龙须菜中硫琼脂的分离纯化及其成分分析

Isolation, Purification and Compositional Analysis of Agaropectin from Gracilaria lemaneiformis

采用EDTA-Na2浸提法提取硫琼脂,经DEAE Cellulose-52层析柱分段梯度洗脱得到3个多糖组分(SPS-1、SPS-2及SPS-3),并结合离子色谱法、高效液相色谱法、紫外光谱分析、红外光谱等多种分析手段,对其硫酸基含量、相对分子质量、纯度、单糖组成、特征键进行测定。结果表明:SPS-1、SPS-2、SPS-3的得率分别为2.7%、47.2%、2.2%,硫酸根含量分别为5.1%、9.3%、6.3%;硫琼脂结构中不含蛋白质、氨基酸和核酸;SPS-2中含有一种相似链长的多糖,其含量高达92.14%,重均相对分子质量(M w)为367686,数均相对分子质量(M n)为230434。可初判断,其是由17.34%半乳糖、2.72%棉子糖、8.82%蔗糖和1.18%阿拉伯糖等组成的结构复杂的硫酸酯多糖。

Three polysaccharides named as SPS-1, SPS-2 and SPS-3 were separated by gradient elution on a DEAE- cellulose column from the agaropectin extracted from Gracilaria lemaneiformis. Their chemical analysis including sulfate base content, relative molecular mass, purity, characteristic bonds and monosaccharide composition were characterized byion chromatography, high performance liquid chromatography, ultraviolet spectroscopy and infrared spectroscopy. The results indicated that the yields ofSPS-1, SPS-2 and SPS-3 were 2.7%, 47.2% and 2.2%, with sulfate base contents of 5.1%, 9.3% and 6.3%, respectively. The agaropectin contained no protein, amino acid or nucleic acid. The content of SPS-2 consisting of polysaccharides of similar chain length of was 92.14%. The mass-average and number-average relative molecular masses of SPS-2 were 367686 and 230434, respectively. SPS-2 was a group of complex sulfated polysaccharide with 17.34% galactose, 2.72% raffinose, 8.82% saccharose and 1.18% arabinose in the monosaccharide composition.