The fluorescent derivatization of tryptophan metabolites (xanthurenic acid, nicotinic acid, picolinic acid, and 3-hydroxyanthranilic acid) by the catalytic activity of horseradish peroxidase (HRP) was investigated in the presence of excess H(2)O(2). Non-fluorescent xanthurenic acid (XA) and nicotinic acid (NA) were converted into a fluorescent compound with maximum excitation and emission wavel...

The oxidation of 3-hydroxyanthranilic acid, an intermediate in the conversion of tryptophan to niacin (l-3), is catalyzed by a liver oxidase (4). The first recognized product, termed Compound I (5), yields quinolinic acid spontaneously or picolinic acid under the influence of a liver carboxylase (6). The intermediate is detectable by its absorption maximum at 360 rnp (4). Wiss and Bettendorf (7...

Metal complexes of divalent Nickel and Cobalt metal ions have been synthesized with picolinic acid hydrazide (PH) , ortho -hydroxy acetophenone picolinoyl hydrazone ( APH) ortho-hydroxy iso-nicotinoyl (AIH) ligands were isolated at both high pH low pH. These characterized by elemental analyses also electronic spectral studies magnetic measurements. Ligands PH AIH act as tridentate, while APH is...

A new metal–organic complex (MOC), Mn(L)2·4H2O is successfully designed and synthesized by 2-(1,2,4-Triazol-1-yl)-4-picolinic acid ligand Mn(NO3)2·4H2O in the mixed solvent of methanol water. The was characterized single-crystal X-ray diffraction, element analysis, Powder diffraction(PXRD). binding constant between DNA 9.3 × 104, indicating that fish sperm can bind well. Viscosity experiments p...

A novel 12-molybdophosphoric acid (HPM)-based complex (H2PI)2(H3O)[PMo12O40] [Mo2O5(H2O)2(PI)2]·11H2O (PI-HPM) was prepared by modification with picolinic acid (HPI) and characterized by the methods of Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG), X-ray powder and single crystal diffraction. The complex retained the classical Keggin structure of bulk HPM, there were som...

Kynurenines are the products of tryptophan metabolism. Among them, kynurenine and kynurenic acid are generally thought to have neuroprotective properties, while 3-hydroxykynurenine, 3-hydroxyanthranilic acid and quinolinic acid are considered neurotoxic. They participate in immunoregulation and inflammation and possess pro- or anti-excitotoxic properties, and their involvement in oxidative stre...