Patent FR-2926994-A1 (FR)
Title: Preparing extract, to treat e.g. dementia, comprises extracting Ginkgo biloba leaves with acetone, separating major part of the solvent, diluting aqueous solution with water, adding ammonium sulfate and extracting with methylethylketone
Inventor: TENG BENG POON
IPC: A61K36/16
Filed: 2008-02-06
Abstract: Preparing an extract comprises (a) extracting Ginkgo bilobaleaves with e.g. aqueous acetone; (b) separating major part of the organic solvent from the extract; (c) diluting the remaining concentrated aqueous solution with water; (d) adding ammonium sulfate to the remaining aqueous solution and extracting the formed solution with methylethylketone; (e) concentrating the obtained extract; (f) adding an aqueous solution of a lead salt to the obtained solution; and (g) extracting the remaining aqueous alcoholic solution with an aliphatic or cyclophatic solvent. Preparing an extract of Ginkgo bilobaleaves, comprises (a) extracting Ginkgo bilobaleaves at a temperature of approximately 40-100[deg] C, with aqueous acetone, 1-3C aqueous alcohol or anhydrous methanol; (b) separating major part of the organic solvent from the extract containing up to 10 wt.%, so that the water is added during final stages of distillation; (c) diluting the remaining concentrated aqueous solution with water to obtain a content of solid materials of 5-25 wt.%, allowing to cool by stirring, at a temperature of below25[deg] C, until to form a precipitate, where the resulting precipitate comprises lipophilic components, which does not dissolve well in water, and is separated; (d) adding ammonium sulfate to the remaining aqueous solution and extracting the formed solution with a methylethylketone or a mixture of methylethylketone and acetone; (e) concentrating the obtained extract to a solid material content of 50-70% and diluting the obtained concentrate diluted with water and ethanol to obtain a solution containing 50 wt.% of water and 50 wt.% of ethanol with a content of solid materials of 10 wt.%; (f) adding an aqueous solution of a lead salt to the obtained solution until a change in the brown color to amber color occurs, and separating the formed precipitate, in which a polyamide is used instead of a lead salt; (g) extracting the remaining aqueous alcoholic solution with an aliphatic or cyclophatic solvent with a boiling point of 60-100[deg] C for separating more alkylphenol compounds; (h) concentrating the remaining aqueous alcoholic solution under reduced pressure to a maximum ethanol content of approximately 5%, and adding ammonium sulfate (up to 20 wt.%); (i) extracting the obtained solution with a mixture of methylethylketone and ethanol in a ratio of 8/2 to 5/5, preferably 6/4; (j) concentrating the resulting organic phase to a solid material (50-70 wt.%); (k) adding ethanol (at least 80%) to the obtained concentrate, then cooling at a maximum temperature of 12[deg] C for at least two hours and eliminating the insolubles by filtration and recovering the filtrate; (l) concentrating the filtrate and drying under reduced pressure at a maximum temperature of 60-80[deg] C to obtain a dry extract with a water content of less than 5%, where the process comprises an additional step, which consists to pass an organic phase obtained in one of steps d, i or k, on an adsorbent having a specific surface of greater than 1000 m 2>/g. An independent claim is included for the Ginkgo bilobaextract substantially devoid of persistent organic pollutants, obtained by the process. ACTIVITY : Cardiovascular-Gen.; Nootropic. MECHANISM OF ACTION : None given.