建宁莲子糖蛋白的分离、纯化及清除自由基作用

Isolation,Purification of Glycoproteins from Seed of Nelumbo nucifera Gaertn.Fujian and its Effect on Scavenging Free Radicals

从红花建莲 (N elumbo nucifera Gaertn.Fujian)的莲子中提取出具有生物活性的糖蛋白 (GL P) ,并进行清除自由基作用的研究。用 6 0 % (NH4 ) 2 SO4 饱和溶液沉淀蛋白质 ,经 Con A - Sepharose 4 B亲和层析柱分离 ,SephadexG- 15 0凝胶层析柱纯化 ,得到 2个组分的糖蛋白 ,分子量分别为 2 5 k D的 GL P- 和 92 .5 k D的 GL P- ,后者为其主要成分。 GL P中蛋白质含量是 5 8.8% ,总糖含量是 36 .4 %。 TL C和 GC分析结果 :GL P- 是由 L -鼠李糖 ,D-木糖 ,D-甘露糖和 D-葡萄糖组成。其中性糖摩尔比 :1.0 8:0 .92 :2 .5 4 :4 .15。 GL P- 是由 L -鼠李糖 D-木糖 ,D-甘露糖 ,L -阿拉伯糖 ,D-半乳糖 ,D-葡萄糖和 D-葡萄糖醛酸组成 ,其中性糖摩尔比 :1.2 5 :1.0 3:2 .85 :0 .94 :3.16 :4 .6 5。药理实验表明 :两种糖蛋白均有清除自由基的作用 ,而 GL P- 清除能力大于 GL P-

A bioactive glycoprotein(GLP) was isolated and purified from seed of Nelumbo nucifera Gaertn.Fujian and it plays a role in scavenging free radicals.The glycoprotein was precipitated in 60% saturanted solution of (NH 4) 2SO 4 first,was purified by ConA Sepharose 4B affinity chromatography and by Sephadex G 150 gel filtration chromatsgraphy consecutively, and last was aftained two parts of glycoproteins: GLP Ⅰ of molecular weight is 25 kD and GLP Ⅱ of molecular weight is 92 5 kD.A GLP Ⅱ is primary part in GLP.Contents of protein and total sugars of GLP are 58 8% and 36 4% respectively.By TLC and GC analysis resulted that, glycosyls of GLP Ⅰ are L rhamnose, D arabinose, D mannose and D glucose, and its molar ratios of neutral sugars are 1 08∶0 92∶2 54∶4 15 and glycosyls of GLP Ⅱ are L rhamnose, D arabinose,D manmose, L xylose,D galactose,D glucose and D glucuronic acid,and its molar ratio of neutral sugars are 1 25∶1 03∶2 85∶0 94∶3 16:4.65.Phamarcological tests showed that, GLP Ⅰ and GLP Ⅱboth could scavenigered free radical and scavenging effect of GLP Ⅱis higher than of GLP Ⅰ.