天水大红袍花椒籽黑色素的提取工艺优化及体外抗氧化活性分析

Optimization of Extraction Process of Melanin from Zanthoxylum bungeanum Seeds of Tianshui and Its Antioxidant Activity in Vitro

采用单因素实验结合响应面法优化天水大红袍花椒籽黑色素提取工艺,并对其抗氧化性进行评价。结果表明,最佳提取工艺为:NaOH浓度1.11 mol/L、提取温度59℃、料液比1:23 g/mL、提取时间2 h,在此条件下,天水大红袍花椒籽黑色素得率为7.60%±0.05%,与模型预测值(7.75%)接近,且其相对误差为0.66%,说明该模型回归项良好,拟合度好,优化后的工艺条件可行。体外抗氧化实验结果显示,质量浓度为1.0 mg/mL时,花椒籽黑色素对羟基自由基(·OH)、1,1-二苯基-2-三硝基苯肼自由基(DPPH·)以及2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸自由基(ABTS^(+)·)的清除率分别为66.07%±0.96%、61.27%±0.97%、62.19%±0.83%,说明天水大红袍花椒籽黑色素对·OH、DPPH·和ABTS^(+)·均具有良好的清除活性。

Single factor experiments combined with response surface methodology(RSM)was used to optimize the extraction process of melanin from Zanthoxylum bungeanum seeds of Tianshui and evaluated its antioxidant activity.The results showed that the optimal extraction conditions were determined as follows:NaOH concentration was 1.11 mol/L,extraction temperature was 59℃,solid-liquid ratio was 1:23 g/mL,extraction time was 2 h.Under the optimal process parameters,the yield of melanin from Zanthoxylum bungeanum seeds of Tianshui was 7.60%±0.05%,which was close to the predicted value(7.75%)of the model,and the relative error was 0.66%.It showed that the regression term and the fitting degree of the model were good,and the optimized process conditions were feasible.The results of antioxidant experiments in vitro showed that the scavenging rates of melanin from Zanthoxylum bungeanum seeds on hydroxyl radical(·OH),1,1-diphenyl-2-picrylhydrazyl(DPPH·),2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS^(+)·)reached 66.07%±0.96%,61.27%±0.97%,62.19%±0.83%,respectively,which indicated that melanin from Zanthoxylum bungeanum seeds of Tianshui had good scavenging activity on·OH,DPPH·and ABTS^(+)·.