Radical scavenging and chemical repair of rutin observed by pulse radiolysis: as a basis for radiation protection.

Radical scavenging and chemical repair of rutin observed by pulse radiolysis: as a basis for radiation protection. Free Radic Res. 2019 Sep 12;:1-191 Authors: Yu H, Yamashita S Abstract Pulse radiolysis was conducted to investigate several fundamental reactions of a natural flavonoid, rutin, and its glycosylated form (αG-rutin) as a basis for their radiation protection properties; the reactions with •OH (radical scavenging) and dGMP radical, dGMP• (chemical repair), which was used as a model of initial and not yet stabilized damage on DNA. Three absorption peaks were commonly seen in the reactions of the flavonoids with •OH, showing that their reactive site is the common structure, ie aglycone. One among the three peaks was attributed to the flavonoid radical produced as a result of the removal of a hydrogen atom. The same peak was found in their reactions with dGMP•, showing that dGMP• is chemical repaired by obtaining a hydrogen atom supplied from the flavonoids. Such a spectral change due to the chemical repair was as clear as never reported. The rate constants the chemical repair reaction were estimated as (9 ± 2) × 108 M-1 s-1 and (6 ± 1) × 108 M-1 s-1 for rutin and αG-rutin, respectively. The rate constants of the radical scavenging reactions toward •OH were estimated as (1.3 ± 0.3) × 1010 M-1 s-1 and (1.0 ± 0.1) × 1010 M-1 s-1 for rutin and αG-rutin, respectively. In addition, there was no obviou...
Source: Free Radical Research - Category: Research Tags: Free Radic Res Source Type: research