Investigation on the marker substances of crude drugs in formulations. II.Marker substances for the identification of Cistanchis Herba in drinkable preparations

There are few reports about marker substances for the identification of Cis tanchis Herba in formulations. First, constituent analysis was performed by HPLC for screening of a marker substance, using several lots of Cistanchis Herba and its fluid extract. As a result, two components were clearly dete cted, which were thought to be good marker substances and identified to be echinacoside and acteoside by structural analysis. Stability testing of the se two marker substances in various pH and temperature conditions was carri ed out, which suggested that they are stable and suitable enough for the id entification. Therefore, the identification methods of Cistanchis Herba and its fluid extract in formulations were investigated using five different k inds of commercial drinkable preparations with authentic standard of echina coside and acteoside as marker substances. Consequently, echinacoside and a cteoside were clearly detected in all formulations investigated, using an H PLC-photodiode array detector system. Echinacoside and acteoside will be su ccessfully used as marker substances for the identification of Cistanchis H erba and its fluid extract in formulations.