| Summary: | 碩士 === 國立臺灣大學 === 農業化學研究所 === 98 === Dicarboximide fungicide vinclozolin was found to have the anti-androgen effects, and its metabolites, M1 (2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3-butenoic acid) and M2 (3’,5’-dichloro-2-hydroxy-2-methylbut-3-enanilide), were found to have more affinity to androgen receptors than vinclozoline. In this study, the effect of vinclozolin metabolites in soil on its persistence and soil microbial populations diversity were investigated. The toxicity of vinclozolin on Daphnia pulex, were compared with 2 kinds of its metabolites. First, we extract vinclozolin from commmerical products and then perform chemical hydrolysis to collect the metabolites. The soil sample were collected from Taoyuan District Agricultural Research (Pu) and Extension Center and Hualien District Agricultural Research (Wl). The experimental concentration were 20.0 mg kg-1 for M1 and 5.0 mg kg-1 for M2. We used solvent phase extraction to extract residues from soil, and utilized HPLC-DAD to detect them. In sterilized soil, M1 and M2 have longer half-lives (10.9-126.6 and 87.1-296.5 day) than vinclozolin (8.7-35.0 day). The impact of vinclozolin metabolites on soil microbial community were analysed by PCR-DGGE. In the DGGE patterns, we could discover some original superior populations with the resisence to toxicity of metabolites, such as Acidobacterium sp. and Pseudomonas sp. in Pu soil, and Ammoniphilus oxalaticus in Wl soil had the resistence to M1 or M2. But some populations were disappeared or enlarged by metabolites treatment, such as Pseudomonas sp. and Bacillus sp. did enlarge their population in treated soil. We conducted 48 hr acute toxicity assay on daphnia. The result of toxicity are in the sequence of M2 >vinclozolin>M1. The metabolites from degradation of vinclozolin, still have the hazard on environment. Due to vinclozolin metabolites have characteristics of persistence and toxicity. When we assess the impact of vinclozolin on environment, the effect of metabolites should be taken into account.
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