Rodríguez Mariela, García Fillería Susan F, Tironi Valeria A
Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA) - (CCT La Plata-CONICET, CICPBA, UNLP), 47 y 116, (1900) La Plata, Argentina.
Centro de Investigación y Desarrollo en Criotecnología de Alimentos (CIDCA) - (CCT La Plata-CONICET, CICPBA, UNLP), 47 y 116, (1900) La Plata, Argentina.
Food Res Int. 2020 Dec;138(Pt A):109735. doi: 10.1016/j.foodres.2020.109735. Epub 2020 Sep 22.
The effect of both the simulated gastrointestinal digestion conditions and the matrix over protein hydrolysis and antioxidant peptides generation was evaluated by comparing an in-house method with COST INFOGEST-based SGD protocols. The in-house protocol was used to digest amaranth protein isolate I (Id1), while the standardized method and a modified version (similar enzyme/substrate ratio than in our lab) were used to digest I and amaranth flour F (Id3 and Fd3, Id2 and Fd2). Protein hydrolysis degree (TNBS method) was similar for the three I digested (about 60%), but lower for F digested (45 and 34% for Fd2 and Fd3, respectively). The five digested obtained presented comparable protein solubility and only small differences in the polypeptide/peptide composition (SDS-PAGE, tricine-SDS-PAGE, gel filtration FPLC), similar antioxidant activity by the ORAC assay (IC values between 0.023 and 0.034 mg.mL) and some mild differences by the HORAC assay (IC values between 1.13 and 1.30 mg.mL for Id1, Fd2, and Fd3; 1.50 mg.mL for Id2; 1.61 mg.mL for Id3). All the FPLC fractions presented high ORAC activity, while only fractions between 0.43 and 3.5 kDa showed HORAC activity (due to peptide concentration). Differences in activity and potency among fractions were registered, especially for F digested. The modification of digestion conditions produced only small differences in the molecular composition but did not affect the proteolysis degree and the antioxidant activity in the case of digested from protein isolate. The presence of other components and changes in the digestion method had an impact on proteolysis, composition and antioxidant activity of flour digested.
通过将一种内部方法与基于COST INFOGEST的SGD方案进行比较，评估了模拟胃肠道消化条件和基质对蛋白质水解及抗氧化肽生成的影响。内部方案用于消化苋菜蛋白分离物I（Id1），而标准化方法及其修改版本（酶/底物比例与我们实验室相似）用于消化I和苋菜粉F（Id3和Fd3、Id2和Fd2）。三种消化后的I的蛋白质水解度（TNBS法）相似（约60%），但消化后的F的蛋白质水解度较低（Fd2和Fd3分别为45%和34%）。得到的五种消化产物具有相当的蛋白质溶解度，多肽/肽组成仅有微小差异（SDS-PAGE、tricine-SDS-PAGE、凝胶过滤FPLC），通过ORAC测定法具有相似的抗氧化活性（IC值在0.023至0.034 mg/mL之间），通过HORAC测定法存在一些微小差异（Id1、Fd2和Fd3的IC值在1.13至1.30 mg/mL之间；Id2为1.50 mg/mL；Id3为1.61 mg/mL）。所有FPLC级分均呈现高ORAC活性，而只有0.43至3.5 kDa之间的级分显示出HORAC活性（由于肽浓度）。记录了各组分之间活性和效力的差异，尤其是消化后的F。消化条件的改变仅在分子组成上产生微小差异，但对于从蛋白质分离物消化的情况，不影响蛋白水解度和抗氧化活性。其他成分的存在和消化方法的改变对消化后的面粉的蛋白水解、组成和抗氧化活性有影响。
