Hu Jin, Liu Yingjie, Zhao Ying, Gan Yantai, Hill Robert Lee, Zhang Hongyuan
Ludong University, Yantai, 264025, China.
Staff Development Institute of China National Tobacco Corporation, Zhengzhou, 450007, China.
Environ Res. 2025 Aug 1;278:121682. doi: 10.1016/j.envres.2025.121682. Epub 2025 Apr 23.
Triazole fungicides occupy a significant position in the global fungicidal market. Mefentrifluconazole (MFZ) is a new-generation chiral triazole fungicide with broad applications. It can effectively control several rice fungal diseases; thus, its wide application increases its risk of entering the water and sediment in ecosystems. In this study, the stereoselective fate and risk of MFZ in the water-sediment system were investigated. The results showed stereoselective differences in the acute toxicity and fate of MFZ enantiomers (S-MFZ and R-MFZ) in the water-sediment system, with S-MFZ being more toxic and persistent. Both R-MFZ and S-MFZ induced significant decreases in the oxidation-reduction potential (ORP) value and organic matter (OM) content of the sediment. Additionally, soil enzyme activity in the sediments changed in varying degrees during exposure. Further microbiome sequencing results showed that both R-MFZ and S-MFZ induced changes in the composition of sediment microbial communities and decreased species diversity, which, in turn, affected the metabolic processes of microorganisms and the function of glycosyltransferase (GT) enzymes, especially S-MFZ. Correlation analysis showed that stereoselectivity in the interaction between the MFZ enantiomers and GT enzymes induced a difference in the synthesis of lipopolysaccharides; thus, affecting the abundances of the relevant bacterial genera and carbohydrate metabolic pathways. Exposure to MFZ enantiomers induced an increase in the abundance of anaerobic bacteria, such as Methylophilus and Rhodoferax, which exacerbated the anaerobic environment of the sediment system, leading to acidification and accelerated nutrient decomposition.
三唑类杀菌剂在全球杀菌剂市场中占据重要地位。甲氟康唑（MFZ）是一种具有广泛应用的新一代手性三唑类杀菌剂。它能有效防治多种水稻真菌病害；因此，其广泛应用增加了它进入生态系统水体和沉积物的风险。在本研究中，调查了MFZ在水-沉积物系统中的立体选择性归趋和风险。结果表明，MFZ对映体（S-MFZ和R-MFZ）在水-沉积物系统中的急性毒性和归趋存在立体选择性差异，S-MFZ毒性更强且更持久。R-MFZ和S-MFZ均导致沉积物的氧化还原电位（ORP）值和有机质（OM）含量显著降低。此外，暴露期间沉积物中的土壤酶活性有不同程度的变化。进一步的微生物组测序结果表明，R-MFZ和S-MFZ均导致沉积物微生物群落组成发生变化并降低了物种多样性，进而影响微生物的代谢过程和糖基转移酶（GT）的功能，尤其是S-MFZ。相关性分析表明，MFZ对映体与GT酶相互作用中的立体选择性导致脂多糖合成存在差异；因此，影响了相关细菌属的丰度和碳水化合物代谢途径。暴露于MFZ对映体导致嗜甲基菌属和红环菌属等厌氧菌丰度增加，这加剧了沉积物系统中的厌氧环境，导致酸化并加速养分分解。
