海带多糖的提取及组份LI的分离与鉴定

采用热水提取法考查了海带多糖的提取条件对多糖提取率的影响。实验结果表明，海带多糖的最佳提取温度为１００℃，提取时间为６ｈ，加水量为９０ｍＬ·ｇ－１。海带粗多糖经ＤＥＡＥ－纤维素（ＤＥ－５２，Ｂ４Ｏ２－７型）柱层析分离，以０．０５ｍｏｌ／Ｌ硼砂溶液为洗脱液，得到一种水溶性多糖（ＬＩ），通过纸层析、ＳｅｐｈａｄｅｘＧ－２００柱层析检查为单一组成，其酸性水解物经纸层析检查，表明其单糖组成为木糖、葡萄糖、岩藻糖，并含有硫酸基。葡聚糖凝胶过滤层析法测得其相对分子质量近似为１．１×１０５。ＬＩ结构鉴定有待于进一步研究。

Studies on Extration of Polysaccharides from Laminaria Japonica and Isolation Purification and Identification of Polysaccharde LI

The influences of three conditions on the yeild of polysaccharides for extracting polysaccharides from Laminaria Japonica have been investigated. The results of the experiment show that, compared with the other two conditions, temperature is the key condition, and the appropriate temperature should be 100℃, the relative amount of water should be 90mL·g-1, and extracting time should be six hours. A soluble polysaccharide (LI) which composed of xyloes, glucose and fucose was isolated by DEAE-cellulose (DE-52, in B4O2-7 form) chromatographic separation. By gel filtration on sephadex G-200, with 0.9% sodium chloride as the eluant, the molecular weight (W) of LI was estimated to be 1.1×105. 