Reference

Inhibition of xanthine oxidase by cytokinins and related substances

Inhibition of xanthine oxidase by cytokinins and related substances. Sheu, Shiow-Yunn; Lin, Yu-Chan; Chiang, Hsuch-Ching (Sch. Pharm., Taipei Med. Coll., Taipei 105, Taiwan). Anticancer Research, 16(6B), 3571-3576 (English) 1996 Anticancer Research. CODEN: ANTRD4. ISSN: 0250-7005. DOCUMENT TYPE: Journal CA Section: 7 (Enzymes) Fourteen cytokinins were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase catalyzes the oxidn. of hypoxanthine to xanthine and of xanthine to uric acid which has lmax of 295 nm, forming the basis for a spectrophotometric assay of the activity of xanthine oxidase. The results showed that adenine-HCl, N6-(2-isopentenyl)-adenine, purine and DL-dihydrozeatin displayed very potent activities (IC50=1.92, 10.99, 60.98 and 86,36 mM resp.). Their apparent inhibition consts. (Ki) were 2.20, 17.99, 13.59 and 115.In this experiment, several chemicals are used like 2365-40-4 and 2922-28-3 62 mM, and induced competitive, uncompetitive, competitive and non-competitive type inhibitions resp. with respect to the substrate xanthine. .