PRODUCTION OF ESSENCE OF GINKGO BILOBA LEAF

摘要

PROBLEM TO BE SOLVED: To obtain the subject essence having high safety and slight deterioration, useful as a medicine, a food, etc., at an appropriate cost by grinding Ginkgo biloba leaves and subjecting the ground Ginkgo biloba leaves to an operation such as an extraction with dimethyl ether, etc. ;SOLUTION: Ginkgo biloba leaves are ground, extracted by using hydrous dimethyl ether having 7-60% (W/W) water content for extraction in an amount of preferably 5-20 times as much as 1 pt.wt. (dry weight) of Ginkgo biloba leaves preferably at 10-30°C. The extracted solution is separated from an extraction residue to recover an extraction filtrate. In order to precipitate a hydrophobic material from the extraction filtrate, dimethyl ether is evaporated and an aqueous extracted solution is obtained. A precipitate is formed, an aqueous extraction filtrate is separated from the precipitate, recovered and concentrated. An electrolyte is added to the concentrated filtrate, an active ingredient is precipitated, an insoluble fraction is recovered, redissolved in hydrous dimethyl ether and desalted, insoluble substance is separated, the solvent is removed and a powdery essence is recovered by drying to give the objective essence.;COPYRIGHT: (C)2000,JPO