有效降低速溶豆奶粉(ISMP)的致敏性对于扩大其应用具有实用价值。本研究采用单因素实验和响应面法对ISMP酶解工艺进行了优化,联合血清学分析,细胞免疫模型,生物信息学工具,和多种光谱技术来研究alcalase水解对致敏性的影响,空间构象,和ISMP的线性表位。在最优过程下,特异性IgE和IgG1结合能力以及诱导alcalase水解ISMP细胞脱粒的变应原活性降低了(64.72±1.76)%,(56.79±3.72)%,和(73.3±1.19)%,分别为(P<0.05)。此外,速溶豆奶粉水解物(ISMPH)的空间构象发生变化,包括表面疏水性降低,一个较弱的酰胺II谱带峰,较低的α-螺旋和β-折叠的含量,以及增强的无规卷曲含量。此外,主要大豆过敏原的线性表位,9来自大豆球蛋白,13来自β-伴大豆球蛋白,可以被alcalase水解定向破坏。总的来说,初步阐明了alcalase水解降低ISMP体外致敏性的构效机制。为ISMP脱敏研究的突破提供了新的研究方向,为揭示alcalase酶解降低ISMP致敏性的潜在机理提供了理论依据。
Effective reduction of the allergenicity of instant soy milk powder (ISMP) is practically valuable for expanding its applications. This study optimized the enzymolysis technology of ISMP using single-factor experiments and response surface methodology, combined serological analysis, cellular immunological models, bioinformatics tools, and multiple spectroscopy techniques to investigate the effects of
alcalase hydrolysis on allergenicity, spatial conformation, and linear epitopes of ISMP. Under the optimal process, special IgE and IgG1 binding abilities and allergenic activity to induce cell degranulation of
alcalase-hydrolyzed ISMP were reduced by (64.72 ± 1.76)%, (56.79 ± 3.72)%, and (73.3 ± 1.19)%, respectively (P < 0.05). Moreover, the spatial conformation of instant soy milk powder hydrolysates (ISMPH) changed, including decreased surface hydrophobicity, a weaker peak of amide II band, lower contents of α-helix and β-sheet, and an enhanced content of random coil. Furthermore, the linear epitopes of major soy allergens, 9 from glycinin and 13 from β-conglycinin, could be directionally disrupted by
alcalase hydrolysis. Overall, the structure-activity mechanism of
alcalase hydrolysis to reduce ISMP allergenicity in vitro was preliminarily clarified. It provided a new research direction for the breakthrough in the desensitization of ISMP and a theoretical basis for revealing the potential mechanism of
alcalase enzymolysis to reduce the allergenicity of ISMP.