响应面法优化夏枯草中总黄酮提取工艺及其抗氧化活性分析

Optimization of Extraction Process of Total Flavonoids from Prunellae Spica by Response Surface Methodology and Analysis of Its Antioxidant Activity

目的考察夏枯草中总黄酮提取量的影响因素,并检验其总黄酮的体外抗氧化活性,优选夏枯草中总黄酮提取工艺。方法采用单因素考察法及响应面法,以乙醇体积分数、液料比、提取时间为考察因素,以总黄酮提取量为评价指标,采用紫外可见分光光度法测定夏枯草中总黄酮的提取量。以DPPH自由基法、ABTS+·自由基法测定总黄酮的自由基清除活性。结果夏枯草中总黄酮最佳提取工艺为乙醇体积分数55%,提取5 h,提取物液料比44∶1(V/m);总黄酮的质量浓度在0.02~0.12 mg/mL范围内对DPPH自由基和ABTS+·自由基的最大清除率分别为70%和82%,分别低于维生素C的84%和90%。结论该提取工艺简便可行,可用于工业化大生产。

Objective To investigate the factors affecting the extraction amount of total flavonoids from Prunellae Spica,to test the antioxidant activity of total flavonoids in vitro,and to optimize the extraction process of total flavonoids from Prunellae Spica.Methods The extraction amount of total flavonoids from Prunellae Spica was determined by ultraviolet(UV)-visible(Vis)spectrophotometry with ethanol volume fraction,liquid-solid ratio and extraction time as the investigation factors and with the extraction amount of total flavonoids as the evaluation index.The free radical scavenging activities of total flavonoids were determined by DPPH free radical method and ABTS+·free radical method.Results The optimum extraction process of total flavonoids from Prunellae Spica was as follows:the volume fraction of ethanol was 55%,the extraction time was 5 h,and the liquid-solid ratio was 44∶1(V/m).When the mass concentration of total flavonoids was in the range of 0.02-0.12 mg/mL,the maximum scavenging rates of DPPH free radical and ABTS+·free radical were 70%and 82%,which were lower than 84%and 90%of vitamin C,respectively.Conclusion The extraction process is simple and feasible,which can be used in industrial production。