State Key Laboratory of Food Nutrition and Safety, Key Laboratory of Food Nutrition and Safety, Ministry of Education, College of Food Science and Engineering, Tianjin University of Science and Technology, Tianjin Economic-Technological Development Area (TEDA), Tianjin, China.
Dingzheng Xinxing Biotechnology (Tianjin) Co., Ltd., Taifeng Road, TEDA, Tianjin, China.
J Food Sci. 2022 Jul;87(7):3107-3116. doi: 10.1111/1750-3841.16189. Epub 2022 May 31.
Enzymatic hydrolysis is the most commonly used method to reduce the antigenicity of milk protein, but free protease is unstable and difficult to recycle after application. In this study, alcalase and neutrase were selected for immobilization on the modified magnetic Fe O nanoparticles. The reusability of the immobilized enzyme was 68.23% of the total starting activity after 5 recycling batches. The optimal hydrolysis conditions were an enzyme to substrate ratio of 6000 U/g and reaction at 50℃ and pH 8.5 for 3 h. Under these conditions, 22.76% hydrolysis of hydrolysate was achieved, and the antigenicity reduction rates of β-lactoglobulin and casein were 21.34% and 30.89%, respectively. In addition, 82.75% of the hydrolysate had a molecular weight less than 1 kDa, and free amino acids represented 13.65% of the sample. This result showed that the hydrolysis with immobilized enzyme was similar to that with free enzyme and the immobilized enzyme could be applied to produce hypoallergenic hydrolysate. PRACTICAL APPLICATION: Reduces milk protein allergenicity.
酶解是降低牛奶蛋白抗原性最常用的方法，但游离蛋白酶在应用后不稳定且难以回收。本研究选择碱性蛋白酶和中性蛋白酶固定在改性磁性 FeO 纳米粒子上。固定化酶经过 5 次回收循环后，总起始活性的重复使用率为 68.23%。最佳水解条件为酶与底物比为 6000 U/g，在 50℃和 pH8.5 下反应 3 h。在此条件下，水解产物的水解度达到 22.76%，β-乳球蛋白和酪蛋白的抗原性降低率分别为 21.34%和 30.89%。此外，82.75%的水解产物的分子量小于 1 kDa，游离氨基酸占样品的 13.65%。结果表明，固定化酶水解与游离酶水解相似，固定化酶可用于生产低致敏水解产物。
