Institute of Food Chemistry, Technische Universität Braunschweig, Schleinitzstrasse 20, 38106 Braunschweig, Germany.
J Agric Food Chem. 2010 Jul 14;58(13):7820-30. doi: 10.1021/jf101023e.
Fifty-seven samples have been analyzed with regard to the occurrence of dimeric procyanidins B1-B8 as well as the composition of polymeric procyanidins. Fifty-two samples were found to contain polymeric procyanidins. In most of the samples, (-)-epicatechin was the predominant unit present. In white willow bark (Salix alba), however, large amounts of (+)-catechin (81.0%) were determined by means of phloroglucinolysis. White willow bark has therefore been used for the semisynthetic formation of dimeric procyanidins B3 [(+)-C-4alpha --> 8-(+)-C)], B4 [(+)-C-4alpha --> 8-(-)-EC)], B6 [(+)-C-4alpha --> 6-(+)-C)], and B8 [(+)-C-4alpha --> 6-(-)-EC)]. The reaction mixtures of the semisynthesis were successfully fractionated with high-speed countercurrent chromatography (HSCCC), and dimeric procyanidins B3, B4, B6, and B8 were obtained on a preparative scale.
对 57 个样品进行了分析，以研究二聚原花青素 B1-B8 的存在情况以及聚合原花青素的组成。发现 52 个样品含有聚合原花青素。在大多数样品中，（-）-表儿茶素是主要存在的单元。然而，在白柳树皮（Salix alba）中，通过间苯三酚法测定出大量的（+）-儿茶素（81.0％）。因此，白柳树皮被用于二聚原花青素 B3[（+）-C-4alpha --> 8-（+）-C）]，B4[（+）-C-4alpha --> 8-（-）-EC）]，B6[（+）-C-4alpha --> 6-（+）-C）]和 B8[（+）-C-4alpha --> 6-（-）-EC）]的半合成形成。半合成的反应混合物通过高速逆流色谱（HSCCC）成功地进行了分离，并在制备规模上获得了二聚原花青素 B3、B4、B6 和 B8。
