GB832017A - Senna preparations - Google Patents

Abstract

An extract of senna is prepared by extracting senna leaf or pod (with or without seed) with an aqueous organic solvent and adding to the separated liquid extract a metal salt and an anhydrous organic solvent to cause precipitation of a water-soluble product comprising the active principles of senna in intimate association with the metal ion of the salt. The product may be further treated to remove metal ions, e.g. by precipitation with an organic acid, e.g. oxalic acid, or by means of a strongly acid ion exchange resin. The product freed from metal ions may be further purified, e.g. by chromatography to give a stable crystalline product. The aqueous organic solvent may be water and ethanol, acetone or isopropanol (50 to 80%, preferably 70% v/w.) and may also contain an organic acid. The anhydrous solvent may be ethanol, acetone or isopropanol and the metal salt is preferably one of an alkaline earth metal, e.g. calcium. The product may be incorporated in conventional pharmaceutical forms, e.g. tablets, pills, capsules, cachets, chocolate, chewing gum, pastilles, lozenges, granules, suppositories, enemas, syrups, elixirs or injections, alone or with other therapeutic agents.