Rohman Rakiba, Kar Rahul
Department of Chemistry, Dibrugarh University, Dibrugarh, Assam, 786004, India.
J Mol Model. 2018 Jun 19;24(7):165. doi: 10.1007/s00894-018-3701-0.
Polyphenolic antioxidants are an integral component of the present-day lifestyle due to growing environmental and pollution-related issues. Gallic acid (GA), a popular polyphenolic antioxidant, is widely distributed in different fruits and vegetables. It scavenges free radicals mostly through the hydrogen atom transfer (HAT) mechanism. The present work reports a fundamental understanding of the atom transfer involved in the antioxidant activity of GA in the presence of prototype oxyradicals. In this article, the behavior of GA in the presence of three prototype oxyradicals, based on the availability in biological systems, viz. hydroxyl (•OH), hydroperoxyl (•OOH), and methyl peroxyl (•OOMe) is studied. On radical scavenging, a sharp change in the structural, electronic, and thermodynamic properties of GA is observed. Finally, a new descriptor based on chemical hardness, which describes the stability of the antioxidant molecule during a HAT reaction, is also proposed. Graphical abstract The present work reports a fundamental understanding of the atom transfer involved in antioxidant activity of gallic acid in presence of prototype oxyradicals.
由于日益严重的环境和污染相关问题，多酚类抗氧化剂已成为当今生活方式中不可或缺的一部分。没食子酸（GA）是一种常见的多酚类抗氧化剂，广泛分布于不同的水果和蔬菜中。它主要通过氢原子转移（HAT）机制清除自由基。本研究报告了对在原型氧自由基存在下GA抗氧化活性中涉及的原子转移的基本理解。在本文中，基于生物系统中的可获得性，研究了GA在三种原型氧自由基，即羟基（•OH）、氢过氧自由基（•OOH）和甲基过氧自由基（•OOMe）存在下的行为。在自由基清除过程中，观察到GA的结构、电子和热力学性质发生了急剧变化。最后，还提出了一种基于化学硬度的新描述符，用于描述抗氧化剂分子在HAT反应过程中的稳定性。图形摘要 本研究报告了对在原型氧自由基存在下没食子酸抗氧化活性中涉及的原子转移的基本理解。
