Figure 2.
High-performance liquid chromatography (HPLC) analysis of ginger supercritical fluid extraction (SFE-CO2) extracts and radix aucklandiae ethanol extracts. (a) HPLC chromatogram of 6-gingerol standard. (b) HPLC chromatogram of the ginger SFE-CO2 extract sample, the retention time of 6-gingerol was 13.464 min. (c) HPLC chromatogram of costunolide and dehydrocostus lactone standard. (d) HPLC chromatogram of the radix aucklandiae ethanol extract sample, the retention time of costunolide and dehydrocostus lactone were 15.434 and 17.535 min, respectively