Colour, chemical compounds, and antioxidant capacity of Astragali Radix based on untargeted metabolomics and targeted quantification.

The colour parameters, chemical compounds, and antioxidant capacity among the different transverse sections of secondary xylem and phloem varied. The yellow colour of secondary xylem was correlated to high flavonoid content and antioxidant activity, and well-defined type A of Astragali Radix had better quality than other types.