title: Determination of fungicides in white grape bagasse by pressurized liquid extraction and gas chromatography tandem mass spectrometry.
abstract: Ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) followed by gas chromatography-triple quadrupole-mass spectrometry (GC TQ-MS) were used for the rapid determination of 11 fungicides (metalaxyl, cyprodinil, procymidone, iprovalicarb, myclobutanyl, kresoxim-methyl, benalaxyl, fenhexamide, tebuconazole, iprodione and dimethomorph) in white grape bagasse. The extractions were optimized on real non-spiked samples by means of experimental design and the optimal conditions were selected to achieve the method validation. The PLE procedure showed much higher efficiency than UAE for the target fungicides. Under the selected extraction conditions, PLE showed satisfactory linearity, repeatability and reproducibility. Recoveries for the majority of studied fungicides were higher than 80% with relative standard deviations (RSD) lower than 12%. Limits of detection (LODs) for GC TQ-MS were very low, at the sub ngg(-1) for the majority of the target fungicides, well below the European maximum residue limits (MRLs) for wine and table grapes, and vine leaves. Eighteen white grape bagasse samples were analyzed and nine out of eleven targets were detected in the samples. Seven of them were detected in more than 50% of the samples and most samples contained at least four of the target analytes. The most frequently found compounds were tebuconazole and dimethomorph with concentrations between 1.6-130 and 2.0-1788ngg(-1), respectively. Some samples showed high levels of many of the studied fungicides (high ngg(-1), even μgg(-1) for cyprodinil, fenhexamide, iprodione and dimethomorph), but all of them below the European maximum residue limits (MRLs) for wine grapes.
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
authors.forename: Maria
authors.initials: M
authors.lastname: Celeiro
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain. Electronic address: maria.llompart@usc.es.
authors.forename: Maria
authors.initials: M
authors.lastname: Llompart
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
authors.forename: J Pablo
authors.initials: JP
authors.lastname: Lamas
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Lores
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, Faculty of Chemistry, Campus Vida, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Garcia-Jares
authors.affiliation: Galician Institute for Food Quality (INGACAL), Agronomic and Agrarian Research Centre (CIAM), E-15080 A Coruña, Spain.
authors.forename: Thierry
authors.initials: T
authors.lastname: Dagnac
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D005659:Fungicides, Industrial / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D057230:Limit of Detection; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*; D027843:Vitis / Q000737:chemistry*; D014920:Wine / Q000032:analysis*
chemical_list: D005659:Fungicides, Industrial; D002482:Cellulose; C027433:bagasse
keywords: Bagasse; Fungicides; GC–MS; GC–TQ-MS; Pressurized liquid extraction; Ultrasound-assisted extraction