Sangiorgio Sara, Vidović Nikolina, Boschin Giovanna, Aiello Gilda, Arcidiaco Patrizia, Arnoldi Anna, Morelli Carlo F, Rabuffetti Marco, Recca Teresa, Scarabattoli Letizia, Ubiali Daniela, Speranza Giovanna
Department of Chemistry, University of Milan, Golgi 19, 20133 Milan, Italy.
Department of Pharmaceutical Sciences, University of Milan, L. Mangiagalli 25, 20133 Milan, Italy.
Foods. 2022 Sep 1;11(17):2667. doi: 10.3390/foods11172667.
A soy protein isolate was hydrolyzed with Alcalase®, Flavourzyme® and their combination, and the resulting hydrolysates (A, F and A + F) were ultrafiltered and analyzed through SDS-PAGE. Fractions with MW < 1 kDa were investigated for their ACE-inhibitory activity, and the most active one (A < 1 kDa) was purified by semi-preparative RP-HPLC, affording three further subfractions. NMR analysis and Edman degradation of the most active subfraction (A1) enabled the identification of four putative sequences (ALKPDNR, VVPD, NDRP and NDTP), which were prepared by solid-phase synthesis. The comparison of their ACE-inhibitory activities suggested that the novel peptide NDRP might be the main agent responsible for A1 fraction ACE inhibition (ACE inhibition = 87.75 ± 0.61%; IC50 = 148.28 ± 9.83 μg mL−1). NDRP acts as a non-competitive inhibitor and is stable towards gastrointestinal simulated digestion. The Multiple Reaction Monitoring (MRM) analysis confirmed the presence of NDRP in A < 1 kDa.
用碱性蛋白酶、风味酶及其组合对大豆分离蛋白进行水解，所得水解产物（A、F和A + F）经超滤后通过SDS-PAGE进行分析。对分子量小于1 kDa的组分进行ACE抑制活性研究，并通过半制备RP-HPLC对活性最高的组分（A < 1 kDa）进行纯化，得到另外三个亚组分。对活性最高的亚组分（A1）进行NMR分析和埃德曼降解，鉴定出四个假定序列（ALKPDNR、VVPD、NDRP和NDTP），这些序列通过固相合成制备。对它们的ACE抑制活性进行比较表明，新型肽NDRP可能是A1组分ACE抑制作用的主要成分（ACE抑制率 = 87.75 ± 0.61%；IC50 = 148.28 ± 9.83 μg mL−1）。NDRP作为一种非竞争性抑制剂，对胃肠道模拟消化具有稳定性。多反应监测（MRM）分析证实了A < 1 kDa中存在NDRP。
