双水相萃取分离红豆蛋白质

应用响应面法对双水相萃取分离红豆蛋白质的条件进行了优化.采用Plackett-Burman法对7个相关影响因素进行了评价,筛选出有显著正效应的pH值、NaCl质量分数和有显著负效应的温度3个因素;接着用最陡爬坡路径逼近最大响应区域,最后通过Box-Behnken设计法,利用Design-Expert软件进行二次回归分析,得到主要因素的最佳条件为:pH为7.5、NaCl质量分数为0.145％,萃取温度为33℃,在此优化萃取条件下,红豆蛋白萃取率达到50.27％,与预测值49.54％接近.

Isolation of red bean protein by aqueous two-phase system extraction

Response surface methodology was employed to optimize the extraction condition of red bean protein by aqueous two-phase system. Firstly, a Plackett-Burman design was used to evaluate the influence of 7 related factors. pH value and the mass fraction of NaCl influenced protein extraction positively while temperature did negatively. The path of steepest ascent was used to approach the optimal region of the extraction condition subsequently. Box-Behnken design was used to optimize the three critical factors mentioned above, the optimum levels and the relationships among these factors were found out by quadratic regression model equation with Design-Expert statistic methods，the optimal levels of the variables were determined as follows:pH value 7.5, NaCl 0.145%, extraction temperature 33℃, the protein extraction yield was 50.27%,which was in good agreement with the predicted one of 49.54%.