海南石莼多糖的提取与分离及其结构性质的初步研究

Extraction,Primary Structure and Properties Investigation of Polysaccharides from Ulva lactuca L.

在碱性条件下,从海南石莼中提取了石莼粗多糖,并对其进行了醇沉纯化,同时,对其多糖总糖、蛋白质、糖醛酸、硫酸基的含量进行了测定,并分析了多糖的结构,结果表明：在碱性条件下更有利于ULP的溶解;当料液比过高时会导致后续处理中多糖的流失,从而降低多糖产率;在碱液条件下,过长处理时间会导致多糖降解;石莼粗多糖的提取温度以70~90℃为宜.正交实验表明：石莼粗多糖的最佳提取工艺为：Na OH溶液的质量分数为2%,料液比为1∶80,在90℃恒温水浴5 h后再在90℃超声1 h,其提取率达17.57%.此外,检测了石莼多糖的理化性质,测定了其分子质量和纯度,并对其进行了红外光谱分析、元素分析以及表面活性测试.

In NaOH solution, polysaccharides （ULP） were extracted from Ulva lactuca L. , and the alcohol pre- cipitation and purification were performed. The contents of polysaccharides, protein, uronic acid, and sulfate group were determined and the structure of polysaccharides were analyzed. The extraction conditions were opti- mized through single factor experiments and orthogonal experiments. The results indicated that it was under the conditions of 2% NaOH, 90 ℃ , material/water ratio 1：80, liquid extraction 5 h and subsequent ultrasound-as- sisted extraction lh that the highest yield of 17.57% was obtained. The physic-chemical characters of ULP were analyzed, the molecular weight and purity were determined. The infrared spectrum analysis, element analysis and surface activity test were also performed.