在 (R) -3-基酸盐和基基之间的反应的可行性
Peter A C McPherson1, Ruaidhrí MacDonnell2, Ben M Johnston3
1School of Pharmacy & Pharmaceutical Science, Ulster University, Cromore Road, Coleraine BT52 1SA, UK. p.mcpherson@ulster.ac.uk.
Physical chemistry chemical physics : PCCP
|September 16, 2025
概括
(R) -3-基酸盐 (HB-) 有效地清除由太空辐射产生的有害基基 (HO ̇). 这种体为宇航员提供了一个有前途的抗氧化剂策略,以减轻辐射诱导的细胞损伤.
科学领域:
- 生物化学 生物化学
- 计算化学计算化学
- 天体化学是天体化学.
背景情况:
- 太空辐射产生反应性氧物种 (ROS),如基激素 (HO ̇),导致细胞损伤和死亡.
- 外源抗氧化剂被探索为对抗辐射诱导的细胞效应的对策.
研究的目的:
- 研究 (R) -3-基酸盐 (HB−) 和基基 (HO ̇) 之间的反应动力学和反应机制.
- 评估HB-作为内源性抗氧化剂对抗太空辐射损伤的潜力.
主要方法:
- 使用计算化学方法 (SMD/M062X/6-311++G(d,p)) 来建模反应.
- 计算的双分子速率常数和反应通道贡献.
主要成果:
- HB−和HO ̇之间的反应具有很高的双分子速率常数 (6.20 × 109 dm3 mol−1 s−1).
- 从基基C-H键中抽取原子是主要的反应途径 (Γ ≈ 30%).
- 在饮食症中,HB− 显示了较短的HO ̇ 半衰期,与酸盐相比.
结论:
- (R) -3-基酸盐对基基具有显著的反应性.
- HB− 是一种可行的内源性抗氧化剂策略,可以减轻太空飞行期间电离辐射对细胞的影响.
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