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Updated: Aug 25, 2026

Biochemical Measurement of Neonatal Hypoxia
Published on: August 24, 2011
Characterization of xanthine oxidase inhibition by anacardic acids
1Department of Biochemistry, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikatacho, Okayama 700-8558, Japan. masuokan@md.okayama-u.ac.jp
Abstract:
Anacardic acid, 6[8(Z), 11(Z), 14-pentadecatrienyl]salicylic acid, inhibits generation of superoxide radicals by xanthine oxidase. This inhibition does not follow a hyperbolic inhibition, depends on anacardic acid concentrations, but follows a sigmoidal inhibition. The inhibition was analyzed by using a Hill equation, and slope factor and EC(50) were 4.3+/-0.5 and 53.6+/-5.1 microM, respectively. In addition, anacardic acid inhibited uric acid formation by xanthine oxidase cooperatively. Slope factor and EC(50) were 1.7+/-0.5 and 162+/-10 microM, respectively. The results indicate that anacardic acid binds to allosteric sites near the xanthine-binding domain in xanthine oxidase. Salicylic acid moiety and alkenyl side chain in anacardic acid are associated with the cooperative inhibition and hydrophobic binding, respectively.
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