【摘要】 酶法水解大豆蛋白可以生产多种生物活性肽,但在酶解过程中肽段的二次聚集会产生不溶沉淀,降低蛋白质利用率。研究了pH偏移对大豆蛋白酶解聚集体解聚的影响。结果表明:Alcalase碱性蛋白酶酶解大豆蛋白获得的不溶沉淀,是以疏水相互作用为主要分子间作用力的大豆肽聚集体;pH偏移赋予的静电斥力能促使大豆肽聚集体解聚和重排,大豆肽蛋白质利用率从74%(pH 7)增加到85%(pH 12),并将大豆肽的平均粒径由243 nm减小至103 nm;同时,pH偏移使疏水性氨基酸在不溶肽聚集体中积累,增加二级结构中的无规则卷曲含量,但不影响不溶肽聚集体的相对分子质量分布。因此,pH偏移技术可安全有效地促使大豆肽不溶聚集体解聚。更多还原

【Abstract】 The enzymatic hydrolysis of soybean protein produces a variety of bioactive peptides. However, due to the self-aggregation of peptides in the enzymatic hydrolysis process, insoluble aggregates are produced and protein utilization rate is reduced. The pH-shift dissolving the soybean peptide aggregates was studied. The results showed that the insoluble precipitate obtained by Alcalase enzymatic hydrolysis of soybean protein was peptide aggregates with hydrophobic interaction as the main intermolecular force. The charge repulsion provided by the pH-shift technology promoted the depolymerization and rearrangement of the soybean peptide aggregation system. The soybean peptide protein utilization rate increased from 74% at pH 7 to 85% at pH 12, and the average particle size of soy protein peptides reduced from 243 nm to 103 nm. At the same time, pH-shift caused hydrophobic amino acids to accumulate in insoluble aggregates, increasing the random coil content in the secondary structure, but did not affect the relative molecular weight distribution of the insoluble aggregates. Therefore, the pH-shift technology could safely and effectively promote the depolymerization of insoluble aggregates of soybean peptides.更多还原