糙米黄酮的提取及其抗氧化作用的研究

Extraction of Flavonoids from Brown Rice and Its Antioxidant Action

本实验采用乙醇浸提法提取糙米黄酮。首先考察溶剂浓度、料液比、提取温度、提取时间等因素对提取率的影响。在单因素试验的基础上,根据正交试验设计原理,采用极差分析法,对提取条件进行优化。确定糙米黄酮的最佳提取工艺条件为:提取温度60℃,提取时间6 h,料液比为1∶40,乙醇浓度为60%,在此条件下糙米黄酮的提取量为0.556 mg/g。最后,以邻二氮菲-亚铁化学法测定其抗氧化作用。和VC对比,考察糙米黄酮对羟自由基(·OH)的清除能力,结果表明糙米黄酮对羟自由基(·OH)具有较强的清除能力,且在同质量浓度下,糙米黄酮对羟自由基(·OH)的清除能力大于VC对羟自由基的清除能力。

In this thesis,the extraction technology of total flavonoids from brown rice with alcohol was studied.The effects of solvent concentration,ratio of solid to liquid,extraction temperature,and extraction time on the extraction rate were investigated.On the basis of the single factor experiment,the extraction conditions were optimized by the range analysis method according to the orthogonal design principle.The optimum extraction conditions were as follows:the extraction temperature was 60℃,the extraction time was 6 h,the ratio of material to liquid was 1∶40,and the ethanol concentration was 60%.Under this condition,the extraction rate of brown rice flavonoids was 0.556 mg/g.Finally,the antioxidant activity was determined by o-phenanthroline-ferrous chemistry method,the results showed that the flavonoids of brown rice had a strong ability to scavenge hydroxyl radicals(·OH),and at the same concentration,was greater than the ability of VC to scavenge hydroxyl radicals.