Variation of chemical constituents in processed licorice roots: Quantitative determination of saponin and flavonoid constituents in bark removed and roasted licorice roots

As a continuing study of chemical characterization of crude drug processing , we have been analyzing the chemical constituents in licorice roots before and after processing. At first, we analyzed chemical constituents in licor ice roots of various origins. Next, we have developed the HPLC analytical m ethod, by which saponins and flavonoids, major constituents in various lico rice roots, were determined simultaneously in a quantitative manner. In this paper, by means of the HPLC analytical method, chemical constituent s in licorice roots, processed and unprocessed, were determined. It was fou nd that nonglycosidic flavonoid constituents were mostly lost while root ba rk removing, whereas, in roasted licorice roots, sugar chains in the saponi n and glycosidic flavonoid constituents were hydrolyzed stepwise during roa sting through hydrothermolysis.