辣木叶酶法水解提取蛋白质工艺优化

为了优化纤维素酶与果胶酶水解提取辣木叶中蛋白质的提取工艺，以提取率为考察指标，运用单因素与正交试验研究了酶解温度、加酶量、pH、底物质量浓度与酶解时间5个因素对辣木叶蛋白质提取率的影响。结果表明:纤维素酶各因素对辣木叶蛋白质提取率影响的主次顺序为:酶解温度 > 底物质量浓度 > pH > 酶解时间 > 加酶量，最佳工艺条件为:酶解温度40℃、加酶量800 U/L、酶解pH5.0、底物质量浓度7.0 g/L、酶解时间70 min，在此条件下的提取率达到了43.85%。果胶酶各因素对辣木叶蛋白质提取率影响的主次顺序为:加酶量 > 底物质量浓度 > 酶解时间 > 酶解温度 > pH，最佳工艺条件为:酶解温度50℃、加酶量1400 U/L、pH4.0、底物质量浓度9.0 g/L、酶解时间50 min，提取率达到了32.26%。纤维素酶与果胶酶各因素对辣木叶蛋白质提取率的影响均达到了极显著水平（P<0.01）。在最佳工艺条件下，纤维素酶水解辣木叶提取蛋白质的效果优于果胶酶。

Process Optimization of Protein Extraction from Moringa oleifera Leaf by Enzymatic Hydrolysis

In order to optimize the extraction process of cellulase and pectinase hydrolysis to extract protein from Moringa oleifera leaf,the effects of five processing conditions on the extraction rate were explored by single factor and orthogonal array design methods.Results showed that the effect of five processing conditions on the extraction rate of Moringa oleifera leaf protein with cellulase was in the descending order of reaction temperature,substrate concentration,pH,hydrolysis time and enzyme dosage.The optimal hydrolysis conditions were found to be reaction at 50℃and pH5.0 for 70 min with a substrate concentration of 7.0 g/L and an enzyme dosage of 800 U/g,the extraction rate reached 43.85%.In the case of hydrolysis with pectinase,the decreasing order of five processing conditions was enzyme dosage,substrate concentration,hydrolysis time,temperature,and pH,and their optimal levels which provided maximum extraction rate as high as 32.26%were determined as 1400 U/L,9.0 g/L,50 min,50℃,and 4.0,respectively.In both cases,the effect of five processing conditions on the extraction rate reached up to a significant level(P<0.01).Under the optimized hydrolysis conditions,cellulase was superior to pectinase in extracting proteins from Moringa oleifera leaf.