一种刺松藻来源的硫酸阿拉伯聚糖的制备及特征结构表征

刺松藻(Codium fragile)经水提-醇沉获得粗多糖, 进一步将刺松藻粗多糖(CFP) 通过Q-Sepharose Fast Flow(QFF) 阴离子交换柱纯化得到6个多糖组分CFP1CFP6, 其中, 在CFP6中发现纯度较高的阿拉伯聚糖. 采用高效凝胶渗透色谱与十八角激光散射仪联用法和1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生高效液相色谱法对CFP6的分子量及单糖组成进行了分析. 结果表明, CFP6是一种分子量为79290的多糖, 由阿拉伯糖(Ara)和半乳糖(Gal)组成, 二者摩尔比为14.8:1.0. 通过多维核磁共振波谱、 液相色谱-质谱联用及二级质谱等方法对CFP6的糖苷键连接方式及其寡糖序列结构进行表征, 进一步阐明了该复杂多糖的特征结构. 经判断, CFP6主链由Ara组成, 通过 β-(1→3)糖苷键连接, 在Ara的C2位存在分支结构, 硫酸基位于Ara的C4或C2位.

Sulfated Arabinose from Codium fragile: Preparation and Extensive Structural Characterization†

The crude polysaccharide was obtained from Codium fragile by water extracted and alcohol precipitated, and further 6 fractions purified by Q-Sepharose fast flow column were named CFP1—CFP6, respectively. CFP6 is a higher purity arabinose of them. The absolute molecular mass of the main fraction CFP6 was determined by high performance gel permeation chromatography and laser scattering instrument. The monosaccharide composition was analyzed by reversed phase high-performance liquid chromatography(RP-HPLC) labeled with 1-phenyl-3-methyl-5-pyrazolone(PMP). The results showed that CFP6 is a homogeneous polysaccharide component with a molecular weight of 79290 and consists of arabinose(Ara) and galactose(Gal) with a molar ratio of 14.8:1.0. Subsequently, the structural features and oligosaccharide sequence composition were identified by multi-dimensional nuclear magnetic resonance spectroscopy and liquid chromatography-mass spectrometry, further to elucidate the fine structure of the complex polysaccharide. The results revealed that the backbone of CFP6 is β-(1→3)-linked arabinan and sulfate group is located at the C4 or C2 positions. CFP6 is a higher purity arabinose and its extensive structure information can enrich the marine carbohydrate data and provides a methodological reference for the study of complex polysaccharide structures.