title: Stereoselectivity in bioaccumulation and excretion of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae.
abstract: Stereoselectivity in bioaccumulation and excretion of stereoisomers of epoxiconazole by mealworm beetle (Tenebrio molitor) larvae through dietary exposure was investigated. Liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method that use a ChiralcelOD-3R[cellulosetris-Tris-(3, 5-dichlorophenyl-carbamate)] chromatography column was applied to carry out chiral separation of the stereoisomers. Wheat bran was spiked with racemic epoxiconazole at two dose levels of 20mg/kg and 2mg/kg (dry weight) to feed T. molitor larvae. The results showed that both the doses of epoxiconazole were taken up by Tenebrio molitor larvae rapidly at the initial stages. There was a significant trend of stereoselective bioaccumulation in the larvae with a preferential accumulation of (-)-epoxiconazole in the 20mg/kg dose. The stereoselectivity in bioaccumulation in the 2mg/kg dosage was not obvious compared to the 20mg/kg group. Results of excretion indicated an active excretion is an important pathway for the larvae to eliminate epoxiconazole which was a passive transport process with non stereoselectivity. The faster elimination might be the reason for the low accumulation of epoxiconazole, as measured by bioaccumulation factor (BAF).
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Xiaotian
authors.initials: X
authors.lastname: Lv
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Liu
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Yaobin
authors.initials: Y
authors.lastname: Li
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Yongxin
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Huili
authors.initials: H
authors.lastname: Wang
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Li
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China. Electronic address: guoby@rcees.ac.cn.
authors.forename: Baoyuan
authors.initials: B
authors.lastname: Guo
mesh_terms: D000818:Animals; D001835:Body Weight; D004032:Diet; D004852:Epoxy Compounds / Q000032:analysis / Q000378:metabolism*; D005659:Fungicides, Industrial / Q000032:analysis / Q000378:metabolism*; D007814:Larva / Q000378:metabolism; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry; D013712:Tenebrio / Q000378:metabolism*; D014230:Triazoles / Q000032:analysis / Q000378:metabolism*
chemical_list: D004852:Epoxy Compounds; D005659:Fungicides, Industrial; D014230:Triazoles; C109476:epoxiconazole
keywords: Bioaccumulation; Epoxiconazole; Excretion; Stereoselectivity; Tenebrio molitor larvae