Changes in epigallocatechin-3-O- (3-O-methyl) gallate and strictinin contents of tea (Camellia sinensis L.) cultivar 'Benifuki' in various degrees of maturity and leaf order

We have reported that O-methylated EGCGs (epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3″Me) and epigallocatechin-3-O-(4-O-methyl) gallate) and strictinin had anti-allergic action, and that the tea (Camellia sinensis L.) cultivar 'Benifuki' was rich in EGCG3″Me. However, changes in the content of anti-allergic components in tea leaves during growth are unclear. Therefore, here we determined the contents of EGCG3″Me and strictinin at various points of maturity and in the leaf order of 'Benifuki' tea in the first and second crop seasons. The EGCG3″Me content was high and caffeine content decreased in fully-matured tea leaves late in the first crop season or under the third leaf during the second crop season. The amount of EGCG3″Me contained in the stem was low. A higher concentration of strictinin was found in younger new shoots in the first crop, and the content greatly decreased during the second crop season. Thus, to obtain the anti-allergic benefits of EGCG3″Me, green tea should be made from fully-matured 'Benifuki' leaves under the fourth shoot late in the first crop or under the third shoot in the second crop, refined by removing stems. This green tea is lower in caffeine as compared with that made from younger shoots. On the contrary, to utilize strictinin, green tea should be made using younger new shoots of 'Benifuki.'.