Characterization of hydroxyaromatic compounds in vegetable oils by capillary electrophoresis with direct injection in an oil-miscible KOH/propanol/methanol medium.
The separation of hydroxyaromatic compounds in vegetable oils, including synthetic antioxidants (3-tert-butyl-4-hydroxyanisol and 2,6-di-tert-butyl-4-hydroxytoluene), E-vitamers and other natural oil components, by nonaqueous capillary electrophoresis in an oil-miscible background electrolyte (BGE) was investigated. The BGE contained 40 mM KOH in a methanol/1-propanol (PrOH) mixture (15:85 v/v). The oil samples were 1:1 diluted with PrOH and directly injected in the capillary. Under negative polarity (cathode at the injection end), the anionic solutes moved faster than the electroosmotic flow, being well-resolved among them and from the triacylglycerols. Using virgin palm, extra virgin olive, wheat germ, virgin soybean and other oils, the capability of the procedure to quickly yield a characteristic profile of the biophenols present in the sample was demonstrated. The alpha-, (beta + gamma)- (as unresolved pair) and delta-tocopherols of a soybean oil sample were quantified.
Mendonça
Carla R B
CR
Departament de Química Analítica, Universitat de València, Burjassot, Spain.
Bica
Clara I D
CI
Piatnicki
Clarisse M S
CM
Simó-Alfonso
Ernesto F
EF
Ramis-Ramos
Guillermo
G
D000433:1-Propanol / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods*; D006878:Hydroxides / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D010938:Plant Oils / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D012995:Solubility
D006878:Hydroxides; D010636:Phenols; D010938:Plant Oils; D017680:Potassium Compounds; D000433:1-Propanol; C029943:potassium hydroxide; D000432:Methanol