Characterization of metabolites in Saposhnikovia divaricata root from Mongolia

Saposhnikoviae Radix (SR), derived from the dried root and rhizome of Saposhnikovia divaricata, is a popular crude drug used in traditional Chinese and Japanese medicine. To evaluate the metabolites of S. divaricata roots from Mongolia and to investigate their geographical variation, we developed the HPLC method, determined the contents of 9 chromones and 4 coumarins, and conducted multivariate statistical analysis. All Mongolian specimens contained prim-O-glucosylcimifugin (1) and 4'-O-β-D-glucosyl-5-O-methylvisamminol (3), and their total amount (5.04-25.06 mg/g) exceeded the criterion assigned in the Chinese Pharmacopoeia. Moreover, the content of 1 (3.98-20.79 mg/g) was significantly higher in the Mongolian specimens than in Chinese SR samples. The specimens from Norovlin showed the highest contents of 1 and 3. The total levels of dihydropyranochromones were higher in the specimens from Bayan-Uul. The orthogonal partial least squares-discriminant analysis revealed that the Mongolian specimens tended to be separated into three groups based on growing regions, in which several chromones contributed to each distribution. Furthermore, ¹H NMR analysis revealed that Mongolian specimens had less amount of sucrose and a substantial amount of polyacetylenes. Thus, in this study, the chemical characteristics of Mongolian S. divaricata specimens were clarified and it was found that the specimens from the northeast part of Mongolia, including Norovlin, had the superior properties due to higher amounts of major chromones.