牛蒡根多酚和黄酮超高压提取工艺优化及体外抗氧化活性

Optimization of Process for Ultra High Pressure-Assisted Synchronous Extraction of Polyphenols and Flavones from Burdock Roots and Their Antioxidant Activity

对牛蒡根多酚与黄酮的超高压提取工艺和抗氧化活性进行研究。在单因素试验基础上,用Box-Behnken设计,采用三因素三水平的响应面分析方法优化牛蒡根多酚和黄酮提取工艺。依据数据的模型拟合和回归分析,确定乙醇体积分数和料液比是影响多酚和黄酮得率的重要因素,并最终获得超高压辅助提取牛蒡根多酚和黄酮的最佳工艺条件为:乙醇体积分数75%、料液比1∶28(g/m L)、压力236 MPa、保压时间9 min、室温提取,采取该工艺得到牛蒡根多酚得率为(107.83±1.148)mg/g,黄酮得率为(21.27±0.950)mg/g。体外抗氧化实验结果表明:牛蒡根多酚提取物具有较强的金属离子螯合能力(IC50值为(1.393±0.011)mg/m L)、DPPH自由基清除能力(IC50值为(0.309±0.007)mg/m L)和铁离子还原能力。

The ultra high pressure（UHP）-assisted simultaneous extraction and antioxidant activity of total phenols and flavones from burdock roots were studied.To optimize the extraction process,the response surface methodology with three factors at three levels was adopted on the basis of single factor experiments.Model fitting and regression analysis of experimental data showed that two significant factors which influence total phenol and flavone yields were ethanol concentration and solid-to-solvent ratio.The optimal extraction conditions were determined as follows:75%ethanol as extraction solvent,solid-to-solvent ratio 1:28（g/mL）,extraction pressure 236 MPa,pressure holding time 9 minutes,and room temperature.Under these optimal conditions,the yield of total phenols and flavones from burdock reached（107.83 ±1.148） and（21.27 ± 0.950） mg/g respectively.The polyphenols extracted from burdock showed strong ferric ions chelating ability(IC50（1.393 ± 0.011） mg/mL),2,2-diphenyl-l-picrylhydrazyl（DPPH） radical-scavenging activity(IC50（0.309±0.007） mg/mL) and ferric ions reducing power.