| 摘要 |
PURPOSE:To prepare a purgative by extracting an organic solution of a sennosidecontaining extract with an aqueous medium, thereby limiting the contamination of the purgative with impurities and substances having side effects as low as possible. CONSTITUTION:Rheum powder, which is a known crude drug, is extracted with an aqueous medium. The extract is filtered, residue is washed with water, and the filtrate is added to the washed liquor. A hydrophilic organic solvent (e.g. ethanol, butanol, etc.) is added to the filtrate mixture, dilute sulfuric acid is further added thereto, and the mixture is separated into two phases. Water and dilute NaOH solution are added successively to the organic solvent phase, and the mixture is let to stand still to separate the water phase. The water phase is concentrated in vacuo at 50-55 deg.C. |
