An efficient combination of supercritical fluid extraction and high-speed counter-current chromatography to extract and purify (E)- and (Z)-diastereomers of a-asarone and ß-asarone from Acorus tatarinowii Schott

In this study, supercritical fluid extraction (SFE) was used to extract essential oil from Acorus tatarinowii Schott under the pressure of 25MPa and temperature of 35 degrees C. Two (E)- and (Z)-diastereomers of a-asarone and beta-asarone were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of n-hexaneethyl acetatemethanolwater (1:0.2:1:0.3, v/v). The separation yielded a total of 39 mg of alpha-asarone and 463 mg of beta-asarone from 1.0 g of essential oil in one-step separation with the purity of 98.9 and 99.1%, respectively, as determined by HPLC. The chemical structures of these compounds were identified by EI-MS, 1H-, and 13C-NMR.