(73c) Supercritical Fluid Extraction and Chromatography of Bioactive Nutraceuticals

North American ginseng extracts are complex phytochemical mixtures with ginsenosides as the major biologically active components. There is tremendous interest in examining the phytochemistry and bioactivity of these extracts based on recent commercial products using North American ginseng extract for treating colds and flu (e.g. ColdFX™). This work examined supercritical fluid chromatography (SFC) coupled with an evaporative light scattering detector (ELSD) for separation and identification of ginseng extracts. Supercritical CO₂ extraction method was used for ginsenosides extraction from North American ginseng roots using DMSO as modifier. A cyanopropyl packed column stationary phase was used with a CO₂-based mobile phase containing methanol as modifier. SFC conditions were examined on ginseng extract profiles including pressure (100-200 bar), amount of modifier (5-50%), and the effect of water, acidic (trifluoroacetic acid), and basic (diisopropylamine) additives, integrated into methanol as modifier. The nature of additive have great effect on ginsenosides separation and retention time whereas not all the ginsenosides could elute without the presence of additives. The most effective elution of the six common ginsenosides with the best peak shape were obtained between 10-13 min in the case of using 0.1% acidic additive (trifluoroacetic acid) at a pressure of 150 bar, flow rate of 1.5 ml/min, and mobile phase gradient of 15-31% methanol in CO₂. These results show that SFC is a promising technique for separation and identification of novel extracts.