苔麸总黄酮提取工艺及体外抗氧化活性研究

Study on Extraction Technology and Antioxidant Activity of Total Flavonoids from Eragrostis tef in Vitro

以苔麸为原料,进行苔麸总黄酮提取工艺及其体外抗氧化活性的研究。以芦丁为标准品,采用NaNO2-Al(OH)3-NaOH法测定苔麸总黄酮提取量,在单因素基础上,利用响应面法考察乙醇体积分数、料液比、提取时间、提取温度对苔麸总黄酮提取量的影响。结果显示:最优提取工艺为乙醇体积分数60%、料液比1∶20(g/mL)、提取时间71min、提取温度80℃,在最优条件下总黄酮提取量为144.0mg/100g。苔麸总黄酮提取液对2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐自由基(ABTS^+·)和羟基自由基(·OH)清除率最高分别达到99.23%和57.78%,表明其具有一定的抗氧化能力。

The extraction technology of total flavonoids from Eragrostis tef and its antioxidant activity in vitro were studied. The total flavonoids extracted from Eragrostis tef were determined by NaNO2-Al(OH)3-NaOH method with rutin as standard. On the basis of single factor,the effects of ethanol volume fraction,material-liquid ratio,extraction time and extraction temperature on the total flavonoids extracted from Eragrostis tef were investigated by response surface methodology.The results showed that the optimum extraction conditions were ethanol volume fraction 60 %,solid-liquid ratio 1 ∶ 20 (g/mL),extraction time 71 min,extraction tempe-rature 80 ℃. Under the optimum conditions,the total flavonoids were extracted by 144.0 mg/100 g. The highest scavenging rates of 2,2-diazo-bis (3-ethyl-benzothiazole-6-sulfonic acid) diammonium salt free radical (ABTS^+·) and hydroxyl radical (· OH) were 99.23 % and 57.78 %,respectively,indicating that the extract of total flavonoids from Eragrostis tef had certain antioxidant activity.