GB890207A - Extraction of a new polysaccharide substance from crude fucoidin - Google Patents

Abstract

The invention comprises a polysaccharide comprising a fucosemethylpentose ether sulphate polymer having a molecular weight of about 5,000 to about 50,000, a specific rotation of [a ]25D = -119,6 DEG in water, having in aqueous solution of 0,8% strength an ultra-violet absorption of very weak character in the range 256-280mm and being devoid of additional absorption maxima at 220-600 mm , having in 0,85 saline solution a relative viscosity of 1,2 being amorphous in character, containing the elements carbon, hydrogen, oxygen, sulphur, sodium, potassium and calcium, and being soluble in water. The novel polysaccharide is obtained by fractional precipitation of an aqueous solution of crude fucoidin by means of a water-miscible organic solvent and collecting the polysaccharide precipitated as the concentration of the solvent in the solution is increased from about 45% to about 67%, or by treating the said aqueous solution with a quaternary ammonium compound, preferably one containing a carbon chain of 8 carbon atoms or more, collecting the water-insoluble precipitate, breaking up the obtained quaternary ammonium-polysaccharide complex by the addition of a strongly ionizable salt and collecting the polysaccharide from the obtained solution with a water-miscible organic solvent. Both the fractional precipitation method and the quaternary ammonium complex formation may be used. The new polysaccharide may be further purified by dialysis. The product possesses anticoagulant and antilipemic activity. An example also describes the extraction of crude fucoidin from ground, air-dried Fucus vesiculosus by heating with water, adding toluene, diluting and filtering the supernatant fluid, adding lead acetate solution and filtering, adding barium hydroxide to the filtrate, shaking the resultant precipitate with sulphuric acid, and dialysing for 3 days. The non-dialysable material is concentrated in vacuo, freed of insoluble material by spinning at 12,000 g. for 45 minutes, the supernatant is poured into ethanol and dried in vacuo over P2O5. The material is designated as crude fucoidin.ALSO:A new polysaccharide comprising a fucosemethylpentose ether sulphate polymer (obtained from crude fucoidin, see Group IV (a)) having anticoagulant and antilipemic properties, may be dispersed in any of the usual dosage unit forms of pharmaceutical preparations, for example, tablets, pills, capsules, solutions, powders, with any desired excipients, binders, fillers or other therapeutically inert ingredients. For parenteral administration, the polysaccharide may be dissolved in any suitable liquid medium which is compatible with body fluids, e.g. physiological saline solution. For oral administration, the polysaccharide may be employed with or without other physiological active ingredients in tablets, pills or capsules.