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The Chemistry of Hazardous Materials
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
Mixtures of the oxides and peroxides are possible and common for sodium, and mixtures of oxides, peroxides, and superoxides are possible and common for potassium, when they are burned in air. A superoxide is more properly called a hyperoxide and is a highly reactive oxidizing agent.
Aegle marmelos
Published in Cristobal N. Aguilar, Suresh C. Ameta, A. K. Haghi, Green Chemistry and Biodiversity, 2019
Hema Joshi, Rajeev Singh, Anamika Singh
Studies have reported that the reducing power of bael extract was high and it further increased with an increase in the concentration of the extract. Superoxide anion is harmful reactive oxygen species that causes severe damage to the cells. It was found that bael extract had a great ability to scavenge superoxide anion and protect the cells against damage. In simple words, bael fruit pulp is a great source of antioxidant and it can successfully combat oxidative stress.
Carbonaceous and Polysaccharide-Based Nanomaterials: Synthesis and Their Importance in Environmental Applications
Published in Surender Kumar Sharma, Nanohybrids in Environmental & Biomedical Applications, 2019
Jaise Mariya George, Ragam N. Priyanka, Beena Mathew
Photocatalysts based on graphene reportedly deactivated bacteria due to their capacity to reduce oxygen to hydrogen dioxide. However, further improvements in the study are not available. CNTs are promising as photocatalysts since they can generate electron-hole pair upon exposure to light owing to the presence of semiconductor nature and low energy gap between the valence and conduction bands. They are mesoporous in nature and have high mechanical strength and suitable chemical, electrical and thermal features to support great applications. In addition, the sp2 carbon network allows the longtime travel of electrons and thus reduces electron–hole recombination. The free electrons and holes are the particles which can generate ROS or radicals. The generated hydroxide and superoxide radicals are highly efficient oxidizing agents which can degrade the organic pollutants present in water.
Structures, fluorescence, and superoxide radical scavenging activities of two cd–Ln (Ln = Gd, Er) coordination polymers with an open-chain ether Schiff base and isonicotinate
Published in Journal of Coordination Chemistry, 2022
Jianping Dong, Ruixue Li, Fugang Sun, Yuxuan Jiang, Huilu Wu
Superoxide is one of the by-products of normal metabolism. In living systems, it will attack key biological molecules, causing cell damage or death, inflammatory diseases, and many age-related diseases [61–63]. Therefore, the best choice is to clear it as much as possible. It is known that some Schiff bases and their complexes show wonderful activity to clear superoxide radicals [64–66]. Superoxide radical scavenging activities in vitro of H2L, 1 and 2 are displayed in Figure 5; they all evinced distinct clearing of O2−·. The superoxide radical scavenging activities in vitro (reflected by IC50) of H2L, 1 and 2, a series of complexes based on open-chain ether Schiff base ligands [8, 45, 46, 67–72], and Vitamin C (Vc) reported by others [73], are summarized in Table 5. The following conclusions were summarized by comparison: (i) The superoxide radical scavenging activities of the complexes were higher than that of the corresponding free ligands; (ii) The order of superoxide radical scavenging activities of the complexes: lanthanide complexes < d–f trinuclear complexes < d–f coordination polymers < d–f decanuclear complexes; (iii) Complexes with the same structure have approximately the same scavenging activities of superoxide radicals. These conclusions will provide help for follow-up research.
Behavioral and Oxidative Stress Responses of Earthworm, Nsukkadrilus mbae (Segun 1976), Exposed to Lead and Cadmium: A Preliminary Investigation
Published in Soil and Sediment Contamination: An International Journal, 2021
Ifeanyi O. Aguzie, Kenechukwu D. Enekwe, Ijeoma J. Emekekwue, Chinweike N. Asogwa, Grace C. Onyishi, Ndubuisi S. Oluah, Felicia N. Ekeh, Christopher D. Nwani
Superoxide dismutase (SOD) increased on short-term in N. mbae at the 500 µg/g Pb and 10 µg/g Cd, this was significant statistically for Pb. The effect on SOD waned on d-30. SOD is an enzyme that alternately catalyses the dismutation of superoxide radical into either ordinary molecular oxygen or hydrogen peroxide (Fukai and Ushio-Fukai 2011; Wang et al. 2018). Superoxide is produced as a by-product of oxygen metabolism and, if not regulated, causes many types of cell damage (Bannister, Bannister, and Rotilio 1987; Forrester et al. 2018). Increased SOD activity were among the findings for other earthworm species following exposure to toxicants: e.g. Eudrilus eugeniae (Tiwari, Singh, and Pandey 2019), Hyperiodrilus africanus (Olujimi et al. 2020) and Eisenia fetida (Liu et al. 2010). Following exposure to toxicant and subsequent generation of free radicals, up-regulation of endogenous enzymatic antioxidants production mechanism is expected leading to increased activities of enzymes such as SOD (He et al. 2017) as observed in our study. Reduction in N. mbae SOD activity on prolonged exposure to the heavy metal, is similar to the observation made by Maity et al. (2018) who noted a decline in SOD activity of Eisenia fatida exposed to Cd-contaminated soil for more than 14 days. Cd exposure is known to inhibit SOD activity on long-term in earthworms (Zhang et al. 2009). A long-term reduction of SOD activity at Cd concentration of 2 and 10 µg/g and Pb concentration of 20 and 500 µg/g occurred in the earthworm N. mbae, in our study.
Resveratrol attenuates hydrogen peroxide-induced oxidative stress in TM3 Leydig cells in vitro
Published in Journal of Environmental Science and Health, Part A, 2020
Hana Greifová, Tomáš Jambor, Katarína Tokárová, Ivana Speváková, Nikola Knížatová, Norbert Lukáč
It is well known, that ROS including superoxide anion and hydrogen peroxide are products of aerobic respiration. During respiration, electrons released from the mitochondrial electron transport chain reduce O2 to form superoxide and superoxide is then converted into H2O2, which in turn may be partially reduced to hydroxyl radical. As an increase of hydrogen peroxide concentration induces oxidative stress associated with increased hydroxyl radical production, we have evaluated the ability of resveratrol to protect Leydig cells from triggering further production of superoxide radical due to the overall oxidative stress state induced by hydrogen peroxide as well as under normal conditions. Our analyses revealed that low doses of resveratrol can reduce the intracellular formation of superoxide radical even under the condition of induced oxidative stress after 24 h of cultivation, which is also evident in terms of viability.