RHIZOMA GASTRODIAE PLANT EXTRACT USED TO PREVENT AND TREAT ALZHEIMER DISEASE AND VASCULAR DEMENTIA AND MIXED TYPE DISEASES THEREOF AND PREPARATIVE METHOD THEREOF

摘要

The present invention discloses use of Rhizoma Gastrodiae plant extract containing parishin derivative in manufacture of medicaments for preventing and treating Alzheimer disease (AD), vascular dementia (VaD) and mixed type diseases thereof. The present invention also discloses the method for extracting and refining plant extract from Rhizoma Gastrodiae (Gastrodia elata Blume), wherein the effective constituent is parishin derivative, especially parishin A, B, C. The plant extract which is extracted by water or alcohol-water and refined and purified by chromatography contains parishin derivative whose content is more than 35%, especially more than 50%. The dosage forms of the present invention preferably include injection, tablets, capsules, soft capsules, oral liquid or drop pills etc.