摘要
以脱酚棉籽为原料,对比碱溶酸沉法和酶水解-超声波辅助碱溶酸沉法对棉籽蛋白提取率的影响发现,酶解和超声辅助可以显著增加碱溶酸沉的蛋白提取率。在酶水解-超声波辅助碱溶酸沉提取蛋白的基础上,利用糖化酶纯化所提取的蛋白粗品,并在单因素试验的基础上采用正交试验优化棉籽蛋白纯化工艺,得到高纯棉籽蛋白制备的最佳工艺条件为:酶解温度60℃,酶解pH 4.5,酶解时间120 min,糖化酶用量0.4%,液料比9︰1(mL/g)。验证试验表明,利用该工艺两次纯化棉籽蛋白所得的纯化产品蛋白质含量可达93.10%。采用SDS-PAGE对纯化后的棉籽分离蛋白亚基相对分子质量分布进行分析,结果表明,纯化产品中蛋白质亚基相对分子质量主要为55.1 k Da与47.5 k Da。该研究可为棉籽蛋白在食品工业中的应用提供理论参考。
By comparing the effects of conventional alkali soluble acid-isolation method and enzyme hydrolysis-ultrasonic assisted alkali soluble acid sinking method on the extraction rate of dephenolized cottonseed protein, it was found that enzymatic and ultrasonic assistance could significantly improve the protein extraction of alkali soluble acid-isolation method. On the basis of the protein extraction associated with enzyme hydrolysis and ultrasonic treatment, the crude protein was further purified by glucoamylase. Orthogonal test were applied to optimize the optimal purification parameters on the basis of single factor experiments. The optimal process conditions were established as followings： enzymolysis temperature 60 ℃, pH 4.5, hydrolysis time 120 min, the amount of enzyme 0.4%, and ratio of liquid to solid 9 ： 1 （mL/g）. Verification test showed that the highest content of purified cottonseed protein could reach 93.10% after two times purification. Relative molecular weight （MW） distribution of protein subunit in purified cottonseed protein was analyzed by SDS-PAGE method. SDS-PAGE test showed that the major relative MW were 55.1 kDa and 47.5 kDa, which indicated that it was feasible to prepare high purity protein with the purification method mentioned. The present work could provide practical guidelines for the application of cottonseed protein in food industry.
出处
《食品工业》
CAS
北大核心
2016年第9期75-79,共5页
The Food Industry
基金
国家粮食公益性行业科研专项"粮油加工技术与装备开发应用"(201313012)
关键词
棉籽蛋白
糖化酶
纯化
SDS-PAGE
酶水解-超声波辅助提取
cottonseed protein
glucoamylase
purification
SDS-PAGE
enzyme hydrolysis-ultrasonic assisted alkali soluble acid sinking method
