响应面法优化提取无花果干果中多酚和总黄酮物质及其抗氧化活性

利用响应面法优化无花果干果中多酚和黄酮物质的提取工艺,并分析其体外抗氧化活性。在单因素实验基础上,根据Box-Behnken试验设计对提取条件(乙醇体积分数、超声温度、超声时间、料液比)进行分析与优化,从而考察其对多酚及黄酮提取量的影响并进一步研究无花果干果提取物的抗氧化活性。结果显示,最佳工艺参数为:乙醇体积分数60%,超声温度51 ℃,超声时间52 min,料液比1:45 (g/mL)。在此工艺条件下,多酚的提取量为(2.72±0.37) mg/g,总黄酮的提取量为(20.89±0.57) mg/g。与V_C进行抗氧化活性比较发现,在多酚质量浓度(2.50 mg/g)相同条件下,无花果干果中多酚提取物的还原能力、清除羟自由基率(最高为95.54%)以及清除DPPH自由基率(最高为66.73%)均高于V_C,清除超氧阴离子自由基率(最高为35.15%)低于V_C。在黄酮质量浓度(10.60 mg/g)相同条件下,无花果干总果黄酮提取物各抗氧化指标均低于V_C。另外,人工模拟胃肠液处理对无花果干果提取物抗氧化活性的影响实验发现,经人工胃液处理后,提取液的还原能力和羟自由基清除能力明显著升高,而DPPH自由基和超氧阴离子自由基清除能力明显降低,经人工肠液处理后,相应的还原能力和超氧阴离子自由基清除能力明显升高,而DPPH和羟自由基清除能力明显下降。

Optimization of Extraction of Polyphenols and Total Flavonoids from Dried Figs by Response Surface Methodology and Antioxidant Activity Analysis

Response surface analysis method was applied to optimize the extraction process of dried figs,and evaluate the antioxidant activities. On the basis of single-factor test,the extraction conditions(ethanol concentration,extraction temperature,extraction time and material/liquid ratio)were analyzed and optimized by the Box-Behnken design,and researched the antioxidant activity of dried figs extract. Results showed that,the optimal extraction parameters were found as follows:Ethanol concentration 60%,extraction temperature 51 ℃,extraction time 52 min,material/liquid ratio 1:45 (g/mL). The yield of polyphenols was(2.72±0.37) mg/g,and the yield of total flavonoids was(20.89±0.57) mg/g under these conditions. The antioxidant activities were evaluated and compared with V_C. The results showed that,the antioxidant activity of total reducing power,hydroxyl(highest:95.54%)and DPPH free radical scavenging(highest:66.73%)abilities of polyphenols was higher than V_C,but the super-oxide anion free radical scavenging(highest:35.15%)abilities was lower than V_C,while the antioxidant activity of total flavonoids was lower than V_C. The present study also found that after treatment with artificial gastric fluid,the total reducing power and hydroxyl free radical scavenging abilities was significantly increased but the DPPH and the super-oxide anion free redical scavenging abilities was significantly decreased. After treatment with artificial intestinal fluid,the total reducing power and the super-oxide anion free redical scavenging abilities was significantly increased but the DPPH and hydroxyl free radical scavenging abilities was significantly decreased.