Systematic study of beta-asarone-rich volatile oil from Acori graminei rhizoma by off-line supercritical CO2 extraction-gas chromatography-mass spectrometry

Supercritical CO2 extraction (SCE) technology was used to extract a volatile oil, rich in beta-asarone, from Acori graminei rhizoma (AGR). The effect of different extraction and fractionation parameters on oil yield and selectivity towards beta-asarone was investigated by SCE using commercial AGR samples. The optimal conditions (P(e)/T(e) = 10 MPa/45 degrees C; P(f1)/T(f1) = 8 MPa/-10 degrees C; P(f2)/T(f2 )= 2 MPa/10 degrees C) gave a good oil yield and selectivity for beta-asarone. The extracts were also analyzed by GC-MS and compared with the volatile oil obtained by hydrodistillation, in which 39 main constituents including beta-asarone were found. Different cultivated AGR samples obtained from three areas of China were evaluated in terms of their volatile oil compositions obtained by extraction of commercial AGR samples under optimal conditions; the extract of the Guangdong (GD) sample showed a high beta-asarone content.