【摘要】 采用超声技术从田基黄中提取活性物质。运用响应面法确定超声提取田基黄的最佳条件。运用单因素试验选取三个自变量。采用Box-Behnken设计评价这三个自变量对总黄酮和总多酚提取、DPPH和ABTS+活性清除的影响。通过方差分析显示,二次模型对反应的贡献率具有统计学意义。运用响应面法进行最优化研究,并用数学模型绘制出三维响应面。通过结合反应得出最佳试验条件:超声时间48.89 min,乙醇浓度63.72%,超声温度66.92℃。总黄酮值为105.06 mg RE/g DW,总多酚值为51.75 mg GAE/g DW,%DPPHsc为58.81%,%ABTSsc为64.99%。在最佳试验条件下,试验值与方差分析预测值一致。结果表明,采用四个模型和响应面法优化总黄酮和总多酚的提取、DPPH和ABTS+活性清除是切实可行的。更多还原

【Abstract】 In this study,ultrasonication was employed to extract bioactive components from Hypericum. japonicum Thunb.ex Murray(Hypericaceae). The optimal conditions for ultrasonic extraction of Hypericaceae were determined by response surface methodology. Three independent variables were chosen based on single factor tests. Box-Behnken design was applied to evaluate the effects of three independent variables( ultrasonic time,ethanol concentration,ultrasonic temperature) on the extraction yield of total flavonoid compound(TFC),total phenolic compound(TPC) and their scavenging activity to DPPH and ABTS+free radicals. The analysis of variance(ANOVA) showed that the contribution of quadratic model was significant for the responses. The 3D response surfaces were plotted from the mathematical model. The optimized extraction conditions based on combination responses were as follows:ultrasonic time of 48. 89 min,ethanol concentration of 63. 72% and ultrasonic temperature of 66. 92 ℃. Under the optimized condition,TFC,TPC,% DPPHsc and% ABTSsc were determined to be 105. 06 mg RE /g DW,51. 75 mg GAE /g DW,58. 81% and 64. 99%,respectively.The experimental values agreed with the predicted ones by analysis of variance( AVOVA). It indicated high fitness of four models used and the success of using response surface methodology for the optimization of the extraction conditions.更多还原