Study on the Technology of Extraction and Purification of Tea Polyphenols and EGCG

Four kinds of different methods was used to extract the tea polyphenols (TP) and epigallocatechin gallate (EGCG) from the fresh old age tea leaves. The extraction liquor obtained under the optimal conditions was further purified by membrane filtration, resins absorption and column chromatographic exctration (CCE). The results indicated that the concentrations of TP and EGCG respectively increased to 96.1% and 60.5% after separated by the hollow fiber membrane and resins absorption. And then, after the separation by silica gel CCE method, the EGCG concentration was more than 98%.