Active oxygen species inhibition

Inhibition of XO by uric acid apparently occurs under in vivo conditions. Thus, it has been shown [16] that physiological levels of uric acid inhibited XO activity in human plasma. Activity and superoxide production by XO are also inhibited by many metal ions such as Ag+, Hg2+, Zn2+,Cu2+, Cr6+, etc. [17] or hyperoxia and active oxygen species [18]. 

A possible but not yet fully proven carcinogenity of hardmetal dust could result from a synergism between the activated oxygen species (genotoxicity—damage to DNA) and the already proven repair inhibition by Co " ". 

Mishra NP, Mishra RK and Singhal GS (1993) Involvement of active oxygen species in photoinhibition of Photosystem II protection of photosynthetic efficiency and inhibition of lipid peroxidation by superoxide dismutase and catalase. J Photo-chem Photobiol B Biol 19 19-24 Miyake C and Asada K (1992) Thylakoid-bound ascorbate peroxidase in spinach chloroplasts and photoreduction of its primary oxidation product monodehydroascorbate radicals in thylakoids. Plant Cell Physiol 33 541-553 Miyake C and Asada K (1994) Ferredoxin-dependent photoreduction of the monodehydroascorbate radical in spinach thylakoids. Plant Cell Physiol 35 539-549 Miyake C, Schreiber U, Hermann H, Sano S and Asada K (1996) Monodehydroascorbate radical reductase-dependent photoreduction of oxygen in chloroplast thylakoids. Plant Cell Physiol 37 s284... 

Virus inactivation by hypericin seems to involve inhibition of various stages of virus replication depending on the integrity of the viral envelope. Photoactivation of hypericin leads to the formation of active oxygen species that likely react with viral components making them unable to assembly into complete virus particles. 

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