QUANTITATIVE DENSITOMETRIC EVALUATION OF HARPAGOSIDE IN THE SECONDARYROOTS OF HARPAGOPHYTUM-PROCUMBENS DC

Harpagophytum procumbens D.C. (Devil's Claw) secondary roots are used in Europe as a home remedy for lack of appetite, dyspeptic complaints, and in supportive therapy for degenerative disorders of the locomotor system, The main characteristic iridoid glucoside of the plant is har pagoside. An HPTLC method has been developed for the quantitative dete rmination of harpagoside in the secondary roots and extracts of this p lant. The mobile phase used is an optimized version of one described i n the literature; it furnished the most homogenous spots for quantitat ive densitometric evaluation (at lambda = 286 mn, the wavelength of ma ximum absorption of harpagoside). The results have been compared with those obtained after visualization with sulfuric acid - vanillin reage nt and those obtained using a previously published HPLC method, To che ck that separation was complete, the spectra of harpagoside obtained f rom Devil's Claw extracts before and after visualization were superimp osed on those of harpagoside standard.