Chemical comparison of Astragali Radix by UHPLC/Q-TOF-MS with different growing patterns

Astragali Radix (AR) is commonly used as the herbal drug in the traditional Chinese medicine. In this study, cultivated AR (AR-C) and wild/semi-wild AR (AR-W) were compared by ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS). With the help of multiple mass defect filter (MMDF) and the Global Natural Products Social Molecular Networking (GNPS), chemical investigation of the AR led to the tentative annotation of 196 compounds, including 76 isoflavones and flavones, 50 isoflavanes and pterostanes, 44 saponins, and 26 other compounds. Further analysis showed that 55 compounds (17 isoflavones and flavones, 25 isoflavanes and pterostanes, 8 saponins, and 5 others) showed higher contents in the AR-W. There were 13 compounds showed FC values higher than 3, and further ROC analysis showed 1 of them could be used as the marker for discrimination of AR-C and AR-W. We also found that isoflavanes, pterostanes, and isoflavones were more likely to be substituted by malonyl groups than the flavones and astragalosides, and the sum of malonyl-substituted flavonoid glycosides and corresponding precursor were also higher in AR-W than AR-C. However, the correlation between the chemical difference and the pharmacological difference is needed in the future studies.

Automated summary

This study compared cultivated Astragali Radix (AR-C) and wild/semi-wild Astragali Radix (AR-W) using ultra-high-performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry. Chemical investigation of Astragali Radix led to the tentative annotation of 196 compounds, and further analysis showed that 55 compounds had higher contents in the wild/semi-wild Astragali Radix. Thirteen compounds showed FC values higher than 3, and one of them could be used as a marker for discrimination of AR-C and AR-W. The study also found differences in the substitution of certain compounds between the two types of Astragali Radix.