title: Simultaneous determination of tocopherols and tocotrienols in hazelnuts by a normal phase liquid chromatographic method.
abstract: A normal-phase high-performance liquid chromatography (NP-HPLC) method for the determination of tocopherols and tocotrienols in hazelnuts is reported. Three extraction procedures (with and without saponification) were assayed; the best results were obtained with a simple solid-liquid extraction procedure. Chromatographic separation was achieved using an Inertsil 5 SI column using isocratic elution with hexane/1,4-dioxane (95.5:4.5, v/v) at a flow rate of 0.7 mL/min. The effluent was monitored by a series arrangement of a diode-array followed by a fluorescence detector. All compounds were separated in a short period of time (17 min). The method proved to be rapid, sensitive, reproducible and accurate, allowing the simultaneous determination of all vitamin E homologues.
authors.affiliation: REQUIMTE, Serviço de Farmacognosia, Faculdade de Farmácia, Rua Anibal Cunha, 164, 4099-030 Porto, Portugal. jamaral@ipb.pt
authors.forename: Joana S
authors.initials: JS
authors.lastname: Amaral
authors.forename: Susana
authors.initials: S
authors.lastname: Casal
authors.forename: Duarte
authors.initials: D
authors.lastname: Torres
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Seabra
authors.forename: Beatriz P P
authors.initials: BP
authors.lastname: Oliveira
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D031211:Corylus / Q000737:chemistry*; D012680:Sensitivity and Specificity; D024505:Tocopherols / Q000032:analysis*; D024508:Tocotrienols / Q000032:analysis*
chemical_list: D024508:Tocotrienols; D024505:Tocopherols