DIFFERENTIAL-PHOTOMETRIC ESTIMATION OF CHOLESTEROL AND SITOSTEROL IN THE PRESENCE OF CERTAIN OTHER 3β-HYDROXYSTEROLS

Publisher Website
Google Scholar
Abstract
Material differences in the extinction coefficients of cholesterol and sitosterol (β- and γ-isomer) in the Liebermann-Burchard reaction contrast with the fact that the extinction coefficients of these sterols are identical in the Tschugaeff reaction. This forms the basis for the quantitative differentiation between these sterols by mathematical treatment of data obtained in the two reactions. The principles involved form an extension of analytical steps reported elsewhere for the estimation of 7-dehydrocholesterol, Δ7-cholestenol, and coprostanol.When the concentrations of these five sterols have been determined in faeces excreted by subjects subsisting on formula rations high in corn oil, an estimate of cholestanol plus stigmastanol may be obtained by subtracting the sum of their concentrations from the value for total 3β-hydroxysterol, as determined by the anthrone procedure.Recoveries were as follows: cholesterol, 100.7 ± 7.9%; sitosterol isomers, 99.1 ± 7.6%; cholestanol and (or) stigmastanol, 90.4 ± 10.1%.