Typical oxidation of polyphenols is best depicted by the oxidation of a diphenolic compound (catechol) into the corresponding quinone (Equation (10)) and of enediol
(ascorbic acid) into vicinal diketone (Equation (11)):
As shown in Figure 15, Amadori product 80 may be converted via enediol
81 to dicarbonyl 82, with coformation of [H.sub.2][O.sub.2].
Chronic exposure to high glucose levels increases the oxidation of glucose itself, which produces enediol
and dihydroxy compounds as well as a significant amount of ROS .
phosphate, an intermediate of triosophosphate isomerase reaction, may escape from the active site of the enzyme and be rapidly decomposed to MGO and inorganic phosphate.
This leads to formation of an enediol
or enediolate stabilized by Lys13 .
The annealead [Fe.sub.2][O.sub.3]-ITO slides photocurrents were measured in a three-electrode photoelectrochemical cell under irradiation with a Xenon lamp before and after modification with enediol
ligands baring different pendant chemical groups.
It has been reported in the literature that in alkaline medium sugar will form enediol
with the hydroxyl group and also that the rate of enolization is the same as the rate of oxidation  However, in the present study, the double reciprocal plots of the pseudo-first-order rate constants against the sugar concentrations were linear (fig.
El mecanismo basico consiste en la transformacion del grupo carbonilo libre (oxidable por oxigeno y otros oxidantes) en enediol
por accion del calor y la solucion alcalina [2,3,].
The absorbance spectra of the TiO2/ITO slides are measured before and after deposition, annealing and surface modification with enediol
The FC method suffers from a number of interfering substances particularly sugars, aromatic amines, sulfur dioxide, ascorbic acid and other enediols
and reductones, organic acids, and Fe (II), and correction for interfering substances should be made.
Regarding influences that involve sugar chemistry, oxygenated free radicals which resulted in early glycation stages have been proven to be contributors to glycoxidative damage: glycolaldehyde that results in the initial stages of nonenzymatic glycosylation is noncyclizable and may undergo tautomerization, yielding enediols
that are easily subject to autooxidation.