抑霉唑手性异构体及其代谢物在柑橘贮藏中的选择性行为  

Selective behavior of imazalil enantiomers and its metabolites in citrus storage

作　　者：姚周麟 章虎[2] 吴韶辉[2] 林媚[2] 王强[2] 李祖光[1] YAO Zhoulin;ZHANG Hu;WU Shaohui;LIN Mei;WANG Qiang;LI Zuguang(Zhejiang University of Technology,Hangzhou 310014,China;Zhejiang Academy of Agriculture Sciences,Hangzhou 310021,China)

机构地区：[1]浙江工业大学,杭州310014 [2]浙江省农业科学院,杭州310021

出　　处：《农药学学报》2022年第1期142-151,共10页Chinese Journal of Pesticide Science

基　　金：国家自然科学基金(31801642).

摘　　要：本研究确定了抑霉唑及其代谢产物咪唑乙醇的绝对构型,建立了一种基于超高效液相色谱-串联质谱检测柑橘不同部位抑霉唑和咪唑乙醇对映体的手性分析方法,并开展了柑橘贮藏过程中抑霉唑的选择性降解行为研究。柑橘(椪柑Citrus reticulata Blanco cv.Ponkan)果肉、全果和果皮样品通过乙腈(含体积分数1%的乙酸)提取,抑霉唑和咪唑乙醇分别采用Lux Cellulose-2和Chiralpak IG-3手性柱分离对映体。结果表明:抑霉唑和咪唑乙醇对映体在0.001~0.5 mg/L范围内线性关系良好(R^(2)>0.9915,>0.9991),方法定量限(LOQ)均为0.0005 mg/kg;4个添加水平(0.0005、0.05、0.125、0.25 mg/kg)在不同基质中的平均回收率分别为78%~101%和73%~105%,相对标准偏差(RSD)分别为0.4%~2.9%和0.4%~5.6%。抑霉唑在柑橘中的贮藏降解符合一级动力学方程,R-抑霉唑在全果和果皮中的半衰期分别为136 d和158 d,S-抑霉唑在全果和果皮中半衰期分别为77 d和82 d,即S-抑霉唑的降解速率明显快于R-抑霉唑;其代谢产物S-咪唑乙醇在柑橘果实各部位的积累速度均高于R-咪唑乙醇。The absolute configuration of imazalil and its metabolite imidazol ethanol was determined.A chiral analysis method based on high performance liquid chromatography-tandem mass spectrometry was established for the determination of imazalil and imidazol ethanol in different parts of citrus.The selective degradation behavior of imazalil during citrus storage was studied.Orange pulp,whole fruit and orange peel(Citrus reticulata Blanco cv.Ponkan)samples were extracted by acetonitrile(containing 1%acetic acid by volume).Enantiomers of imazalil and imidazol ethanol were separated by chiral column of Lux Cellulose-2 and Chiralpak IG-3,respectively.The linear range of imazalil and imidazol ethanol enantiomers was 0.001~0.5 mg/L(R^(2)>0.9915,>0.9991).The limit of quantification(LOQ)of the method was 0.0005 mg/kg.The average recoveries of the four supplemental levels(0.0005,0.05,0.125 and 0.25 mg/kg)in different substrates were 78%-101%and 73%-105%,with relative standard deviations(RSDs)of 0.4%-2.9%and 0.4%-5.6%,respectively.The storage and degradation of imazalil in orange conforms to the first-order kinetic equation.The half-lives of R-imazalil in whole orange and orange peel were 136 d and 158 d,respectively,while those of S-imazalil in whole orange and orange peel were 77 d and 82 d,respectively.The degradation rate of S-imazalil was significantly faster than that of R-imazalil.The accumulation velocity of S-imidazole ethanol was higher than that of Rimidazole ethanol in different parts of orange fruits.

关 键 词：抑霉唑 咪唑乙醇 手性拆分 代谢产物 柑橘贮藏 降解行为 超高效液相色谱-串联质谱 

分 类 号：O657.63[理学—分析化学] TQ450.26[理学—化学]