GB820788A - Extracts of parts of plants of the genus aesculus - Google Patents

Abstract

A saponin free extract of plants of the genus Aesculus, e.g the horse-chestnut tree (Aesculus hippocastanum), which can be injected without haemolytic effects, is prepared from a saponin containing extract of the horse-chestnut tree by removing the saponins without removing the other substances by (a) treatment with finely divided solid cholesteral, which forms an addition compound insoluble in the extraction solvent, or (b) extraction with a water-immiscible solvent, e.g. chloroform, a halogen containing hydrocarbon, an aliphatic alcohol containing not more than 8 C. atoms, e.g. amyl alcohol, or a mixture thereof. The cholesterol may be in the form of an aqueous suspension or emulsion and is preferably used in excess. It is preferred to carry out the reaction at elevated temperature while the extraction solvent is continuously being removed in vacuo. The precipitate of saponin-cholesterol is removed and the cholesterol may be recovered for re-use by treatment with glacial acetic acid or extraction with trichlorethylene. In the extraction process (b), the pH of the extract is reduced to below pH 4.5, and preferably 1 to 3, by acid especially hydrochloric and after the removal of the saponin solution, the residual extract is adjusted to pH 6.0 by means of sodium hydroxide. The extract so produced contains, inter alia, and when suitably diluted with water may be injected. It is preferred to extract an aqueous alcoholic solution of horse-chestnut seeds containing not more than 50% alcohol, and especially 36% ethyl alcohol, with chloroform. Specification 820,787 is referred to.