Biosynthesis and Translocation of Diosgenin in Costus speciosus

Abstract

Summary Radio-actively labelled free and conjugated diosgenin was isolated from different parts such as stem, leaf, seeds, flowers, and rhizomes of Costus speciosus after feeding 14C mevalonate, diosgenin, and diosgenin glycoside through different parts in separate sets of experiments. Percent distribution of radioactivity in various parts of the plant suggested: (a) diosgenin is biosynthesised in leaves and then translocated to all the parts of the plant. (b) glycosidation of diosgenin takes place in all the parts of the plant and diosgenin glycosides are stored in rhizomes, seeds, and flowers. (c) deglycosidation of saponin was observed only in the rhizomes indicating that some enzyme is present in the rhizome which is responsible for the hydrolysis.