Comparing extraction methods to recover ginseng saponins from American ginseng (Panax quinquefolium), followed by purification using fast centrifugal partition chromatography with HPLC verification

A series of experiments were carried out to compare the extraction of ginseng saponins, ginsenosides, from powdered American ginseng (Panax quinquefolium) using pressurized hot water and the more conventional ultrasonic-assisted extraction. Three solvents were tested, water, n-butanol-saturated water, and water-saturated n-butanol. Each resulting extract was further purified using fast centrifugal partition chromatography (FCPC) in order to better quantify the contents of the crude plant extract. The pressurized hot water system extracted a greater yield of saponins, 11.2 mg/g (extraction at 110 °C and 440 kPa), than the ultrasonic-assisted method, 7.2 mg/g (extraction at variable temperature with no external pressure). The difference in solvent system for either extraction methods was not significant, and the results gave credence for the use of water as the extraction solvent. n-Butanol-saturated water yielded the most saponins (10.1 mg/g), while water yielded 9.8 mg/g, and water-saturated n-butanol yielded 7.8 mg/g. Since water is an environmentally benign solvent, this result is quite attractive for future work.