埔姜桑寄生的類黃酮素   全文下載

Flavonoids from Taxillus theifer

本實驗由埔姜桑寄生莖葉部得到一全新兒茶素衍生物－－catechin-5-O-(6-O-galloyl-β-glucopyranoside) (2)及 10個已知黃酮類化合物。埔姜桑寄生係一寄生性灌木，常寄生於不同種植物枝幹上。本研究收集3種來自不同宿主之埔姜桑寄生樣本，並利用高壓層析法對其化學成分之變化進行評估。3種不同宿主之埔姜桑寄生樣本中，其化學組成以catechin (1)，quercetin-3-O-(6-O-galloyl-β-glucopyranoside) (3)，quercetin-3-O-β-glucopyranoside (5) 和 quercetin-3-O-β-glucuronide (6)為主要成分，這些成分之存在無關於宿主種類。但各成分之相對含量變化卻因不同宿主而有所不同。

A new catechin derivative, catechin-5-O-(6-O-galloyl-β-glucopyranoside) (2), together with ten known flavonoids, was isolated from the leaves and stems of Taxillus theifer (Hayata) H. S. Kiu. T. theifer is a shrub parasitizing on different species of plants. Three samples of T. theifer on various host plants were collected and their chemical constituent variations were identified and esti-mated by HPLC/UV methods. A comparison of the constituents from T. theifer parasitizing on different host trees demonstrated that catechin (1), quercetin-3-O-(6-O-galloyl-β-glucopyranoside) (3), quercetin-3-O-β-glucopyranoside (5), and quercetin-3-O-β-glucuronide (6) were the major components in the title plant irrespective of the host tree. However, the content of some components varies for each sample.