Uptake of [2-(14)C] mevalonic acid by lipid and glycoside sterols

D. L. [2-(14)C] mevalonic acid was fed to Digitalis purpurea flowering plants and the 4-4'-dimethyl and phytosterol fractions isolated at time intervals from the glucoside and lipid portions of the plant extract. The incorporation of mevalonic acid was determined in both the aerial parts and the roots over a period of 35 days. In the aerial parts the uptake of radioactivity was rapid in the cycloartenol and lipid phytosterol fractions, but less so in the glucoside phytosterols. In the roots the glucoside phytosterols incorporation of label was considerably more rapid than in the lipid fraction.