Instituto Universitario de Ingenierı́a de Alimentos para el Desarrollo (IUIAD-UPV), Universitat Politècnica de València, Camino de Vera s/n, 46022 Valencia, Spain.
REDOLı́, Departamento de Quı́mica Inorgánica, Universitat de València, 46100 Burjassot, Valencia, Spain.
J Agric Food Chem. 2020 Jul 29;68(30):7964-7973. doi: 10.1021/acs.jafc.0c02407. Epub 2020 Jul 16.
Enzymatic browning is one of the main problems faced by the food industry due to the enzyme polyphenol oxidase (PPO) provoking an undesirable color change in the presence of oxygen. Here, we report the evaluation of 10 different azamacrocyclic compounds with diverse morphologies as potential inhibitors against the activity of PPO, both in model and real systems. An initial screening of 10 ligands shows that all azamacrocyclic compounds inhibit to some extent the enzymatic browning, but the molecular structure plays a crucial role on the power of inhibition. Kinetic studies of the most active ligand (L2) reveal a S-parabolic I-parabolic noncompetitive inhibition mechanism and a remarkable inhibition at micromolar concentration (IC = 10 μM). Furthermore, L2 action has been proven on apple juice to significantly reduce the enzymatic browning.
酶促褐变是食品工业面临的主要问题之一，这是由于多酚氧化酶（PPO）在氧气存在的情况下引发了不理想的颜色变化。在这里，我们报告了对 10 种不同形态的氮杂大环化合物作为潜在抑制剂对 PPO 活性的评估，包括模型系统和实际系统。对 10 种配体的初步筛选表明，所有氮杂大环化合物都在一定程度上抑制了酶促褐变，但分子结构对抑制能力起着至关重要的作用。最活跃配体（L2）的动力学研究表明，其存在 S-抛物线 I-抛物线非竞争性抑制机制，且在微摩尔浓度下表现出显著的抑制作用（IC=10 μM）。此外，L2 对苹果汁的作用已被证明可显著减少酶促褐变。
