香蓼总黄酮提取液提取条件及其体外抗氧化活性考察评价

Study on extraction conditions and antioxidant activity in vitro of total flavonoids extract from polygonum viscosum

探讨香蓼总黄酮提取液的最佳提取工艺条件及其体外抗氧化活性。在单因素试验的基础上,采用正交试验,确定香蓼总黄酮提取液提取的最佳工艺条件,并通过1,1-二苯-2-苦基肼自由基(DPPH·)清除率和还原能力的测定对香蓼总黄酮提取液进行体外抗氧化活性评价。结果表明,香蓼总黄酮提取液提取的最佳工艺条件为提取温度60℃,乙醇浓度70%,料液比1∶20,提取时间15 min,提取2次。采用该工艺条件测得香蓼总黄酮的含量为145.0±0.2 mg/g,平均回收率为99.78%,变异系数为1.00%(n=5)。体外抗氧化活性结果表明,香蓼总黄酮提取液的还原能力和DPPH·清除率与特丁基对苯二酚(TBHQ)接近,且香蓼总黄酮DPPH·半数抑制浓度(EC50=0.022 mg/m L)也与TBHQ(EC_(50)=0.015 mg/m L)相似,但远小于其他中草药。分析认为,香蓼总黄酮具有较强的抗氧化活性,是一种天然的抗氧化活性剂。

To optimize the extraction process of total flavonoids extract in polygonum viscosum and its in vitro antioxidant activity. The optimum technological parameters of extraction for total flavonoids extract from polygonum viscosum were determined by the orthogonal experiment on the basis of single factor experiment. The antioxidant activity was evaluated though detecting DPPH, scavenging rate and reducing activity test. The results showed that optimal technological factors for total flavonoids extract from polygonum viscosum were as follows ： extraction temperature was 60℃, ethanol concentration was 70% （v/v）, solid to liquid was 1 ： 20, extraction time was 15 rain, and extraction times were 2 times. Under the optimal conditions, it was found that the total flavonoids content in the polygonum viscosum was 145.0±0.2 mg/g, average recovery rate of total flavonoids in the polygonum viscosum was 99.78%, variation coefficient was 1.00% （n=5）. The results of in vitro antioxidant test indicated that the antioxidant activity of total flavonoids extract in the polygonum viscosum was the same as tertiary butylhydroquinone （TBHQ）, and the EC50 value （0.022 mg/mL） of DPPH·scavenging rate from polygonum viscosum was the same as the EC50 value （0.015 mg/mL）of TBHQ, but was much less than other Chinese medicinal herbs. Analysis results show that the total flavonoids ofpolygonum viscosum have stronger antioxidant activity and is a natural antioxidant agent.