知识与财富的链接
该研究首先采用单因素及Box-Behnken响应面试验优化红景天多酚提取工艺,然后构建体外α-葡萄糖苷酶抑制体系,研究红景天多酚α-葡萄糖苷酶抑制活性,同时通过酶抑制动力学,判断其抑制类型。单因素及响应面结果表明,最佳提取工艺条件为：乙醇浓度71%、料液比1:40、超声功率320 W、超声温度55℃,此条件下红景天多酚提取得率可达11.45%;红景天多酚对α-葡萄糖苷酶具有一定的抑制活性,且抑制能力呈量效关系,半数抑制浓度（IC50）为2.83 mg/mL,低于阳性对照阿卡波糖（IC50为3.36 mg/mL）,当红景天多酚浓度为50 mg/mL时,抑制率可达97.86%;酶抑制动力学研究表明,红景天多酚对α-葡萄糖苷酶为可逆混合型抑制类型,随着抑制剂浓度增大,其最大反应速率Vmax减小、米氏常数Km增大,属于竞争与非竞争性混合类型。此优化试验有效可行,且提取的红景天多酚在体外对α-葡萄糖苷酶具有较好抑制活性。
In this study, univariate and Box-Behnken response surface experiments were used to optimize the polyphenol extraction process of Rhodiola rosea. Then, a α-glucosidase inhibition system was constructed in vitro to study the inhibition activity of Rhodiola rosea polyphenols. At the same time, the type of inhibition was judged by enzyme inhibition kinetics. The univariate and response surface results showed that the optimal extraction process conditions were: Ethanol concentration of 71%, feed-to-liquid ratio 1:40, ultrasonic power 320 W, ultrasonic temperature 55 °C. Under this condition, the yield of Rhodiola rosea polyphenol extraction could reach 11.45%. Rhodiola rosea polyphenols had certain inhibitory activities on α-glucosidase, and the inhibition ability was quantitatively effective. Half inhibition concentration (IC50) was 2.83 mg/mL, lower than the positive control acarbose (3.36 mg/mL of IC50). When Rhodiola rosea polyphenol concentration was 50 mg/mL, the inhibition rate could reach 97.86%. Enzyme inhibitory kinetic studies showed that Rhodiola rosea polyphenols were reversible hybrid inhibitory types of α-glucosidase. As the concentration of the inhibitor increased, the maximum reaction rate Vmax decreased and the Michael's constant Km increased, which belonged to the competitive and non-competitive mixed types. This optimization test was effective and feasible, and the extracted Rhodiola rosea polyphenols had good inhibitory activity against α-glucosidase in vitro.
