药蜀葵中总黄酮提取工艺优化及其生物活性研究

Extraction optimization and biological activities of total flavonoids from Althaea officinalis

目的优选药蜀葵中总黄酮的最佳提取工艺,并探讨其体外抗氧化和抗α-葡萄糖苷酶活性。方法基于单因素实验,选择料液比、提取时间和乙醇浓度为自变量,应用Box-Benhnken中心组合法进行药蜀葵总黄酮响应面分析,并采用D101大孔树脂对获得的总黄酮进一步富集纯化。考察药蜀葵总黄酮抗氧化和抗α-葡萄糖苷酶活性。结果工艺优化结果表明,药蜀葵中总黄酮最佳提取条件为:提取次数2次,提取温度80℃,料液比为1∶25(g/mL),乙醇浓度49.0%,提取时间2.0 h,总黄酮的平均提取率为2.15%;经富集纯化所得总黄酮纯度为53.62%。体外活性研究结果表明,药蜀葵总黄酮有明显的清除DPPH和ABTS自由基的活性,其IC_(50)值分别为(8.36±0.06)μg·mL^(-1)和(8.45±0.14)μg·mL^(-1);同时具有显著的α-葡萄糖苷酶抑制活性,IC_(50)值为(76.63±1.12)μg·mL^(-1)。结论本研究首次对药蜀葵总黄酮的提取工艺进行优化,并发现其具有体外抗氧化及α-葡萄糖苷酶活性抑制作用,为药蜀葵总黄酮的开发利用提供了参考。

Objective To optimize the extraction of total flavonoids from Althaea officinalis,and to explore its anti-oxidation and anti-α-glucosidase activities in vitro.Methods Based on single-factor tests,the Box-Benhnken central combination design was used to determine the response surface with the ratio of liquid to solid,extraction time and ethanol concentration as variables.The total flavonoid was further purified by D101 macroporous resin,its anti-oxidation and anti-α-glucosidase activities were investigated in vitro,respectively.Results The optimization conditions included extraction twice,extraction temperature at 80℃,the ratio of solid to liquid at 1∶25(g/mL),ethanol concentration at 49.0%,and extraction for 2.0 h.Under these conditions,the extraction yield of total flavonoids reached 2.15%.The purity of the total flavonoids obtained by enrichment and purification was 53.62%.The in vitro biological activity showed that the total flavonoid of Althaea officinalis had obvious DPPH and ABTS free radical scavenging activities with the IC_(50) values of(8.36±0.06)μg·mL^(-1) and(8.45±0.14)μg·mL^(-1),respectively.Meanwhile,it exhibited significant inhibition onα-glucosidase in vitro with the IC_(50) value of(76.63±1.12)μg·mL^(-1).Conclusion The extraction of the total flavonoid of Althaea officinalis has been optimized for the first time,revealing antioxidation and inhibition onα-glucosidase in vitro,which provides a scientific reference for the development and utilization of the total flavonoid from Althaea officinalis.