绿茄叶黄酮的响应面优化提取及其对酪氨酸酶的抑制作用

Optimization of the extraction of flavonoids from green eggplant leaves by response surface and study on its inhibitory effect on tyrosinase

根据Box-Benhnken中心组合试验设计原理,在单因素试验的基础上采用三因素三水平的响应面分析法优化了绿茄叶黄酮的超声辅助硫酸铵的双水相提取工艺,并考察提取物对酪氨酸酶的抑制作用。结果表明,超声辅助乙醇-硫酸铵双水相体系提取绿茄叶黄酮的最优条件为:乙醇质量分数33%、硫酸铵质量分数20%、超声时间40 min、料液比1∶48(g/m L)。在最优工艺下,最大响应值(6.59%)和实验测定值(6.49%)基本符合,说明响应面法优化绿茄叶黄酮提取切实可行。同时,研究表明绿茄叶黄酮对蘑菇酪氨酸酶具有显著的抑制作用,抑制率随着绿茄叶黄酮质量分数的增大而增大,当质量分数为0.086 mg/m L时,绿茄叶黄酮对蘑菇酪氨酸酶的抑制率为45.7%。结果显示,绿茄叶含有大量的黄酮,并可有效抑制蘑菇酪氨酸酶的活性,具有潜在的开发利用价值。

In this work, in the ultrasonic-assisted ethanol-ammonium sulphate aqueous two-phase system, the extraction process of flavonoids from green eggplant leaves were optimized via response surface method with three factors and three levels based on the principle of Box-Behnken design. And the inhibitory effect of flavonoids on tyrosinase activity was investigated. The results showed that the optimal extraction conditions were ethanol concentration of 33%, ammonium sulphate concentration of 20%,extraction time of 30 min and material-liquid ratio of 1 ∶48, respectively. Under the above conditions, it was found that the maximum extraction yield of 6.49% was very close to the response value of 6.59%, indicating that response surface method was feasible to the optimization of extraction technique of flavonoids from green eggplant leaves. Meanwhile, the results showed that the tyrosinase activity of mushroom can be suppressed by flavonoid, which inhibitory rate increased along with the concentration of flavonoid. When the mass concentration of flavonoid was 0.086 mg/m L, the inhibitory ratio reached up to 45.7%. The flavonoid extracted from green eggplant leaves was an excellent natural product with inhibitory effect on tyrosinase.