对苦荞茶多糖(tartary buckwheat tea polysaccharide,TBTP)进行分离纯化和活性分析,为苦荞的进一步推广和应用提供理论依据。采用水提醇沉法获得TBTP,利用苯酚-硫酸法测定粗多糖中的糖含量,通过体外抗氧化评价体系研究TBTP对DPPH自由基、羟基自由基(·OH)、超氧阴离子(O2-·)的清除活性以及TBTP的总还原能力,并利用DEAE-52纤维素和G-150葡聚糖凝胶柱对获得的粗多糖进行纯化、分组。结果表明:TBTP的多糖含量为58.75%;在质量浓度为8.0 mg/m L时,对DPPH·的清除率为94.16%,对·OH的清除率为82.25%;在质量浓度为4.0 mg/m L时,对O2-·的清除率为98.05%。同时经DEAE-52纤维素和G-150葡聚糖凝胶柱对TBTP进行分离纯化后,将TBTP分为3个成分均一的组分,分别为TBTP-1、TBTP-2、TBTP-3。苦荞茶作为食源性物质,其多糖有明显的抗氧化活性。DEAE-52纤维素和G-150葡聚糖凝胶柱对该多糖有很好的分离、纯化效果。

Buckwheat tea polysaccharide purification and analysis provided a theoretical basis for the further promotion and application of buckwheat. Water-extraction and alcohol-precipitation was used to obtain TBTP,and sugar content of the coarse polysaccharide was determined by phenol-sulfuric acid method. The scavenging activity of the DPPH free radical,hydroxyl free radical( · OH),and superoxide anion( O-2·) and the total reducing power of TBTP were tested through vitro antioxidant evaluation system. Purification and TBTP separation was performed by Cellulose DEAE-52 and Sephaadex Column G-150. The experiment suggested the content of TBTP polysaccharide was58. 75%. When the mass concentration was 8. 0 mg / m L,the DPPH free radical clearance rate was 94. 16%,the clearance rate of OH was 82. 25%; When the mass concentration was 4. 0 mg / m L,the O-2· clearance rate was98. 05%. After separation and purification,TBTP was divided into three single-component : TBTP-1,TBTP-2,TBTP-3. The conclusion is that TBTP in tartary buckwheat tea had obvious antioxidant activity. DEAE-52 cellulose and G-150 glucan gel had obviously effect on separation and purification of the polysaccharide.