高粱酒糟高纯度黄酮的制备及其抗氧化活性

Preparation and Antioxidant Activity of High Purity Flavonoids from Sorghum Distillers’Grains

以高粱酒糟为原料,采用微波协同乙醇-磷酸氢二钾双水相的方法提取高粱酒糟黄酮,并用多级双水相体系纯化,研究高粱酒糟黄酮的制备条件及其抗氧化活性。实验结果表明,乙醇浓度80%,磷酸氢二钾用量180 mg/mL,液料比47∶1(V/m),提取时间60 s,微波功率为低火进行微波协同双水相高粱酒糟黄酮提取实验,黄酮得率为2.16%;二级双水相纯化,黄酮纯度可达82.58%。抗氧化实验表明:纯化后黄酮DPPH自由基清除率明显高于纯化前,但低于同一质量浓度的VC,二级双水相纯化有利增强黄酮抗氧化活性。

Using sorghum distiller’s grains as raw material,flavonoids were extracted by the method of microwave assisted ethanol and dipotassium hydrophosphate aqueous two-phase system,and purified by multi-stage aqueous two-phase system.The preparation conditions and antioxidant activity of the flavonoids were studied.The results indicated that under the conditions of 80%ethanol,180 mg/mL dipotassium phosphate,47∶1(V/m)liquid to material ratio,60 s extraction time and low microwave power,flavonoids were extracted from sorghum distiller′s grains.The yield of flavonoids was 2.16%,and the purity of xanthone was 82.58%.The antioxidant experiments indicated that the DPPH free radical scavenging rate of flavonoids after purification was significantly higher than that before purification,but lower than that of VC with the same mass concentration.The two-stage aqueous two-phase purification was beneficial to enhance the antioxidant activity of flavonoids.