微波辅助提取油橄榄多酚及抗氧化活性研究

Study on the microwave- assisted extraction and antioxidant capacity of polyphenols from olive fruits

以油橄榄鲜果为实验材料,采用响应面法优化微波辅助提取油橄榄多酚的工艺,并分析多酚提取液的抗氧化活性。在单因素实验的基础上,根据Box-Benhnken实验设计原理建立二次回归模型,确定最佳提取工艺条件为料液比1∶23(g/m L)、微波时间48 s、微波功率490 W,油橄榄多酚实际平均得率为6.9659 mg/g,与预测值的相对误差为1.12%。油橄榄多酚提取液对DPPH自由基和羟基自由基的最大清除率分别为87.85%、68.12%,其IC50分别为0.055、0.188 mg/m L,对Cu2+的最大螯合率为54.18%,半螯合浓度为0.277 mg/m L。

Response surface analysis methodology （RSM）was applied to optimize the microwave- assisted extraction conditions of polyphenols from fresh olive fruits, furthermore, the study investigated the antioxidant activity of polyphenols extracts.Based on single factor experiments,a quadratic regression model was established according to the Box-Behnken experimental design.The optimum microwave-assisted conditions were material- liquid ratio 1：23（ g/mL）, microwave time 48 s, microwave power 490 W.Validation experiments were carried out at the optimum microwave-assisted conditions,the average yield of polyphenols was 6.9659 mg/g,the relative error between experimental values and the predicted value was 1.12%. It showed that the optimization process was feasible.The maximum inhibition percentage of DPPH and hydroxyl radical of polyphenol extracts were 87.85% and 68.12% ,respectively.The IC50 value were 0.055 mg/mL and 0.188 mg/mL, respectively. In addition, the maximum chelating rate of Cu2＋ was 54.18%, the Cu2＋ chelating concentration in half of polyphenols extracts was 0.277 mg/mh