Abstract

Tannins, phlobatannins, saponins, flavonoids, terpenoids, cardiac glycosides and alkaloids distribution in Coleus forskohlii belonging to the family Lamiaceae a well known medicinal plant in India was examined. Qualitative analysis carried out on this plant shows that terpenoids, tannins, flavonoids, phlobatannins, saponins and cardiac glycosides were present in C. forskohlii. The phytochemical constituents with respect to the role of this plant in traditional medicine treatment have well been established. Forskolin, a diterpene compound is the active principle of the C. forskohlii. Histochemical test was done to locate the forskolin in roots and tubers of C. forskohlii. Forskolin was found in the cells of cork, cortex, medullary rays and xylem in roots and tubers of C. forskohlii. These yellowish and reddish-brown masses are of diagnostic importance for this drug plant and can be used for its characterization.

Key words: Coleus forskohlii, phytochemical constituents, forskolin, histochemical localization.