Relative metabolism of quinones to semiquinone radicals in xanthine oxidase system

✍ Scribed by David C. Lewis; Takayuki Shibamoto

• Book ID: 102293952
• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 400 KB
• Volume: 9
• Category: Article
• ISSN: 0260-437X
• DOI: 10.1002/jat.2550090502

✦ Synopsis

Rates of enzymatic single-electron reduction of some myotoxic quinones to semiquinone metabolites in an in vifro xanthine oxidase/hypoxanthine/catalase system varied widely. Naphthoquinones, especially juglone, were found to undergo rapid single-electron reduction. Benzoquinones and benzoquinoneimines, as well as phenanthrene-9,10-quinone, benzo[a]pyrene-3,6-quinone, and diethylstilbestrolquinone, were also actively reduced. The anthraquinones danthron, doxorubicin and emodin were poorly metabolized in this system. N-Acetylcysteine inhibited quinone-stimulated cytochrome C reduction at high concentrations. The results of this study are discussed with respect to cytotoxicity and mutagenicity of selected quinones.