| EGCG(epigallocatechin-3-gallate) is the highest catechin content and most important physiological activity substance in tea quality , it plays a crucial important role on several biology functions. EGCG3 " Me and EGCG4" Me are two O-Methylated EGCG derivatives, structural formula are (-)-epicatechin-3-O-(3-O-Methyl) gallate and (-)-epicatechin-3-O-(4-O-Methyl) gallate respectively. They have been observed significance efficacy on an anti-allergic action, especially on anti-pollen-allergic action.As research shows in Japan , O-Methylated EGCG may inhibit IgE receptor, which is a major allergic response receptor in the cells. This effect has also been found in the human basophilic cells. Human basophilic cell is a blood one which release histamine. O-Methylated EGCG has more inhibitory effect on histamine releasing than EGCG. A lot of biology functions have been proved in vitro and in vivo clinic experiments. In Japan , About one - third Japanese are taken various degrees of pollen-allergic action. So this research is paid great attention in Japan. while, there is little research report on O-Methylated catechin in china, relevant research has not been found in the newspaper.This research chooses some primary tea plant varieties growing in south-west China and some wildgrowing tea plants resources as experiment samples, Using HPLC to analyze O-Methylated EGCG content of samples, and screen out some higher O-Methylated EGCG content tea plant varieties and resourses. And then, through a series of processing studies, some external and internal factors which are related to the content of O-Methylated EGCG were opened up. This research results as follows:1,Through tea plant varieties investigations and studies, it finds that middling-blade-profile variety has higher content of EGCG3"Me (such as No.42 = 0.77% ,No.51 = 1.38% ,No.55 = 0. 94% and so on, in the west tea plant varieties which are planted widely, No.58 has the highest EGCG3 " Me content, (the content is 1.03%), in the small-leaf varieties, the content of EGCG3" Me take second place, while in the large-leaf varieties, such as Yunan large-leaf variety, it has lowest content of EGCG3"Me ,even nothing.2,In the 69 tea plant varieties which are analysized, Altogether there are 19 tea plant varieties owning EGCG4 " Me, only taking 27.5% among all resourses. Thereinto, the highest content is 0.22%, the lowest one is only 0.06%.3,In the same time, different area's entironment effect on the content of EGCG3 " Me are remarkable, No.55 and No.3 are the same tea plant varieties, but they grow on different areas, No.55 is planted on Chongqing er'sheng tea garden, No.3 is Wumaping ones. The content of EGCG3 " Me are 0.94% and 0.38 % respectively, ratio is 2.47:1, No.58 and No.26 are also the same tea plant variety, respectively grow in Sichuan tea Research Institute and Wumaping tea garden, The content of EGCG3" Me are 1.03 % and 0.34% respectively, ratio is 3.03:1, it shows that lower altitude and higher illumination are very important to compound of O-Methylated EGCG.4, As the leaves degree of maturity improving, the content of EGCG3 " Me in tea increase step by step, when arriving at a definite maturity, the content of cellulose in tea has also increased, Gradually, the content of catechin steadily decreases. Research found: the content of EGCG3" Me is the most in one bud three leaves, and the content of EGCG3 " Me in one bud two leaves is as much as in one bud four leaves, lower 10% than in one bud three leaves, while there is little EGCG3 " Me in the stem.5, As withering time expanding , the content of EGCG3" Me Gradually increases, when the withering time reaches 8h, EGCG3 " Me may reach its top content, afterwards, as the withering time longer ,the content of EGCG3 " Me decreases step by step, when the time arrives at 18h., the content has a half compared with non-withering state.
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