Scavenger of OH radical

However, in Ar and H2 atmospheres, the formation of H2O2 was arrested due to the scavenging of OH radicals by the hydrogen [75] producing only pure copper nanoparticles. Thus argon and hydrogen mixture produced even more H radicals and reduced Cu2+ ions to Cu+ as a consequence of sonication in the aqueous... 

The hydrated electrons were produced in a matrix consisting of triply distilled water, 0.2 M in tert. butyl alcohol (for rapid scavenging of OH-radicals), and acetate buffer, by 4—40 nsec single pulses of 15 MeV electrons. 

In contrast, OFI radicals, which are formed concomitantly in water radiolysis [27], are able to oxidize the ions or the atoms into a higher oxidation state and thus to counterbalance the previous reductions. For that reason, the solution is generally added with a scavenger of OH radicals. Among various possible molecules, the preferred ehoiee is for solutes whose oxidation by OH yields radicals, which are unable to oxidize the metal... 

Akaike et al. have examined the neuroprotective properties of serofendic acid, a substance isolated from serum. The compound was found to protect neuronal cells from both glutamate and NO. This was attributed to the scavenging of OH radicals (from the decomposition of ONOO-) rather than NO itself.320 Indeed, Ueda and colleagues have demonstrated the formation of both NO and OH in neuronal cells upon stimulation of the NMDA receptor.321 These workers also trapped lipid radicals in the brains of rats undergoing seizures induced by the stimulation of a subset of glutamate receptors with kainic acid. Polyphenols have been shown to exacerbate the neurotoxicity of NO.322... 

A reduction and activation of HjOj by other one-electron donors, like semiquinones, has also to be considered. This follows from a study of the ethylene production from methionine in the presence of pyridoxal phosphate, a reaction characteristic for OH radicals or for Fenton-type oxidants. The ethylene production in the presence of dioxygen, anthraquinone-2-sulfonate, and an NADPH-generating system in phosphate buffer pH 7.6 was inhibited by SOD and by catalase, but stimulated by scavengers of OH radicals, like 0.1 mM mannitol, a-tocopherol, and formiate... 

The insulin producing P cells of the pancreas are selectively destroyed by alloxan, which is reduced there to dialurate. Isolated pancreatic islets of mice were protected against the action of alloxan, by BESOD, by catalase, and by scavengers of OH radicals. A treatment of rat pancreatic islets with SOD, catalase or diethylenetriaminepenta-acetate attenuated the effect of alloxan, suggesting again a participation of OH radicals... 

The Effects of Added Ce3+ and Br" Ions. Ce3+ and Br" ions are good scavengers of OH radicals and are likely to interfere with the phenomena... 

Experiments on determination of H2 yield in presence of some scavengers of OH radicals permitted the yield of Reaction b to be found, that proved equal to 0.35-0.4 (II). 

In contrast, OH" radicals can oxidize the ions or the atoms to a higher oxidation state and can thus counterbalance the previous reductions (Eqs. 2 and 3). For this reason, the solution generally contains a scavenger of OH" radicals. The preferred choice is for solutes whose oxidation by OH" yields radicals which are unable to oxidize the metal ions, but which do have strong reducing properties, for example the radicals of secondary alcohols or of formate anion. The H" radicals are also scavenged by these molecules. 

Anti-inflammatory, anti-mutagenic, and anti-carcinogenic effects Rosemary Antioxidant effect possibly by scavenging of OH radical, singlet oxygen, and peroxynitrite... 

Henglein A, Kormann C (1985) Scavenging of OH radicals produced in the sraiolysis of water. Int J Radiat Biol 48(2) 251-258... 

Fignre 9 illustrates such an in vitro testing of the scavenging efficiency of acetylsalicylic acid/aspirin. As evident, this drag - based on its activity under aerobic conditions within the system HA-ascoibate-Ctf -NaOCl - can be classified as a potent scavenger of OH radicals [48]. 

The hydrated electrons, H atoms, and hydrogen can act as reducing agents. The OH radicals may oxidize metal atoms and ions in intermediate oxidatimi states. To increase the efficiency of the reduction processes, it is conunon to use scavengers of OH radicals (e.g., aliphatic alcohols) ... 

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