GREEN TEA EXTRACT IM ANTITHROMBOTIC AGENT AND A PROCESS FOR PREPARING THE SAME

摘要

Extracts of green tea useful as antithrombotic agent based on catechins in its leaves is provided. Dried leaves of green tea are extracted in hot water or mixture of water and lower alcohols. Extracting solution is filtered to remove insoluble substances. Filtrates obtained is concentrated at 50-70 deg.C for 30 mins-2 hrs under the reduced pressure. Concentrates is extracted repeatedly in ethylacetate to obtain the organic solvent layor and then separated it by column chromatography using mixture of water and acetone, dioxane, methanol or isopropanol as separating solvent. Solution separated is freeze-dried to give green tea extracts powder whose component is polyphenols 25-30%, epigallocatechin gallate 40-70%, mixture of epicatechin and epigallocatechin 0-35%.