摘要
为深入了解牛大力糖蛋白的结构组成、理化性质和生物活性,根据牛大力粗糖蛋白(MSCG)的分子质量分布情况,采用超滤、凝胶柱层析(Sephadex G-75)、反相C-18色谱柱层析(ODS)方法,对牛大力粗糖蛋白进行分离纯化,得到两种组分MSCG-1和MSCG-2.通过HPLC、GC、GC-MS、红外光谱等方法对两种组分的结构进行了鉴定.结果表明:MSCG-1的分子质量约为62.0 ku,MSCG-2的分子质量约为1.94 ku;MSCG-1含50.22%的蛋白质和38.07%的糖,糖链主要由→4,6)-Galp-(1→和Araf-(1→构成;MSCG-2含69.37%的蛋白质和6.70%的糖,糖链由→6)-Glcp-(1→构成主链,糖链分支度高;MSCG-1和MSCG-2中都含有O-糖肽键.MSCG-2中含有的可能对抗氧化有贡献的氨基酸总量比MSCG-1中的高31.3%;MSCG-1和MSCG-2的氧自由基吸收能力分别为(56.10±18.49)和(1077.19±60.82)μmol/g;MSCG-2的抗氧化活性明显高于MSCG和MSCG-1,说明糖蛋白的分子组成、分子质量大小及结构特性决定了其抗氧化活性.
In order to understand well the structural characteristics,physical and chemical properties and biological activities of glycoprotein from Millettia Speciosa Champ.( MSCG),MSCG was purified by means of ultrafiltration,chromatography Sephadex G-75 and ODS according to its molecular mass distribution,and thus two purified fractions MSCG-1 and MSCG-2 were obtained. Then,the structures of the two fractions were identified by means of HPLC,GC,GC-MS and FT-IR. The results show that( 1) the molecular masses of MSCG-1 and MSCG-2 are62. 00 ku and 1. 94 ku respectively;( 2) MSCG-1 contains 50. 22% protein and 38. 07% sugar,and it is mainly composed of →4,6)-Galp-( 1→ and Araf-( 1→;( 3) MSCG-2 contains 69. 37% protein and 6. 70% sugar,and its main chain is composed of →6)-Glcp-( 1→ and has a high branch degree;( 4) MSCG-1 and MSCG-2 both contain O-link bonds;( 5) for the amino acid which may be of antioxidant activities,its content in MSCG-2 is 31. 3%higher than that in MSCG-1;( 6) the oxygen radical absorbance capacities( ORAC) of MSCG-1 and MSCG-2 are( 56. 10 ± 18. 49) and( 1 077. 19 ± 60. 82) μmol/g; and( 7) the antioxidant activity of MSCG-2 is significantly higher than those of MSCG and MSCG-1,which means that the molecular composition,molecular mass and structural characteristics of glycoprotein determine their antioxidant activities.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2015年第11期8-15,共8页
Journal of South China University of Technology(Natural Science Edition)
基金
广东省教育部产学研结合项目(2012B090600025)~~
关键词
牛大力
糖蛋白
分离
纯化
结构鉴定
抗氧化剂
Millettia Speciosa Champ.
glycoprotein
separation
purification
structure identification
antioxidants
