Kiyohara H, Hirano M, Wen X G, Matsumoto T, Sun X B, Yamada H
Oriental Medicine Research Center of the Kitasato Institute, Tokyo, Japan.
Carbohydr Res. 1994 Oct 3;263(1):89-101. doi: 10.1016/0008-6215(94)00151-0.
Structural characterisation of an anti-ulcer polysaccharide (GL-BIII), purified from leaves of Panax ginseng C.A. Meyer, was studied. Methylation analysis indicated that GL-BIII consisted mainly of terminal Arap, 4- or 5-substituted Ara, 2,4-disubstituted Rha, 4- and 6-substituted Gal, and 3,6-disubstituted Gal. Single radial gel diffusion using beta-glucosyl-Yariv antigen indicated that GL-BIII contained a small proportion of a beta-(1-->3,6)-galactan moiety. GL-BIII also contained terminal, 4-substituted, and 3,4-disubstituted GalA, and terminal and 4-substituted GlcA. Base-catalysed beta-elimination suggested that some 2-substituted Rha in GL-BIII was attached to position 4 of a 4-substituted uronic acid. Both mild acid hydrolysis and endo-alpha-(1-->4)-polygalacturonase digestion of GL-BIII did not give fragments consisting mainly of GalA. Methylation analysis and GC-MS analysis of acidic oligosaccharides liberated by partial acid hydrolysis indicated that GL-BIII contained a GalA-(1-->4)-Rha unit in addition to longer acidic units consisting of 2-substituted Rha and 4-substituted GalA. Lithium-mediated degradation of GL-BIII followed by borohydride reduction gave small amounts of fractions containing long and intermediate neutral oligosaccharide-alditols and a large amount of a fraction containing short oligosaccharide-alditols. The long neutral oligosaccharide-alditol fraction mainly comprised 4- or 5-substituted Ara, terminal Galf, 6-substituted Glc, and 2-substituted Man, whereas the intermediate oligosaccharide-alditol fraction consisted mainly of terminal and 6-substituted Galp, 6-substituted Glc, and 2-substituted Man. Methylation analysis and GC-MS analysis of the short oligosaccharide-alditol fraction suggested that it contained at least 14 kinds of di- to tetra-saccharide-alditols such as Gal-(1-->2)-Rha-ol, Gal-(1-->4)-Rha-ol, Ara-->Ara-ol, and Ara-->Ara-->Ara-ol.
对从人参（Panax ginseng C.A. Meyer）叶中纯化得到的一种抗溃疡多糖（GL-BIII）进行了结构表征研究。甲基化分析表明，GL-BIII主要由末端阿拉伯糖（Arap）、4-或5-取代的阿拉伯糖（Ara）、2,4-二取代的鼠李糖（Rha）、4-和6-取代的半乳糖（Gal）以及3,6-二取代的半乳糖组成。使用β-葡萄糖基-亚里夫抗原进行的单向辐射凝胶扩散表明，GL-BIII含有少量的β-(1→3,6)-半乳聚糖部分。GL-BIII还含有末端、4-取代以及3,4-二取代的半乳糖醛酸（GalA），以及末端和4-取代的葡萄糖醛酸（GlcA）。碱催化的β-消除反应表明，GL-BIII中一些2-取代的鼠李糖连接在4-取代的糖醛酸的4位上。GL-BIII的温和酸水解和内切α-(1→4)-聚半乳糖醛酸酶消化均未产生主要由半乳糖醛酸组成的片段。对部分酸水解释放的酸性寡糖进行甲基化分析和气相色谱-质谱分析表明，GL-BIII除了含有由2-取代的鼠李糖和4-取代的半乳糖醛酸组成的较长酸性单元外，还含有一个半乳糖醛酸-(1→4)-鼠李糖单元。GL-BIII经锂介导降解后再用硼氢化钠还原，得到少量含有长和中等长度中性寡糖醇的馏分以及大量含有短寡糖醇的馏分。长中性寡糖醇馏分主要由4-或5-取代的阿拉伯糖、末端半乳糖（Galf）、6-取代的葡萄糖（Glc）和2-取代的甘露糖（Man）组成，而中等长度寡糖醇馏分主要由末端和6-取代的半乳糖（Galp）、6-取代的葡萄糖和2-取代的甘露糖组成。对短寡糖醇馏分进行甲基化分析和气相色谱-质谱分析表明，它至少含有14种二糖至四糖醇，如半乳糖-(1→2)-鼠李糖醇、半乳糖-(1→4)-鼠李糖醇、阿拉伯糖→阿拉伯糖醇和阿拉伯糖→阿拉伯糖→阿拉伯糖醇。
