These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Stereoselective dissipation of epoxiconazole in grape (Vitis vinifera cv. Kyoho) and soil under field conditions.
    Author: Liang H, Qiu J, Li L, Li W, Zhou Z, Liu F, Qiu L.
    Journal: Chemosphere; 2012 May; 87(8):982-7. PubMed ID: 22414382.
    Abstract:
    Stereoselective dissipation of epoxiconazole had been studied in grape and soil during plant growing under field conditions in this paper. A sensitive and rapid chiral method was developed and validated for the determination of epoxiconazole stereoisomers in grape and soil based on liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS). Phenomenex Lux Cellulose-1 column was used for enantioseparation with a mixture of acetonitrile/water (90/10, v/v) as mobile phase at flow rate of 0.3 mL min(-1). Fortified recoveries in grape and soil samples ranged from 76.0% to 91.9% and relative standard deviations were less than 11.4% with fortified levels of 0.025-1.0 mg kg(-1). The limits of detection and quantification were 0.005 mg kg(-1) and 0.025 mg kg(-1), respectively, with linear calibration curves extending up to 5.0 mg kg(-1). The field experimental results showed that dissipations of epoxiconazole stereoisomers in grape followed first-order kinetics (R(2)>0.92) and stereoselectivity occurred in 2 h after spraying. The (-)-stereoisomer with half-life of 9.3 d degraded faster than (+)-stereoisomer with that of 13.2 d, and resulted in relative enrichment of (+)-stereoisomer. However, the stereoisomeric dissipations in soil were triphasic ("increase-decrease-steady") with lower dissipation rates, and also occurred with preferential degradation of (-)-stereoisomer under field condition. The results for stereoselective dissipations can be applied for food and environmental assessments of chiral pesticides.
    [Abstract] [Full Text] [Related] [New Search]