title: Identification of α-tocotrienolquinone epoxides and development of an efficient molecular distillation procedure for quantitation of α-tocotrienol oxidation products in food matrices by high-performance liquid chromatography with diode array and fluorescence detection.
abstract: The aim of this study was to investigate the most important oxidation products of α-tocotrienol (α-T3) along with other tocochromanols in lipid matrices and tocotrienol-rich foods. For this purpose, an efficient molecular distillation procedure was developed for the extraction of analytes, and α-T3-spiked and thermally oxidized natural lipids (lard and wheat germ oil) and α-T3-rich foods (wholemeal rye bread and oil from dried brewer's spent grain) were investigated through HPLC-DAD-F. The following α-T3 oxidation products were extractable from lipid matrices along with tocochromanols: α-tocotrienolquinone (α-T3Q), α-tocotrienolquinone-4a,5-epoxide (α-T3Q-4a,5-E), α-tocotrienolquinone-7,8-epoxide (α-T3Q-7,8-E), 7-formyl-β-tocotrienol (7-FβT3), and 5-formyl-γ-tocotrienol (5-FγT3). Recovery rates were as high as 88% and enrichment factors up to 124. The proposed method allows the investigation of α-T3Q, α-T3Q-4a,5-E, α-T3Q-7,8-E, 7-FβT3, and 5-FγT3 in small quantities (<0.78 μg/g) in lipid matrices, which is necessary for the investigation and analysis of the formation kinetics of these oxidation products in fat, oils, and tocotrienol-rich foods.
authors: Department of Analytical Chemistry, Institute of Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover , Foundation, Bischofsholer Damm 15, D-30173 Hannover, Germany.
authors: Anne
authors: A
authors: Büsing
authors: Astrid M
authors: AM
authors: Drotleff
authors: Waldemar
authors: W
authors: Ternes
mesh_terms: D001939:Bread / Q000032:analysis; D005591:Chemical Fractionation / Q000379:methods; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D057168:Distillation; D004852:Epoxy Compounds / Q000032:analysis; D005453:Fluorescence; D005504:Food Analysis / Q000379:methods*; D008055:Lipids / Q000737:chemistry; D010084:Oxidation-Reduction; D010938:Plant Oils / Q000032:analysis; D015203:Reproducibility of Results; D024508:Tocotrienols / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification; D014451:Ubiquinone / Q000031:analogs & derivatives / Q000032:analysis
chemical_list: D004852:Epoxy Compounds; D008055:Lipids; D010938:Plant Oils; D024508:Tocotrienols; D014451:Ubiquinone; C050055:wheat germ oil; C571746:alpha-tocotrienol quinone; C082032:tocotrienol, alpha