荷叶黄酮的复合法提取及清除自由基的研究

Study on Flavonoids Composite Extraction from Lotus Leaf and its Radicals Scavenging Capacity

超声波与微波复合法提取荷叶中黄酮类化合物,最佳提取条件为乙醇浓度60%、料液比1∶25、超声提取时间25 min、微波功率462 W、微波提取时间90 s,荷叶黄酮提取率为2.45%。荷叶黄酮清除羟自由基和超氧阴离子自由基能力的研究表明,在荷叶黄酮分别为125 mg/L和3.5 mg/L(以芦丁计)时,可以清除50%的羟自由基和超氧阴离子自由基。实验表明,荷叶黄酮对羟自由基和超氧阴离子自由基具有良好的清除效果,进而为荷叶作为天然抗氧化剂提供了参考。

Lotus leaf flavonoids were extracted by ultrasonic and microwave.The optimal process conditions for flavonoids extraction was obtained to extract 25 minutes with 60 % alcohol when solid-to-liquid ratio was 1∶25 by ultrasonic.And then extracts were extracted 90 seconds when power was 462-watt by microwave.Extraction yield of flavones was 2.45 %.Flavonoids activities to scavenge hydroxy radicals and superoxide radicals were examined.When flavonoids（rutin as reference substance） were 125 mg/L and 3.5 mg/L,50 % hydroxy radicals and superoxide radicals were scavenged.The results showed that lotus leaf flavonoids has hydroxy radicals and superoxide radicals scavenging capacity.It provides a theoretical basis for Lotus leaf as natural antioxidant.