铁皮石斛花色苷的超声波辅助提取工艺及抗氧化活性

Ultrasonic Assisted Extraction of Anthocyanin from Dendrobium Officinale and Its Antioxidant Activity

以铁皮石斛为原料,研究花色苷的超声波辅助提取工艺条件及其抗氧化活性,通过单因素结合正交试验对提取条件进行优化,结果表明最佳提取条件为:乙醇体积分数30%,料液比1:20,超声温度40℃,超声时间70 min,超声波功率180 W,提取到的花色苷含量为0.357 mg/g;在此条件下提取三次后花色苷含量达0.427 mg/g,体积分数为21.37 mg/L。对三次的提取液浓缩后进行抗氧化活性分析,结果表明:铁皮石斛花色苷具有较好的抗氧化活性,且花色苷的清除能力随体积分数的增大而增大,总花色苷提取液21.37 mg/L对羟自由基的清除率达90.2%,对DPPH自由基的清除率达94.1%;根据IC50值的比较可知花色苷的清除效果明显优于同体积分数梯度的抗坏血酸对照。

Using Dendrobium officinale as raw material, ultrasonic assisted extraction ofanthocyanin and its antioxidant activity were studied. The extraction conditions were optimized bysingle factor and orthogonal test. The results showed that the optimal extraction conditions were：the volume fraction of ethanol is 30：20, the ratio of material to liquid is 1：20, the ultrasonictemperature is 40 ℃, the ultrasonic time is 70 min, the ultrasonic power is 180 W, the extractedanthocyanin content is 0.357 mg/g. Under these conditions, the anthocyanin content reached 0.427mg/g, and the volume fraction was 21.37 mg/L after three times of extraction. The antioxidantactivity was analyzed after the concentration of three times of extract. The results showed that：Anthocyanin of Dendrobium officinale had better antioxidant activity, and the scavenging ability ofanthocyanin increased with the increase of volume fraction. The scavenging rate of hydroxyl radicalin total anthocyanin extract of 21.37 mg/l was 90.2%. The scavenging rate of DPPH free radicalwas 94.1%. According to the comparison of IC50 value, the scavenging effect of anthocyanin wasbetter than that of ascorbic acid with the same integral number gradient.