乙醇-硫酸铵双水相萃取黄秋葵叶中的叶黄素

Extraction of Lutein from Okra Leaves by Ethanol-Ammonium Sulfate Aqueous Two-Phase System

以天然黄秋葵叶经冻干粉碎后的粉末为原料,构建萃取叶黄素的乙醇-硫酸铵双水相体系。在单因素实验的基础上对乙醇质量分数、硫酸铵质量分数和粗提液质量分数进行三因素三水平的响应面优化,结果表明优化萃取工艺条件为粗提液质量分数6%、乙醇质量分数14.5%、硫酸铵质量分数27.5%、得率为1.99 mg/g,且超声辅助萃取叶黄素的动力学研究表明超声辅助萃取叶黄素过程符合二级动力学方程。此方法萃取的叶黄素以V C做对照,对ABTS自由基和DPPH自由基的IC 50值分别为0.2841和0.7633 mg/mL,具有一定的抗氧化性。

In this study,an aqueous two-phase system composed of ethanol and ammonium sulfate was selected to extract lutein from freeze-dried okra leaf powder.On the basis of single factor test,the response surface of ethanol mass fraction,ammonium sulfate mass fraction and crude extract mass fraction were optimized with three factors and three levels.The results showed that the optimized extraction process conditions were 6% of crude extract,14.5% of ethanol and 27.5% of ammonium sulfate.The yield was 1.99 mg/g under this condition.The kinetic study of the crude extract of lutein from ultrasonic assisted extraction showed that the extraction conforms to the second order kinetic equation.The lutein extracted by this method was compared by V C,and the IC 50 value of lutein on ABTS free radical and DPPH free radical were 0.2841 and 0.7633 mg/mL,respectively,which had certain antioxidant activity.