[Investigation on the marker substances of crude drugs in formulations. I. Marker substances for the identification of astragali radix in kampo and drinkable preparations].

There are few reports about marker substances for the identification of Astragali Radix in formulations. First, constituents analysis was performed by HPLC for the screening of a marker substance, using several lots of Astragali Radix and its fluid extracts. As a result of the analysis, one of the main components was clearly detected even in the fluid extracts, and thought to be a good marker substance. This component was identified to be calycosin (7,3'-dihydroxy-4'-methoxyisoflavone) by the structural analysis. Then, the identification methods of Astragali Radix and its fluid extracts in formulations were investigated with an Astragali Radix extract as a reference standard solution and calycosin as a marker substance. This method was applied to three different kinds of Kampo formulations and three different kinds of drinkable preparations. Consequently, calycosin was clearly detected by a HPLC-multi wavelength detector system, in all investigated formulations. Calycosin will be successfully used as a marker substance for the identification of Astragali Radix and its fluid extracts in formulations.