In this study, sulfated low molecular-weight Tremella fuciformis polysaccharides (SLTP) with different sulfate contents were synthesized and their antioxidant activities, including superoxide anion radical, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical and hydroxyl radical scavenging activities were investigated. The results indicated that, compared to natural Tremella fuciformis polysaccharide...

Sulfate-reducing bacteria (SRB) are traditionally considered as strict anaerobic microorganisms. But there are a lot of data up to date about survival and metabolic activity of SRB in biotopes periodically exposed to oxygen. The main factor of O2 toxicity is the action of products of oxygen incomplete reduction, so called the reactive oxygen species (superoxide anion radical, hydrogen peroxide ...

In most radicals the singly occupied molecular orbital (SOMO) is the highest-energy occupied molecular orbital (HOMO); however, in a small number of reported compounds this is not the case. In the present work we expand significantly the scope of this phenomenon, known as SOMO-HOMO energy-level conversion, by showing that it occurs in virtually any distonic radical anion that contains a suffici...

Kinetics of radical oxidation of 4-mercapto-2-nitrobenzoic acid was investigated in the presence of hydrogen peroxide and iron(II) sulfate, i.e. SL hydroxyl radicals generating system. Initial velocities of radical reaction were established by numerization of the course of kinetic dependences. The value of initial reaction velocity was used as a criterion for evaluation of efficacy of ethylened...

The metabolism of arbidol in humans was studied using liquid chromatography-electrospray ionization (ESI) ion trap mass spectrometry (ITMS) after an oral dose of 300-mg arbidol. A total of 17 metabolites were identified including the glucuronide arbidol and the glucuronide sulfinylarbidol as the major metabolites. Arbidol and its metabolites have some common fragmentation patterns as a result o...

It has long been known that in acid solution phenazine and related compounds, including N-alkylated derivatives, are oxidized and reduced in distinct l-electron steps, thereby passing through a semiquinoid intermediate (l-4). These semiquinoid forms are stable in acid and have a characteristic green color which readily distinguishes them from the fully oxidized or fully reduced compounds. N-Met...

The free radical scavenging and/or generating activity of dopamine-4-O-sulfate was examined and compared with that of dopamine. In humans, dopamine mostly exists in two isomeric forms of sulfate ester conjugates as metabolites; i.e., dopamine-3-O-sulfate and dopamine-4-O-sulfate in the circulation. Dopamine is generally believed to be oxidized by molecular oxygen or another reactive oxygen spec...

Indoxyl sulfate is a protein metabolite that is concentrated in the serum of patients with chronic renal insufficiency. It also is a uremic toxin that has been implicated in the progression of chronic renal disease in rodent models. We have shown previously that mesangial cell redox status is related to activation of mitogen-activated protein kinases and cell proliferation, which are factors re...

Near-UV photocatalytic disinfection was accomplished in aqueous titanium dioxide suspensions. A level of inactivation of phage MS2 of 90% increased to 99.9% after 2 muM ferrous sulfate was added. Hydroxyl radical oxidation, with Fenton reaction enhancement, is suspected to be primarily responsible for the viral degradation observed.