响应面法优化的水飞蓟子可溶性蛋白质提取工艺

Optimization of Soluble Protein Extraction from Milk Thistle(Silybum marianum) Seed by Response Surface Methodology

采用单因素试验研究了提取液pH、温度、液固比和浸提时间对水飞蓟子脱脂粉末可溶性蛋白质提取率的影响。根据单因素试验结果,应用Box-Behnken中心组合试验设计原理,选取提取液pH(7.0、8.0和9.0)、温度(30、40和50℃)、液固比(40∶1、50∶1和60∶1,V/m,mL∶g)和浸提时间(90、120和150 min)4个因素为自变量,以水飞蓟子脱脂粉末可溶性蛋白提取率为响应值,建立回归模型,该模型相关系数R为0.843 2。响应面法优化提取工艺,得到的最佳提取条件为提取液pH 9.0,温度50℃,液固比60∶1,浸提时间90 min。在此条件下,水飞蓟子脱脂粉末可溶性蛋白质提取率达到最大预测值57.10%。方差分析表明,提取液pH、温度和液固比对蛋白质提取率有显著影响,而提取时间的影响不显著。验证试验进一步证实了模型和试验结果的可靠性。

The effects of pH,temperature,liquid-solid ratio and extraction time on soluble protein extraction from defatted milk thistle [Silybum marianum（L.）] seed were studied by single factor experiments.Using pH（7.0,8.0 and 9.0）,temperature（30,40 and 50 ℃）,liquid-solid ratio（40,50 and 60 mL/g） and extraction time（90,120 and 150 min） as independent variables and yield of soluble protein from defatted milk thistle seed as response value,regression model was built through Box-Behnken central composite design,of which the relative coefficient was 84.32%.According to response surface methodology（RSM） applied to optimize the extraction craft,the highest extraction rate which was prognosed as 57.10% could be obtained when pH,temperature,liquid-solid ratio and extraction time was 8.97,50 ℃,60 mL/g and 90 min,respectively.Analysis of variance（ANOVA） showed that pH,temperature and liquid-solid ratio had significant effect on extraction rate of soluble protein while extraction time had not.Confirmation tests were employed and validated reliability of the model and experimental results.