Extraction and purification method of anticoagulant from hemendary gillian leech

摘要

Applicant has isolated a Factor X.sub.a inhibiting substance from the salivary gland extract of the leech H.ghilianii. The extract is subjected to separation using both DEAE-cellulose and heparin-agarose chromatography resins eluting with an increasing salt gradient. The extract is subjected to affinity chromatography using Factor X.sub.a bound to an Affi-Gel-15 resin eluting with HEPES containing benzamidine. Reverse phase chromatography yields several purified peptides or proteins having Factor X.sub.a inhibiting activity. The properties and clinical compositions of these FX.sub.a inhibitors are described.