白木通多糖的研究

STUDIES ON POLYSACCHARIDE FROM AKEBIA TRIFOLIATE (I)

用碱液从白木通（Ａｋｅｂｉａｔｒｉｆｏｌｉａｔｅ）茎中提取所得的粗多糖ＡＴＢ经ＤＥＡＥＣｅｌｕｌｏｓｅ及ＳｅｐｈａｄｅｘＧ２００柱层析后得到一多糖纯品ＡＴＢＢ２，其分子量为２３×１０５。糖组分分析ＡＴＢＢ２中各糖残基的摩尔比为Ｒｈａ∶Ａｒａ∶Ｘｙｌ∶Ｇａｌ∶Ｇｌｃ∶ＧａｌＡ＝１２２∶１００∶１１０∶０８５∶０２４∶０８２。经甲基化，高碘酸氧化，Ｓｍｉｔｈ降解，部分酸水解，１Ｈ和１３ＣＮＭＲ谱的分析揭示ＡＴＢＢ２是一个结构复杂的杂多糖。

Crude polysaccharide ATB was extracted from the stems of Akebia trifoliate with 5% NaOH. It was then subjected to DEAE Cellulose column chromatography and purified by Sephadex G 200 chromatography. Finally, a pure polysaccharide ATBB 2 was obtained. The molecular weight of ATBB 2 was estimated to be 2 3×10 5. By total acid hydrolysis, the analytical results indicated that ATBB 2 is composed of Rha, Ara, Xyl, Gal, Glc and GalA in a molar ratio of 1 22∶1 00∶1 10∶0 85∶0 24∶0 82. Methylation analysis, periodate oxidation analysis, Smith degradation, partial acid hydrolysis, 1H and 13 CNMR showed that ATBB 2 is a highly branched molecule without a main chain.