Bikaki Maria, Kuhnert Nikolai
Department of Life Sciences and Chemistry, Jacobs University Bremen, Bremen, Germany.
Front Nutr. 2021 Jul 22;8:663233. doi: 10.3389/fnut.2021.663233. eCollection 2021.
In this contribution we investigate the thermal degradation of dietary-relevant pentapeptides. Most unsaturated lipids degrade by the well-known peroxidation mechanism. Here we show a degradation mechanism of peptides analogous to lipid peroxidation, forming a series of novel degradation products with possible toxicological relevance. At elevated temperatures above 180°C, pentapeptides with an N-terminal phenylalanine moiety react a debenzylation to form 1,2-dicabonyl compounds, replacing the N-terminal primary amine. We propose a radical-based reaction mechanism that leads a common peroxoaminal intermediate to two distinct types of reaction products with a terminal α-1,2 diamide or an α-amide-aldehyde functionality.
在本论文中，我们研究了与饮食相关的五肽的热降解情况。大多数不饱和脂质通过著名的过氧化机制降解。在此，我们展示了一种类似于脂质过氧化的肽降解机制，形成了一系列可能具有毒理学相关性的新型降解产物。在高于180°C的温度下，带有N端苯丙氨酸部分的五肽发生脱苄基反应，形成1,2 - 二羰基化合物，取代N端伯胺。我们提出了一种基于自由基的反应机制，该机制导致一个共同的过氧氨基中间体生成两种不同类型的反应产物，一种具有末端α - 1,2二酰胺官能团，另一种具有α - 酰胺 - 醛官能团。
