Kitamura S, Hori T, Kurita K, Takeo K, Hara C, Itoh W, Tabata K, Elgsaeter A, Stokke B T
Department of Agricultural Chemistry, Kyoto Prefectural University, Japan.
Carbohydr Res. 1994 Oct 3;263(1):111-21. doi: 10.1016/0008-6215(94)00156-1.
A water-soluble, (1-->6)-branched (1-->3)-beta-D-glucan (H-3-B) was isolated from a hot-water extract of the fruiting bodies of the fungus, Cryptoporus volvatus (Basidiomycetes). Enzymatic analysis using exo-(1-->3)-beta-D-glucanase and methylation analysis indicated that this polysaccharide has a main chain composed of beta-(1-->3)-linked D-glucopyranosyl residues, and single, beta-(1-->6)-linked D-glucopyranosyl residues attached as side chains to, on average, every fourth sugar residue of the main chain. This structure was confirmed by 13C NMR spectra of the glucan in Me2SO-d6. The weight-average molecular weight (Mw) of H-3-B was determined to be 44.0 x 10(4) by gel permeation chromatography equipped with a low-angle laser-light-scattering photometer. The electron microscopic observations showed that H-3-B and its sonicated sample (S-H-3-B, Mw = 13.7 x 10(4)) can be described as linear worm-like chains. The mass per unit length for native and sonicated H-3-B was determined to be 1750 and 1780 g mol-1 nm-1, respectively, from the contour lengths obtained by electron microscopy and the molecular weights. These values are in good agreement with that expected for the triple stranded structure. A sample denatured in 0.1 M NaOH and subsequently renatured by neutralization showed a mixture of linear and cyclic structures, and larger aggregates with less well-defined morphology. The H-3-B and S-H-3-B had antitumor activity against the Sarcoma 180 tumor.
从真菌茯苓（担子菌纲）子实体的热水提取物中分离出一种水溶性的、（1→6）分支的（1→3）-β-D-葡聚糖（H-3-B）。使用外切（1→3）-β-D-葡聚糖酶进行的酶分析和甲基化分析表明，这种多糖的主链由β-（1→3）连接的D-吡喃葡萄糖残基组成，并且平均每四个主链糖残基上有一个单β-（1→6）连接的D-吡喃葡萄糖残基作为侧链连接。在Me2SO-d6中葡聚糖的13C NMR光谱证实了这种结构。通过配备低角度激光散射光度计的凝胶渗透色谱法测定H-3-B的重均分子量（Mw）为44.0×10⁴。电子显微镜观察表明，H-3-B及其超声处理样品（S-H-3-B，Mw = 13.7×10⁴）可描述为线性蠕虫状链。根据电子显微镜获得的轮廓长度和分子量，天然和超声处理的H-3-B的单位长度质量分别确定为1750和1780 g mol⁻¹ nm⁻¹。这些值与三链结构预期的值非常一致。在0.1 M NaOH中变性并随后通过中和复性的样品显示出线性和环状结构的混合物，以及形态不太明确的较大聚集体。H-3-B和S-H-3-B对肉瘤180肿瘤具有抗肿瘤活性。
