HPLC Analysis of Vitamin B_6 Derivatives

Abstract

For the determination of vitamin B_6 derivatives, at least, 6 biologically active vitamers (PL, PN, PM and these phosphate esters) together with pyridoxic acid (PIC), an HPLC system composed of a single reversed-phase ODS column and a highly sensitive fluorescence detector by an isocratic solvent was proposed. Relatively low fluorescence intensity of intact PLP under acidic conditions was improved by converting it to pyridoxic acid 5'-phosphate (PIC-P) in the addition of 5mM KCN at alkaline pH and subsequent heat treatment at 50℃ for 3h. By using the method, the vitamin B_6 contents in some foods and biologically interested materials were analyzed and these data were compared with the data obtained from microbial assay using Saccharomyces cerevisiae ATCC 9080.