Complex I (NADH:ubiquinone oxidoreductase) is responsible for most of the mitochondrial H2O2 release, both during the oxidation of NAD-linked substrates and during succinate oxidation. The much faster succinate-dependent H2O2 production is ascribed to Complex I, being rotenone-sensitive. In the present paper, we report high-affinity succinate-supported H2O2 generation in the absence as well as ...

Exposure of either gametes or embryos to conditions and/or factors that generate oxidative stress has been associated with impaired early embryogenesis. The effects of reactive oxygen species (ROS) on mouse preimplantation development, depending of the ROS-concentration and time of exposition, were studied. Two-cell embryos were incubated with 5, 10, 25 and 50 microM of hydrogen peroxide (H2O2)...

Each of 11 tumors tested produced a factor that markedly suppressed the ability of macrophages to release H2O2 or O.2- in response to phorbol myristate acetate or zymosan. Four of seven normal cell types produced a similar activity, which was 3.5-7 times lower in titer than that in tumor cell-conditioned medium (TCM), and which was much more rapidly reversible in its effects. TCM caused 50% inh...

The E. coli inactivation using hydrogen peroxide (H2O2) and cobalt ferrite granulated catalyst was investigated in a fixed-bed flow reactor. CoFe2O4 synthesized by the co-precipitation method, granulated, annealed at 1150°C. X-ray diffraction analysis used to identify crystal structure of catalyst. demonstrates good catalytic activity for bacteria presence H2O2. An increase concentration increa...

Hydrogen peroxide (H2O2) is present ubiquitously in marine surface waters where it is a reactive intermediate in the cycling of many trace elements. Photochemical processes are considered the dominant natural H2O2 source, yet cannot explain nanomolar H2O2 concentrations below the photic zone. Here, we determined the concentration of H2O2 in full depth profiles across three ocean basins (Mediter...

Mitochondria fulfill a number of biological functions which inherently depend on ATP and O2(-•)/H2O2 production. Both ATP and O2(-•)/H2O2 are generated by electron transfer reactions. ATP is the product of oxidative phosphorylation whereas O2(-•) is generated by singlet electron reduction of di-oxygen (O2). O2(-•) is then rapidly dismutated by superoxide dismutase (SOD) producing H2O2. O2(-•)/H...

BACKGROUND Hydrogen peroxide (H2O2) and reactive oxygen species are implicated in inflammation, ischemia-reperfusion injury, and atherosclerosis. The role of ion channels has not been previously explored. METHODS AND RESULTS K+ currents and membrane potential were recorded in endothelial cells by voltage- and current-clamp techniques. H2O2 elicited both hyperpolarization and depolarization of...

[1] We report new century-scale ice core records of hydrogen peroxide (H2O2), a major atmospheric oxidant, from 23 locations across the West Antarctic Ice Sheet (WAIS) and use the spatial variability of (multi-) annual mean H2O2 concentrations in snow and firn to investigate the sensitivity of ice core H2O2 preservation to mean annual temperature and accumulation rate. In agreement with the ice...

objective: ferula szowitsiana has been widely used for medicinal purposes around the world. the anti-oxidant effect of f.szowitsiana had been proved. the current study aims to determine the protective effects of galbanic acid, a sesquiterpene coumarin from f. szowitsiana, against hydrogen peroxide (h2o2) - induced oxidative dna damage in human lymphocytes. materials and methods: human lymphocyt...

This paper reports on the response of a fiber-optic sensing probe to small concentrations of hydrogen peroxide (H2O2) vapor at room temperature. H2O2 has extensive applications in industrial and medical environments. Conversely, H2O2 can be a health hazard by itself. For example, H2O2 induces cellular damage in human cells and its presence can be used to diagnose illnesses such as asthma and hu...