红心与白心火龙果总糖、还原糖含量及其抗氧化活性的对比分析

Comparative analysis of total sugar, reducing sugar content and antioxidant activity in red pitaya and white pitaya

以红心与白心火龙果为原料,采用热水浸提法提取果肉中的糖分。分析比较2种火龙果总糖、还原糖含量及其抗氧化活性。试验表明,温度对糖分提取具有显著影响。在80℃时,红心火龙果总糖(28.68%)及还原糖(8.85%)含量均显著高于白心火龙果总糖(18.46%)及还原糖(7.09%)含量。抗氧化活性测试结果显示,其抗氧化活性随多糖浓度的升高而增强,其中红心火龙果多糖的抗氧化活性强于白心火龙果。当多糖浓度为2.0 mg/mL时,红心火龙果多糖对·OH、DPPH、NO2-的清除率可达73.44%、48.39%、47.59%,总抗氧化力为0.79,总还原力为0.65。

With red pitaya and white pitaya as raw material, sugar were extracted by hot water. The total sugar, reducing sugar content and antioxidant activities of 2 kinds of pitaya were analyzed and compared. The results showed that the content of total sugar(28.68 %), reducing sugar(8.85 %) in red pitaya, extracted at 80 ℃, were significantly higher than those(18.46 %, 7.09 %) in white pitaya. Investigations of antioxidant activity revealed that polysaccharides in red pitaya have better antioxidant activities than that in white pitaya. The clearance on hydroxyl radical(·OH), 1,1-diphenyl-2-picrylhydrazyl radical(DPPH), nitrite ion(NO2-) were 73.44 %, 48.39 %, 47.59 % respectively, the total antioxidant power was 0.79 and the total reducing power was 0.65 when the concentration of polysaccharides from red pitaya reached 2.0 mg/mL, which was more strong with higher concentration.