A comprehensive untargeted characterisation strategy for discriminating the geographical origins of Astragali Radix, integrating mass spectrometry data, molecular networking, and collision cross section measurements with chemometric analysis

Astragali Radix is renowned for its dual use in medicine and food. This study presented a comprehensive approach that combines ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry, in-house library matching, fragment ion identification, molecular networking and collision cross section prediction to assess Astragali Radix quality. Based on this approach, 130 compounds were successfully characterised, categorised into 38 saponins, 68 flavonoids, 10 amino acids, 5 organic acids, and others. Additionally, 8 pairs of isomers were verified based on collision cross section measurements. Furthermore, Astragali Radix produced in the Gansu, Shanxi and Jilin provinces could be successfully discriminated using PLS-DA and OPLS-DA models. Twenty differential metabolites were identified including 8 flavonoids and 12 saponins such as astragaloside II, neoastragaloside I, astragaloside VII, astragaloside VI, soyasaponin I, calycosin-7-O- glucoside, formononetin-7-O-glucoside-6”-O-acetate, and ononin, which could be used as potential markers.