微波辅助提取茭白总黄酮及其抗氧化性研究

Microwave-assisted extraction and antioxidative activity of flavonoids from Zizania

中文关键词:  茭白  总黄酮  微波  提取  抗氧化性

英文关键词:Zizania  flavonoids  microwave  extraction  antioxidative activities

中文摘要:

      目的 优化微波辅助乙醇提取茭白总黄酮的工艺条件, 评价茭白总黄酮的体外抗氧化能力。方法 通过标准曲线法测定茭白中总黄酮含量, 正交实验设计考察料液比、微波处理时间、浸提时间、微波功率等因素对黄酮得率的影响。以维生素C (L-ascorbic acid) 作为阳性对照, 研究其抗氧化活性, 包括总还原力及清除DPPH自由基、羟基自由基及超氧阴离子自由基的能力。结果 茭白总黄酮的最佳提取条件为料液比1:90 (w:v)、微波处理时间50 s、浸提时间3 h、微波功率320 W, 其得率为3.78%。结论 茭白总黄酮在低浓度下有一定的抗氧化性, 且其抗氧化性具有量效关系, 但综合抗氧化能力在低浓度下不如VC。

英文摘要:

      Objective To investigate the microwave-assisted process of ethanol for the extraction of total flavonoids from Zizania, and the antioxidant activities of the resultant total flavonoids. Methods The total flavonoids in Zizania was measured with standard curve, the impact of solid to liquid ratio, microwave processing time, extraction time, and microwave power on the yield of flavonoids were examined by orthogonal experimental. The flavonoids were further studied by testing their total reducing power and their scavenging capacity on the DPPH free radical, hydroxyl free radical, and superoxide anion free radical compared with the L-ascorbic acid. Results The optimum extraction condition were at solid-liquid ratio of 1:90 (w/v), microwave treatment time of 50s, alcohol extraction time of 3 h, and microwave power of 320 W with the extraction rate of 3.78%. Conclusion The resultant total flavonoids exhibited some antioxidant activities at low concentrations and their antioxidant activities displayed a dose-response relationship with their concentrations, but lower than those of L-ascorbic acid.