Two major isoflavone glycosides [calycosin 7-O-β-D-glucopyranoside （1） and ononin （2）] and their aglycones [calycosin （3） and formononetin （4）] were simultaneously quantified with HPLC/DAD method. Two unknown compounds were identified as calycosin 7-O-β-D-glucopyranoside-6＇＂-O-malonate （U1） and formononetin 7-O-β-D-glucopymnoside-6＇＂-O-malonate （U2）, respectively, with LC/MS^n. Raw Radix astragli were shown to have higher contents of isoflavone glycosides （1, 2）, but lower contents of aglycones （3, 4） than the processed herbal materials. After being moistened with water and stored up for 24 h at 35 ℃, the glycosides and their m_alonates were almost completely transformed to their corresponding aglycones. The different contents of the isoflavone glycosides and their aglycones in raw and processed Radix astragali materials might be due to enzymolysis of the glycosides during processing.
