title: Supercritical fluid extraction of resveratrol from grape skin of Vitis vinifera and determination by HPLC.
abstract: Supercritical fluid extraction of resveratrol from grape skin of Vitis vinifera was studied. Extraction variables such pressure, modifier concentration (ethanol), and extraction time were optimised. Final extraction conditions were: 40 degrees C, 150 bar, 7.5% ethanol and extraction time 15 min. Extraction recovery and precision (variation coefficient between 0.2 and 1.0%) were calculated. The resveratrol content in the ethanolic extract was determined by HPLC with UV detection at 306 nm. Acetic acid-methanol-water was used as the mobile phase, and C-18 and C-8 columns were tested, instrumental parameters were optimised, and analytical parameters were calculated (lineal interval 0-75 mg l(-1), detection limit 0.1 mg l(-1), sensitivity 125530 mg(-1) mg l(-1), coefficient variation 0.8-1.6%). Six different varieties of grape skin, from the same geographical area and representative of the wine elaboration, were analysed.
authors.affiliation: Departamento de Quimica Analitica, Universitat de Valencia, 46100-Burjassot,Valencia, Spain.
authors.forename: M C
authors.initials: MC
authors.lastname: Pascual-Martí
authors.forename: A
authors.initials: A
authors.lastname: Salvador
authors.forename: A
authors.initials: A
authors.lastname: Chafer
authors.forename: A
authors.initials: A
authors.lastname: Berna