山楂核总黄酮的超声提取及抗氧化活性

Ultrasonic-assisted Ethanol Extraction of Flavonoids from Hawthorn Seed and Their Antioxidant Activity

采用超声辅助乙醇提取山楂核总黄酮,通过单因素实验方法和正交实验方法确定了总黄酮的最优提取工艺条件;与抗坏血酸、芦丁对比,利用羟基自由基(·OH)、1,1-二苯基-2-三硝基苯肼自由基(DPPH·)、Fe3+法测定山楂核总黄酮的抗氧化活性。结果表明,山楂核总黄酮超声辅助提取的最佳提取工艺为:按料液比为1∶25(每克山楂核加入25 m L提取剂,下同),加入体积分数50%的乙醇,在60℃下用250 W超声辅助提取40 min,山楂核中总黄酮的提取率可达到7.89%。经过纯化的山楂核总黄酮提取物对·OH和DPPH·具有明显的清除力且对Fe3+有较强的还原能力;黄酮纯化物的抗氧化作用随质量浓度增大而增强,其抗氧化能力强于芦丁而弱于抗坏血酸。

Flavonoids were extracted from Hawthorn seed under ultrasonic assistance,with ethanol as extraction solvent. The technical conditions were investigated based on single factor and orthogonal tests. Meanwhile,compared with ascorbic acid and rutin,the antioxidant activity of flavonoids was evaluated by scavenging DPPH radical,hydroxyl radical and method of Fe3 ＋. The results showed that the optimal ultrasonic-assisted extraction condition of flavonoids from Hawthorn seed were shown as follows： ethanol volume fraction of 50%,material-to-liquid ratio of 1 ∶ 25（ 25 m L liquid per gram materials）,ultrasonic power of 250 W,ultrasonic-assisted extracting time of about 40 min and extraction temperature at 60 ℃. The extraction rate of flavonoids reached 7. 89%. The flavonoid extraction exhibited obviously ability of scavenging DPPH free radical and OH free radical,and showed a higher reducing capacity to Fe3 ＋. The antioxidant activity increased with the increase of the concentration of purified flavonoids,which was superior to rutin but inferior to ascorbic acid.