超声辅助法制备的苜蓿多糖结构特征及抗氧化活性分析  

Structure characteristics and antioxidant activity of alfalfa polysaccharides prepared by ultrasonic assisted method

作　　者：李凤伟[1] 穆娜 柳晓晨 王笃军 商曰玲 余晓红[1] LI Fengwei;MU Na;LIU Xiaochen;WANG Dujun;SHANG Yueling;YU Xiaohong(Yancheng Institute of Technology,Yancheng 224051)

机构地区：[1]盐城工学院,盐城224051

出　　处：《中国食品添加剂》2022年第3期157-164,共8页China Food Additives

基　　金：国家自然科学基金项目(31802131);江苏省高等学校自然科学研究重大项目(19KJA480001)。

摘　　要：以紫花苜蓿为原料,采用超声辅助法提取苜蓿粗多糖,利用DEAE-52纤维素柱层析和Sephadex G-75凝胶柱层析分离纯化得到一种苜蓿均一多糖APSU-2a。通过高效凝胶渗透色谱、PMP柱前衍生化高效液相色谱、红外光谱和核磁共振波谱分析APSU-2a的结构特征,以DPPH、ABTS和羟自由基清除率评价APSU-2a的体外抗氧化活性。结果表明,APSU-2a的分子量为311.7kDa,主要由甘露糖、鼠李糖、半乳糖、阿拉伯糖四种单糖组成,还有少量葡萄糖醛酸和半乳糖醛酸。红外光谱和核磁共振结果显示APSU-2具有多糖类物质的典型特征吸收峰,并且同时存在α-型和β-型糖苷键。APSU-2a具有良好的抗氧化活性,在一定浓度范围内,APSU-2a的体外抗氧化活性具有浓度效应关系,可作为具有抗氧化作用的功能配料用于功能性食品的开发。The ultrasonic assisted method was used to prepare alfalfa crude polysaccharides.A homogeneous polysaccharides APSU-2 a was purified by DEAE-52 cellulose and Sephadex G-75 gel column chromatography.Structure characterization of APSU-2 a was analyzed by high performance gel permeation chromatography,precolumn PMP derivatization and high performance liquid chromatography,Fourier transform infrared spectrum(FTIR)and nuclear magnetic resonance spectroscopy(NMR).Its in vitro antioxidant activity was evaluated by scavenging ability of DPPH,ABTS and OH radicals.The results showed that the molecular weight of APSU-2 a was 311.7 kDa and was mainly composed of four monosaccharides:mannose,rhamnose,galactose and arabinose,with a small amount of glucuronic acid and galacturonic acid.FTIR and NMR spectroscopy analysis showed that APSU-2 a exhibited typical absorption peaks of polysaccharides,it also containedα-type andβ-type glycosidic bonds.APSU-2 a had a good antioxidant activity,within a certain concentration range,its in vitro antioxidant activity is concentration dependent.APSU-2 a can be used as a functional ingredient with antioxidant ability in the development of functional foods.

关 键 词：超声辅助 苜蓿多糖 分离纯化 结构特征 抗氧化活性 

分 类 号：TS202.1[轻工技术与工程—食品科学]