超声辅助提取四齿四棱草中总黄酮及其抗氧化活性

Ultrasonic-assisted Extraction and Antioxidant Effects of Total Flavonoids from Schnabelia tetradonta

本文采用正交实验优选超声辅助提取四齿四棱草中总黄酮的最佳工艺,测定其含量,并以Vc为对照,采用DPPH法、ABTS法和FRAP法对四齿四棱草总黄酮抗氧化活性进行综合评价。通过单因素实验和正交实验,研究乙醇浓度、超声时间、料液比、提取温度对四齿四棱草中总黄酮提取率的影响,优选出超声辅助提取四齿四棱草总黄酮的最佳工艺:乙醇浓度为70%,料液比为1∶30 g/m L,50℃超声提取两次,每次30 min,四齿四棱草总黄酮提取率为4.78%。四齿四棱草总黄酮对DPPH自由基(IC_(50)=42.91μg/m L,最大清除率为88.57%)、ABTS自由基(IC_(50)=44.61μg/m L,最大清除率为92.86%)的清除能力较好,对Fe^(3+)的还原能力(AEAC=5380μmol/g)亦较强,是一种天然的抗氧化剂。

The objectives of this study were to optimize the ultrasonic-assisted extraction process of total flavonoids from Schnabelia tetradonta with orthogonal design and to determinate its antioxidant activity. The antioxidant activity of S. tetradonta was evaluated by three methods： DPPH radical scavenging,ABTS radical scavenging and FRAP assay,with Vc as the control. The single factor test and orthogonal design were used to select the optimal extraction condition with ultrasonication by studying the effect of ethanol concentration,ultrasonic time,solid-liquid ratio and extraction temperature on the extraction yield of flavonoids. The experimental results revealed that： the optimal extraction conditions were： ethanol concentration of 70%,solid-liquid ratio of 1 ∶ 30 g / m L,and extracting 2 times at 50 ℃,30 min each time. Under these conditions,the extraction yield of total flavonoids reached up to 4. 78%. In addition,total flavonoids of S. tetradonta showed strong DPPH radical scavenging activity（ IC（50）= 42. 91 μg / m L,the maximum scavenging rate was88. 57%）,ABTS radical scavenging activity（ IC（50）= 44. 61 μg / m L,the maximum scavenging rate was 92. 86%） and ferric reducing antioxidant power（ AEAC = 5380 μmol / g）. It is an effective and natural antioxidant.