碱性蛋白酶和亚硫酸钠水解菜籽粕制取菜籽多肽的研究

本文研究碱性蛋白酶Alcalase直接水解菜籽粕制取菜籽多肽,试验反应时添加亚硫酸钠的影响及使用膜分离技术去除产物中的硫代葡萄糖苷。结果表明,Na2SO3通过对蛋白质分子中的二硫键的断裂作用及对碱性蛋白酶抑制剂的影响,可提高碱性蛋白酶的活性,使得到的菜籽多肽的分子质量分布发生变化,小分子的多肽比例相应增加。结果同时显示,膜分离可有效减少或除去硫代葡萄糖苷等抗营养因子,使用截留分子质量3000 u的膜对菜籽粕酶解产物进行超滤和透析过滤,当超滤浓缩因子和透析过滤体积倍数均为2时,产物的硫代葡萄糖苷含量从1.36 mg/g降低到0.39 mg/g。

Study on Preparation of Peptides by Hydrolysis of Rapeseed Meal with Alcalase in the Presence of Sodium Sulfite

Peptides were prepared directly by hydrolysis of rapeseed meal with Alcalase. Effects of sodium sulfite on proteolysis and separation of glucosinolate by membrane processing were investigated. Results indicate that sodium sulfite can increase the activity of Alcalase and change the molecular weight distribution of hydrolysates with more proportion of smaller peptides by disulfide bond cleavage in protein molecules and by possible impact on Alcalase inhibitors. Results also show that glucosinolate can be reduced or eliminated by membrane processing. When hydrolysate of rapeseed meal was ultrafiltrated and diafiltrated with a membrane of 3 kilodaltons molecular weight cut-off and with both the concentration factor of ultrafiltration and the diavolume of diafiltration of 2, the glucosinolate content of the retentate was decreased to 0.39 mg/g from 1.36 mg/g in the hydrolysate.