何晓兰 雷霆雯 许庆忠

摘要 [目的]研究不同方法提取苦荞蛋白的体外抗氧化活性。[方法]以贵州威宁种植的苦荞为材料，通过蛋白质含量测定、清除羟基自由基能力测定对碱溶酸沉法提取苦荞粗蛋白和Osborne法分级提取苦荞清蛋白、球蛋白、醇溶蛋白、谷蛋白进行了比较分析。[结果]通过碱溶酸沉法提取能获得大量的可溶性蛋白，Osborne法提取的蛋白虽然含量较低但获得的种类较多；各种蛋白均具有清除羥基自由基的能力，其清除羟基自由基能力从大到小依次为清蛋白、碱溶酸沉法提取的粗蛋白、谷蛋白、球蛋白、醇溶蛋白。[结论]碱溶酸沉法和Osborne法提取的苦荞蛋白均具有体外抗氧化能力。

关键词 苦荞蛋白；碱溶酸沉法；Osborne法；抗氧化活性

中图分类号 TS201.2+1 文献标识码 A 文章编号 0517-6611（2017）25-0134-02

Abstract [Objective] The research aimed to study the antioxidant activity in vitro of tartary buckwheat proteins by different methods. [Method]Tartary buckwheat proteins was prepared by alkalisolution and acidisolation， and albumin， globulin， prolamin and glutelin from tartary buckwheat were obtained by different solubility extraction. The coomassie brilliant blue protein quantitative was used in determination of protein concent and chemical colorimetric method was used to determinate the ability to remove hydroxyl radicals（·OH） of each protein fraction.[Result]The results showed that proteins obtained by alkalisolution and acidisolation methos were the predominant fraction. Proteins extracted by different methods had the ability to remove hydroxyl radicals， and the order of radical scavenging activity was albumin， proteins obtained by alkalisolution and acidisolation methods， glutelin， globulin and prolamin.[Conclusion]Both the alkalisoluble acid precipitation method and the Osborne method have the antioxidant capacity of tartary buckwheat protein.

Key words Tartary buckwheat proteins；Alkalisolution and acidisolation method；Osborne method；Antioxidant activity

苦荞，又名鞑靼荞麦，属于蓼科荞麦属。我国苦荞种植面积和产量均居世界第一位[1]，主要生长在我国的西南山区。《神龙书》中将苦荞认为是“五谷杂粮之王也”，说明苦荞是一种举足轻重的功能性食品，其营养价值和药用价值均较高。

已有文献报道，苦荞蛋白具有降低血浆胆固醇、改善便秘、抑制脂肪蓄积和预防肿瘤的作用[2]，这可能与苦荞蛋白的低消化率有关[3]。苦荞蛋白质的氨基酸组成比较均衡，具有较高的生物价值[4]。苦荞蛋白富含人体限制性氨基酸（赖氨酸、苏氨酸和蛋氨酸），精氨酸的含量也较高，与小麦相比，苦荞蛋白中谷氨酸和脯氨酸的含量低[5]。有研究报道苦荞蛋白的低消化率、赖氨酸和精氨酸的比例以及蛋氨酸和甘氨酸的比例是苦荞蛋白具有降低血浆胆固醇作用的关键因素[6]。……