STUDIES ON THE CHEMICAL ISOMERIZATION OF VITAMIN D

Abstract

Gas chromatography for the identification of vitamin D2, 5,6-trans vitamin D2, isocalciferol (isovitaminD2), isotachysterol2, tachysterol2, lumisterol2 and ergosterol was investigated, applying the following conditions: apparatus, a Shimazu GC-1B Gas Chromatograph with hydrogen flame ionization detector; column, U-shaped stainless steel tube (0.4 x 75 cm) packed with silianized 60- to 80-mesh Gas-Chrom W coated with 1.5% SE-30; column temperature, 220[degree]; vaporizer temperature, 250[degree] to 260[degree]; detector temperature, 220[degree]; nitrogen gas flow, 90 to 120 ml/min. Lumisterol2 from thermal cyclization products of vitamin D2 (pyro- and isopyro- calciferol), formed during the gas chromatography, 5,6-trans vitamin D2 from isocalciferol and isotachysterol2 from tachysterol2 were not separated. Therefore, the identification of these compounds was impossible by applying gas chromatography alone.