马齿苋中总黄酮提取工艺优化及其抗氧化活性研究

摘要

采用直接回流法提取马齿苋中总黄酮，通过单因素实验与正交实验对提取工艺进行了优化；并以芦丁为对照品，采用分光光度法对马齿苋中的总黄酮含量进行了检测；同时研究了马齿苋总黄酮提取液对羟基自由基（·OH）和超氧阴离子自由基（·O－2）的清除效果，并与 Vc 的抗氧化活性进行了比较。确定马齿苋中总黄酮最优提取工艺为：提取时间50 min、水浴温度90℃、提取溶剂为30％乙酸乙酯、固液比1∶50（g∶mL），在此条件下，马齿苋总黄酮提取率可达7.15 mg·g－1。当马齿苋总黄酮浓度为0.18 mg·mL－1时，对· OH 的清除率高达73.12％，对· O－2的清除率可达49.02％，相同浓度时，其抗氧化活性低于 Vc。%Total flavonoids were extracted from purslane by direct reflux.The extraction process was opti-mized by single factor experiment and orthogonal experiment.The content of total flavonoids from purslane was determined by spectrophotometric method using rutin as reference substance.Scavenging efficiency of total fla-vonoids from purslane to ·OH and ·O-2 were studied and compared with that of Vc.The optimal extraction process was obtained as follows:extraction time of 50 min,water bath temperature of 90 ℃,30% ethyl acetate as extraction solvent,and solid-liquid ratio of 1∶50(g∶mL).Under the optimal conditions,the extraction rate of total flavonoids from purslane could reach as high as 7.15 mg· g-1 .When the concentration of total fla-vonoids from purslane was 0.18 mg·mL-1 ,the scavenging rate of ·OH was 73.12% and the scavenging rate of ·O-2 was 49.02%.The antioxidant activity of Vc was better than those of total flavonoids from purslane at the same concentration.