藜麦皂苷的提取及其酪氨酸酶抑制活性

Separation of Saponins from Chenopodium quinoa and Its Tyrosinase Inhibitory Activities

摘要:

探究藜麦“陇藜1号”籽粒中皂苷的最佳提取条件并验证其酪氨酸酶抑制活性。设计三因素三水平正交实验，探索料液比，乙醇浓度及超声时间对藜麦皂苷提取得率的影响。构建L-多巴诱导的B16细胞模型，测定藜麦皂苷对细胞活性及酪氨酸酶活性的影响，最终通过免疫印迹法（Western blot）探索藜麦皂苷影响酪氨酸酶活性的作用通路。结果显示：藜麦皂苷最佳提取条件为料液比1:40，70%浓度的乙醇下超声60 min，得率为17.85 mg/g。当藜麦皂苷的浓度低于200 μg/mL时，其对B16细胞无显著抑制作用，但能显著抑制酪氨酸酶的活性和黑色素的形成，200 μg/mL藜麦皂苷处理B16细胞72 h，黑色素相对含量降至73.85%，酪氨酸酶活性降至53.31%。藜麦皂苷通过抑制小眼畸型相关转录因子（MITF）及酪氨酸酶（TYR）蛋白表达来抑制黑色素形成。藜麦皂苷可以作为一种具有美白活性的组分在化妆品或药品中应用。

Abstract:

In order to explore the optimal extraction conditions of saponins from quinoa (Longli No.1) grains and to verify their tyrosinase inhibitory activity, three factors and three levels orthogonal experiments were designed to explore the optimum extraction conditions of the ratio of material to solution, ethanol concentration and ultrasonic time. L-dopa induced B16 cell model was established and the effects of quinoa saponin on cell activity and tyrosinase activity were measured. Finally, Western blot was used to explore the pathway of quinoa saponins affecting the activity of tyrosinase. The results showed that the best extraction conditions for quinoa saponins were 1:40 ratio of material to liquid, 70% ethanol under ultrasound for 60 min, and the yield was 17.85±0.88 mg/g. When the concentration of quinoa saponin was lower than 200 μg/mL, it had no significant inhibitory effect on B16 cells, but could significantly inhibit tyrosinase activity and melanin formation. When B16 cells were treated with 200 μg/mL chenopodin for 72 h, the relative content of melanin decreased to 73.85%, and the activity of tyrosinase decreased to 53.31%. Quinoa saponins inhibited the formation of melanin by inhibiting the expression of microphtalmia-associated transcription factor (MITF) and tyrosinase (TYR) proteins. Quinoa saponins can be used in cosmetics or medicines as a component with whitening activity.