The influence of low-molecular-weight organic acids (LMWOAs), such as malonic acid, ethylenediaminetetraacetic acid, and oxalic acid, on the Fenton degradation of organic pollutants was examined under visible irradiation (lambda > 450 nm). The Fenton degradation of malachite green in the dark was completely blocked in the presence of LMWOAs. It was found that either visible light irradiation or...

Exogenous ochronosis is an infrequent dermatosis characterized as a dark blue hyperpigmentation localized where the causing agent was applied. It may be caused by the use of systemic medication such as antimalarials and by the use of topic substances such as phenol, resorcinol, benzene, or hydroquinone, which is a fenolic compound with depigmentation action, largely used in the treatment of mel...

The reactions of glutathione (GSH) with polychlorinated biphenyl (PCB) quinones having different degrees of chlorination on the quinone ring were examined. EPR spectroscopy and MS revealed 2 types of reactions yielding different products: (i) a nonenzymatic, nucleophilic displacement of chlorine on the quinone ring yielding a glutathiylated conjugated quinone and (ii) Michael addition of GSH to...

At present, there is an ongoing search for approaches toward the storage of energy from intermittent renewable sources like wind and solar. Flow batteries have gained attention due to their potential viability for inexpensive storage of large amounts of energy. While the quinone/hydroquinone redox couple is a widely studied redox pair, its application in energy storage has not been widely explo...

A mixture of two benzene metabolites, hydroquinone and catechol, produces a striking synergistic genotoxic response in cultured human lymphocytes. This was demonstrated using an anti-kinetochore antibody modification of the micronucleus assay. Treatment with hydroquinone alone or in combination with phenol produced a 3-fold increase in micronucleated cells over background. Treatment with catech...

Hydroquinone, a metabolite of benzene, and acetaldehyde, a metabolite of ethanol, induce sister chromatid exchanges (SCEs) at relatively high concentrations. Because both compounds are reported to form glutathione conjugates, experiments were carried out to see if there was a synergistic effect when lower concentrations of both chemicals were added to human lymphocyte cultures. Hydroquinone (40...

It has previously been proposed that 4-methylphenol (p-cresol) is metabolically activated by oxidation of the methyl group to form a reactive quinone methide. In the present study a new metabolism pathway is elucidated in human liver microsomes. Oxidation of the aromatic ring leads to formation of 4-methyl-ortho-hydroquinone, which is further oxidized to a reactive intermediate, 4-methyl-ortho-...

Arbutin (hydroquinone β-D-glucoside) is a compound of plant origin possessing valuable therapeutic (urinary tract disinfection) and cosmetic (skin whitening) properties, which can be obtained from in vitro cultures of plants belonging to different taxa via biotransformation of exogenously supplemented hydroquinone. Agitating cultures of Aronia melanocarpa were maintained on the Murashige and Sk...

New kinds of hydroquinone derivatives were synthesized and along with a azo dye applied as additives in the iodide/iodine redox electrolyte for dye-sensitized solar cells and their effect on the short-circuit photocurrent of dye sensitized solar cells was investigated. Addition of 0.05 M a hydroquinone derivative in the electrolyte comprising 0.5 M 1-methyl-3-propylimidazolium iodide (MPII) and...