大孔树脂纯化大蓟总黄酮工艺优化及其纯化前后抗氧化活性比较

Purification of total flavonoids from Cirsium japonicum DC.with macroporous resin and comparison of antioxidant activity of crude and purified flavonoids

目的 研究大孔树脂纯化大蓟总黄酮的最佳工艺条件并比较提取物与纯化物的体外抗氧化活性。方法 通过静态吸附-解吸实验选择适宜型号的大孔树脂后,采取动态吸附-解吸实验探讨大蓟黄酮提取物的最佳纯化条件,同时测定不同产物对羟自由基(·OH)和1,1-二苯基-2-苦基肼(DPPH·)自由基的清除率。结果 AB-8大孔树脂动态吸附-解吸大蓟黄酮提取物的工艺条件为:上样液浓度为2mg·mL^(-1)、上样流速为1mL·min^(-1)、上样液体积为60mL、乙醇体积分数为75%、洗脱流速为1mL·min^(-1)和洗脱液体积为80mL。纯化后大蓟黄酮的含量由17.6%提高至61.2%。体外实验结果表明,当大蓟黄酮纯化物浓度为1.0mg·mL^(-1)时,对DPPH·和·OH的清除率分别为88.9%、95.1%,较提取物均有提高。结论 采用最佳工艺条件纯化大蓟黄酮粗提物简便可行,且能进一步增强大蓟总黄酮的抗氧化活性。

OBJECTIVE To optimize the optimum process parameters for separation and purification of total flavonoids from Cirsium japonicum DC.with macroporous resin and to compare the antioxidant activities between crude and purified flavonoids.METHODS The static adsorption and desorption test were used for selection of suited type of macroporous resin and the best separation and purification conditions were confirmed by dynamic adsorption and desorption test.The scavenging ability of DPPH· and ·OH of the total flavonoids between different samples were determined.RESULTS The AB-8 macroporous resin was used as the purification resin of total flavonoids from Cirsium japonicum DC.with loading solution was 2mg·mL^(-1),loading flow velocity was 1mL·min^(-1),the volume of loading solution was 60mL,the ethanol concentration was 75%,the washing liquid elution flow rate was 1mL·min^(-1) whose amount was 80mL.Under this condition,the content of the total flavonoids in sample increased from 17.6% to 61.2%.The antioxidant test in vitro showed that the scavenging rates of DPPH· and ·OH were 88.9% and 95.1% respectively,when the mass concentration of purified sample was 1.0mg·mL^(-1),in which were all higher than that of crude flavonoids.CONCLUSION This optimum condition of purification could meet the application demand that convenience and feasibility,and the antioxidant activity of total flavonoids from Cirsium japonicum DC.was furthermore enhanced after purification.