物理化学性质与和醇类似物中抗氧化活性的相关性
R Bernadett Vlocskó1, Maxim Mastyugin1, Béla Török1
1Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd, Boston, MA, 02125, USA.
Scientific reports
|January 2, 2025
概括
硫和具有显著的抗氧化活性,其结构特征影响了它们的激素清除潜力. 溶剂效应决定了原子转移或单电子转移机制是否占主导地位.
科学领域:
- 药用化学 医学化学
- 计算化学计算化学
- 生物化学 生物化学
背景情况:
- 活性氧和物种 (ROS,RNS) 的氧化应激与衰老和阿尔茨海默氏症和癌症等疾病有关.
- 和多是众所周知的抗氧化剂,但结构相似的类尽管具有激素清除潜力,但研究较少.
研究的目的:
- 评估和硫的结构特征如何影响它们的抗氧化活性.
- 确定关键的物理化学性质,控制这些化合物的激素清除效率.
主要方法:
- 密度功能理论 (DFT) 的计算被用来确定气相和水相中的17种/类相的物理化学性质.
- 使用ABTS和DPPH激素清除试验来评估实验性抗氧化剂活性.
- 计算属性之间的相关性 (BDE,HOMO/LUMO能量等) 和实验活动进行了调查.
主要成果:
- 几种醇和醇类似物显示出抗氧化活性优于参考Trolox.
- DFT的计算表明,较低的BDE值有利于气相中的原子转移 (HAT) 机制.
- 在水溶液中,减少的质子亲和力 (PA) 表明单个电子转移之后的质子转移 (SPLET) 机制占主导地位.
结论:
- 结构特征显著影响和硫的抗氧化能力.
- 主要的激素清除机制 (HAT与SPLET) 取决于相 (气相与水相).
- 这项研究强调了硫作为具有可调节性质的有前途的抗氧化化合物.
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