Asian Journal
Of Traditional Medicines

Abstract: It is of great importance to establish systematic quality control methods for the effective fractions of herbal medicines as part of the modernization programme for Traditional Chinese Medicines. The effective fraction from Dioscorea spongiosa and its major active component, methyl protodioscin, have been reported to have antiosteoporotic activity. In the present study, the quantitative analyses of the total saponins and methyl protodioscin of the effective fraction from Dioscorea spongiosa were established by vanillin-perchloric acid colorimetry and HPLC, respectively. The content of total saponins in three batches of effective fractions, determined by colorimetry with methyl protodioscin as the reference substance in this study, was more than 55%. The established HPLC method, which has good linearity, precision, and reproducibility as well as being highly stable and sensitive, is practical and reliable for the quality control of Dioscorea spongiosa. The combination of both methods may be also helpful for the effective fractions of other species of Dioscorea in terms of their systematic evaluation and quality control.

Key words: Dioscorea spongiosa, effective fraction, methyl protodioscin, total saponins, colorimetry, HPLC, quality control