荞麦提取物抗氧化活性研究

以不同生育时期的甜荞和苦荞乙醇提取物为研究对象,在测定其提取物中总酚和总黄酮含量的基础上,利用体外法研究了荞麦提取物的总抗氧化性及对羟基自由基的清除作用。结果表明,参试品种总酚和总黄酮含量在整个生育期变化趋势一致,呈先升高后降低的变化趋势,在盛花期达到最高,苦荞含量高于甜荞,达0.05显著水平;两品种的乙醇提取物均有显著的抗氧化性,与甜荞相比,苦荞的总抗氧化活性以盛花期最强,羟基自由基的清除作用也最强,清除率达57.1%;回归分析表明,荞麦的总酚含量与总抗氧化性及对羟基自由基的清除率呈线性相关,相关系数可达0.90以上。

Antioxidant Activity of Ethanol Extracts of Different Buckwheat

The total phenolics and flavonoids and antioxidant capacities along with hydroxyl radical scavenging ability of common buckwheat and tartary buckwheat ethanol extracts in different development stage were examined.The results showed that the total phenolic and the flavonoids contents of common and tartary buckwheat unfolded a similar tendency in their whole growth time,both of which rose then declined and both achieved highest figures in the full-blossoming stage.The contents of the total phenolic and flavonoids of tartary buckwheat was higher than that of common buckwheat and all extracts exhibited good antioxidant activity.In the case of tartary buckwheat,its total antioxidant capacity and hydroxyl radical scavenging ability achieved(57.1%) highest in the full-blossoming stage.Significant and positive linear correlations were found between antioxidant capacities and phenolic contents(R2> 0.90),indicated that phenolics were the dominant antioxidant constituents in the buckwheat.