Extractions of ginsenosides from ginseng roots with liquid ammonia, methanol-water or water

Extractions of ginsenosides from ginseng roots with liquid ammonia, methano l/water (60:40; v/v) or water were carried out. The extracts have been anal yzed qualitatively and quantitatively to valuate yield and selectivity of e xtractions of ginsenosides. Water supplied the lowest yield. The yields of extracts with liquid ammonia were higher than those with methanol-water (60 %). Yields of the ginsenosides Rb-1, Rb-2, Rc and Rd by extracting with liq uid ammonia are about twice as much as those of the extraction with methpln ol-water (60%). It was proved by HPLC that malonyl-ginsenosides m-Rb-1, m-R b-2, m-Rc and m-Rd were converted to the corresponding neutral ginsenosides by extraction with liquid ammonia. Because of high yields of extracts and simultaneous increase of the contents of Rb-1, Rb-2, Rc and Rd the extracti on with liquid ammonia is obviously superior to the other extraction method s. Furthermore, ginsenosides from ginseng roots were extracted by alkaline met hanol-water (60%) solutions. Alternatively, the extracts of the methanol-wa ter (60%) extraction were treated with sodium hydroxide solution. Both meth ods convert also the malonyl-ginsenosides to neutral ginsenosides.