Analysis and determination of oestrogen-active compounds in fructus amomi by the combination of high-speed counter-current chromatography and high performance liquid chromatography

• HSCCC-estrogenic activity detection applied for screening of estrogenic compounds.
• Eight diarylheptanoids and seven other compounds in fructus amomi were identified.
• Three diarylheptanoids are major constituents of estrogenic activity in fructus amomi.
• Eight diarylheptanoids occupied 0.5% of fructus amomi.
• Fructus amomi is a phytoestrogen food resource rich in diarylheptanoids.

Amomum longiligulare or Amomum villosum showed oestrogenic activity. In the present study, oestrogen-active components in fructus amomi, the seeds of A. longiligulare were separated by high-speed countercurrent chromatography (HSCCC) using stepwise elution of eight mobile phases with gradient polarity and advanced separation by high performance liquid chromatography (HPLC). The results yielded 17 compounds with the amount of 8–138 mg and a purity of 94.3–99.8% from a 3 g ethanolic extract of fructus amomi. The chemical structures of the compounds were identified by ESI-MS and NMR spectra, in which eight diarylheptanoids were demonstrated as the main oestrogen-active compounds in the fructus amomi. Determination of the diarylheptanoids in fructus amomi from various origins showed that fructus amomi contains more than 0.5% total diarylheptanoids. The results showed that fructus amomi is a diarylheptanoids-rich food resource possessing oestrogen-activity. The combination method of HSCCC and HPLC can be applied for the analysis of bioactive compounds by detecting the corresponding bioactivity in the HSCCC fractions and separating the target compounds with HPLC.