Reactive oxygen species (ROS) play important roles in follicular development and survival. Granulosa cell death is associated with increased ROS, but the mechanism of granulosa cell death induced by ROS is not clear. In order to define the molecular link between ROS and granulosa cell death, COV434, human granulosa tumor cells, were treated with H2O2. Compared to control cells, H2O2 induced gra...

Mushrooms are prone to microbial spoilage and browning during growing and processing. Ultraviolet light (254 nm, UV-C) has been used as an alternative technology to chemical sanitizersfor food products. Hydrogen peroxide (H2O2) is classified as generally recognized as safe for use in foods as a bleaching and antimicrobial agent, and could control the bacterial blotch and browning of mushrooms. ...

Ocean warming has exacerbated the severity of coral diseases, many of which are mediated by pathogenic bacteria. In response to the presence of pathogens various organisms activate an oxidative burst response, involving strong and rapid generation of reactive oxygen species (ROS) that serve both as bactericides and as signals for other defense systems. While many components of the coral immune ...

19 Fe/ascorbate, hydrogen peroxide (H2O2) and hypoxanthine/xanthine oxidase (XOD) are commonly used for 20 inducing oxidative stress on spermatozoa. A comparative study of these agents was carried out on thawed 21 spermatozoa from red deer. First, we tested a high, medium and low concentration of each agent: 100, 10 and 22 1 μM Fe (hydroxil radical generator); 1 mM, 100 and 10 μM H2O2; and 100,...

We demonstrate that the copolymers containing boronic acid and pyrene units can be utilized for the fluorometric sensing of hydrogen peroxide (H2O2) in aqueous solutions. The copolymer exists in a relatively extended conformation in the absence of H2O2, whereas the polymer chain is contracted by the reaction of boronic acid moieties with H2O2 to form phenol groups. This conformational change in...

We have measured the release of H2O2 from granulocytes, monocytes, and macrophages during spreading on ligand-coated culture surfaces. While IgG-coated surfaces stimulate vigorous release of H2O2, neither C3b- nor C3bi-coated surfaces promoted appreciable release of H2O2 despite full ligation of C3b and C3bi receptors. We also measured release of H2O2 from cultured monocytes spreading on surfac...

Hydrogen peroxide (H2O2) is used by phagocytic cells of the innate immune response to kill engulfed bacteria. H2O2 diffuses freely into bacteria, where it can wreak havoc on sensitive biomolecules if it is not rapidly detoxified. Accordingly, bacteria have evolved numerous systems to defend themselves against H2O2, and the importance of these systems to pathogenesis has been substantiated by th...

The active oxygen species hydrogen peroxide (H2O2) was detected cytochemically by its reaction with cerium chloride to produce electron-dense deposits of cerium perhydroxides. In uninoculated lettuce leaves, H2O2 was typically present within the secondary thickened walls of xylem vessels. Inoculation with wild-type cells of Pseudomonas syringae pv phaseolicola caused a rapid hypersensitive reac...

6-Mercaptopurine (6-MP) is a commonly used cytostatic agent, which represents particular hazard for the environment because of its low biodegradability. In order to degrade 6-MP, four processes were applied: Photolysis (UV-C), photocatalysis (UV-C/TiO2), and their combination with H2O2, by adding 3 mM H2O2/L (UV-C/H2O2 UV-C/TiO2/H2O2 processes). Each process was performed variable initial pH (3...