To assay the in vitro xanthine oxidase and Tyrosinase inhibitory activity of the alkaloid fractions of the leaves of Indigofera spalathoides and to determine its enzyme inhibition mechanism. Xanthine oxidase and Tyrosinase inhibitory activity was assayed spectrophotometrically under aerobic conditions and the degree of enzyme inhibition was determined by measuring the increase in absorbance at ...

The quinimine form of p-aminophenol inhibits the oxygen uptake of tissue suspensions and in very small concentrations inhibits specifically the oxidation of hypoxanthine and xanthine to uric acid by the xanthine oxidase of liver (1). Closely related compounds such as o-aminophenol, p-phenylenediamine, and quinone, although they inhibit to different degrees the oxygen uptake of tissues, have no ...

The HPTLC analysis, antioxidant, and antigout activity of Asparagus racemosus, Withania somnifera, Vitex negundo, Plumbago zeylanica, Butea monosperma and Tephrosia purpurea extracts were investigated. The chemical fingerprinting were carried out by high performance thin layer chromatography (HPTLC), antioxidant activity by ABTS, DPPH, FRAP radical scavenging assays, and antiogout activity by c...

Previous studies from this laboratory (1) have demonstrated the existence of several different types of “xanthine oxidase” in nature. The enzymes in milk and mammalian tissues appear to be quite similar, but can be differentiated by the inhibitor Antabuse, which affects only the tissue enzyme (2). Antabuse can also be used to separate the dehydrogenase and oxidase activities of tissue xanthine ...

Xanthine oxidase activity containing fractions from rat, mouse, rabbit and guinea pig livers were obtained by heat treatment and ammonium sulfate precipitation. Xanthine oxidase activity was observed in rat and mouse liver fractions, while xanthine oxidase activity was absent in rabbit and guinea pig liver fractions. Enzyme kinetic parameters, K m and V max , were determined for the conversion ...

Oxygen metabolites have been implicated in the pathogenesis of various types of acute tissue injury. One biologic source of oxygen metabolites is the reaction catalyzed by the enzyme xanthine oxidase. Because we previously demonstrated that the substrates for xanthine oxidase (hypoxanthine and xanthine) are elevated in the plasma of critically il l patients, we questioned whether the enzyme its...

As the enzyme responsible for uric acid formation, Xanthine oxidase was considered to be a therapeutic target hyperuricemic treatment. This study carried out assess potential of caryophyllene, and its derivates usually present in natural product inhibit oxidase. The molecular docking using Autodock Tool Biovia Discovery Studio conducted visualize interaction reveal structure-activity relationsh...

In 1948 Miller (1) demonstrated that the loss of liver xanthine oxidase activity in the rat greatly exceeded the loss of liver protein during acute inanition. Moreover, xanthine oxidase appeared to be the most labile of the four liver enzymes studied. Westerfeld and Richert (2) observed that increasing the level of protein in the diet tended to bring about an increase in liver xanthine oxidase ...

Previous papers examined lipid peroxidase levels and myeloperoxidase activity as products of oxidative and inflammatory reactions in the tear fluid of patients suffering from dry eye. The aim of the present paper was to investigate whether the enzymes xanthine oxidoreductase/xanthine oxidase known to generate reactive oxygen species contribute to oxidative reactions on the ocular surface. Xanth...