Enantioselective degradation of metalaxyl in cucumber, cabbage, spinach and pakchoi

• Published in: Chemosphere (Oxford) 2014, Vol.95, p.241-246
• Main Authors: Wang, Meiyun, Zhang, Qing, Cong, Lujing, Yin, Wei, Wang, Minghua
• Format: Article
• Language: English
• Subjects: Agrochemicals products; Alanine - analogs & derivatives; Alanine - metabolism; Biological and medical sciences; Brassica - metabolism; Brassica rapa subsp. chinensis; cabbage; cellulose; cucumbers; Cucumis sativus - metabolism; enantiomers; Food industries; food safety; formic acid; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; Fungicides, Industrial - metabolism; greenhouses; metalaxyl; Other agrochemicals used in plant protection (herbicides, fungicides, etc.); Phytopathology. Animal pests. Plant and forest protection; Pollution effects and side effects of agrochemicals on crop plants and forest trees. Other anthropogenic factors; Pollution effects. Side effects of agrochemicals; reversed-phase high performance liquid chromatography; risk; Soil Pollutants - metabolism; spinach; Spinacia oleracea - metabolism; stereochemistry; Stereoisomerism
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2013.08.084

The enantioselective degradation behaviors of the acylamino acid fungicide metalaxyl in vegetables (cucumber, cabbage, spinach and pakchoi) under field and greenhouse conditions were elucidated by reversed-phase high-performance liquid chromatography (HPLC). A cellulose tris (3-chloro-4-methyl phenyl carbamate) chiral column (Lux Cellulose-2) was used for the chiral separation of the enantiomers using acetonitrile-0.1% formic acid solution (40:60, v/v) as mobile phase at a flow rate of 1.0 mL min(-1). The two enantiomers could be completely separated with a resolution (Rs) of 5.2. The linearity range, matrix effect, precision and recovery were evaluated. The method was successfully applied for the enantioselective analysis of metalaxyl in cucumber, cabbage, spinach and pakchoi under different conditions. The results showed that R-enantiomer dissipated faster than S-enantiomer in cucumber of greenhouse. Inversely, a preferential degradation of S-form was found in spinach and pakchoi under field and greenhouse conditions. No stereoselective degradation in cabbage was observed. These results can be applied for evaluating the environmental risk and food safety.