METHOD OF ISOLATING HIGH PURITY EPIGALLOCATECHIN GALLATE FROM GREEN TEA EXTRACT

摘要

PURPOSE: A method of isolating high purity Epigallocatechin gallate (EGCg) from a green tea extract is provided to commercially mass-produce high purity EGCg of 90% or more for the use in natural anti-oxidants and skin care cosmetics. CONSTITUTION: In a method of isolating EGCg from a green tea extract, a green tea extract aqueous solution and a caffeine aqueous solution are prepared, and mixed with each other at from ambient temperature to 80 deg.C. The mixed solution is standing at a light-intercepted area at 0-10 deg.C for two or more hours to form a precipitate. The precipitate is isolated from the upper-leveled liquid to form a precipitate aqueous solution. Oxide is added to the precipitate aqueous solution, and heated. A caffeine content is isolated from the precipitate aqueous solution using halogenated organic solvent. The caffeine-removed precipitate aqueous solution is loaded in a column charged with adsorbents. An eluate of alcoholic aqueous solution is applied to the target solution to elute high purity EGCg aqueous solution therefrom.