title: Stereoselective degradation of benalaxyl in tomato, tobacco, sugar beet, capsicum, and soil.
abstract: The stereoselective degradation of the racemic benalaxyl in vegetables such as tomato, tobacco, sugar beet, capsicum, and the soil has been investigated. The two enantiomers of benalaxyl in the matrix were extracted by organic solvent and determined by validated chiral high-performance liquid chromatography with a cellulose-tris-(3, 5-dimethylphenylcarbamate)-based chiral column. Rac-benalaxyl was fortified into the soil and foliar applied to vegetables. The assay method was linear over a range of concentrations (0.5-50 microg ml(-1)) and the mean recoveries in all the samples were more than 70% for the two enantiomers. The limit of detection for both enantiomers was 0.05 microg g(-1). The results in soil showed that R-(-)-enantiomer dissipated faster than S-(+)-enantiomer and the stereoselectivity might be caused by microorganisms. In tomato, tobacco, sugar, beet, and capsicum plants, there was significantly stereoselective metabolism. The preferential absorption and degradation of S-(+)-enantiomer resulted an enrichment of the R-(-)-enantiomer residue in all the vegetables.
authors: Department of Applied Chemistry, China Agricultural University, Beijing, China.
authors: Xu
authors: X
authors: Gu
authors: Peng
authors: P
authors: Wang
authors: Donghui
authors: D
authors: Liu
authors: Chunguang
authors: C
authors: Lv
authors: Yuele
authors: Y
authors: Lu
authors: Zhiqiang
authors: Z
authors: Zhou
mesh_terms: D000042:Absorption; D000409:Alanine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D001711:Biotransformation; D002138:Calibration; D002212:Capsicum / Q000378:metabolism*; D019663:Chenopodiaceae / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D007700:Kinetics; D018551:Solanum lycopersicum / Q000378:metabolism*; D015203:Reproducibility of Results; D012987:Soil / Q000032:analysis*; D013237:Stereoisomerism
chemical_list: D012987:Soil; C052866:benalaxyl; D000409:Alanine