An improved extraction procedure for the rapid, quantitative high-performance liquid chromatographic estimation of the main eleutherosides (b and e) inEleutherococcus senticosus (eleuthero)

Eleutherosides were extracted with aqueous methanol and analysed by reversed-phase high performance liquid chromatography on a C-18 column. Recovery was better than 80% for eleutheroside B within the concentration range 500 to 10,000 μg, and similarly for eleutherosides E in the range 500 to 2,500 μg. Lower recovery values were obtained at higher concentrations for eleutheroside E due to its insolubility in alcoholic solutions. The use of trifluoroacetic acid solution in methanol was found to resolve the solubility problem. The concentration ranges over which a linearity of response for both eleutherosides could be validated were improved significantly by this adjustment.