAU6, an endogenous actinomyces of a Chinese medicine named Paris polyphylla. However, the environmental degradation behavior and biotoxicity of guvermectin are still unclear, which may affect its rational application. Therefore, the degradation of guvermectin in water at different pH values (pH 4, pH 6, pH 7, and pH 9) and with or without light was investigated in the laboratory. The results showed that guvermectin could be degraded in pH 4 solution, and the presence of light irradiation enhanced the degradation process with a DT50 of 2.95 and 12 days for photolysis and hydrolysis, respectively. However, guvermectin was fairly stable in other conditions. Three products transformed from guvermectin degradation were identified by UPLC-QTOF/MS. Biotoxicity assessment was performed on Danio rerio and Daphnia magna Straus by ECOSAR prediction and in vivo biological tests. The test data showed that guvermectin and its transformation products exhibited low toxicities to D. rerio and D. magna Straus (LC50/EC50 > 100 mg a.i./L), and the transformation products had lower toxicity than their parent substance. The results provided a reference for elucidating the potential risk of guvermectin to nontarget organisms and promoting its rational use.
摘要：
古维菌素是从链霉菌属的次生代谢产物中分离出的生物农药。NEAU6，一种名为巴黎多叶的中药的内源性放线菌。然而,古维菌素的环境降解行为和生物毒性尚不清楚，这可能会影响其合理应用。因此,在实验室中研究了在不同pH值（pH4，pH6，pH7和pH9）以及在有或没有光照的情况下，格维菌素在水中的降解。结果表明,在pH为4的溶液中,光辐射的存在增强了降解过程，光解和水解的DT50为2.95和12天，分别。然而,古维菌素在其他条件下相当稳定。通过UPLC-QTOF/MS鉴定了三种从古维菌素降解转化的产物。通过ECOSAR预测和体内生物学测试对Daniorerio和DaphniamagnaStraus进行了生物毒性评估。试验数据表明，格维菌素及其转化产物对雷里欧和麦格纳斯特劳斯具有低毒性(LC50/EC50>100mga.i./L)，转化产物的毒性低于其母体物质。研究结果可为阐明格维菌素对非靶标生物的潜在风险和促进其合理使用提供参考。
