Laser Photolysis of Iron(III) Tetraphenylporphyrin in Methanol. A Kinetic Study on the Formation of the Superoxide Anion Radical from the Dioxygen Adduct of Iron(II) Tetraphenylporphyrin

1998 ◽  
Vol 120 (27) ◽  
pp. 6820-6821 ◽  
Author(s):  
Mikio Hoshino ◽  
Tomoya Baba
Keyword(s):  
Kinetic Study ◽  
Superoxide Anion ◽  
Anion Radical ◽  
Laser Photolysis ◽  
Superoxide Anion Radical

Superoxide Anion Radical: Generation and Detection in Cellular and Non-Cellular Systems

2015 ◽  
Vol 22 (37) ◽  
pp. 4234-4256 ◽  
Author(s):  
Renan Chiste ◽  
Marisa Freitas ◽  
Adriana Mercadante ◽  
Eduarda Fernandes
Keyword(s):  
Superoxide Anion ◽  
Anion Radical ◽  
Cellular Systems ◽  
Superoxide Anion Radical ◽  
Radical Generation

scholarly journals Effect of extraction conditions of paprika oleoresins on their free radical scavenging and anticancer activity

2014 ◽  
Vol 12 (3) ◽  
pp. 377-385 ◽  
Author(s):  
Vesna Šaponjac ◽  
Dragana Četojević-Simin ◽  
Gordana Ćetković ◽  
Jasna Čanadanović-Brunet ◽  
Sonja Djilas ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Cell Line ◽  
Antiproliferative Activity ◽  
Superoxide Anion ◽  
Anion Radical ◽  
Radical Scavenging ◽  
Superoxide Anion Radical ◽  
Food Ingredients ◽  
Supercritical Carbon

AbstractGround spice paprika was extracted with hexane, by conventional Soxhlet procedure (SX oleoresin), and with supercritical carbon dioxide at three different pressures — 20, 30 and 40 MPa (SF20, SF30 and SF40 oleoresins). The effect of extraction method and conditions on the colour intesity of paprika oleoresins, content of α-tocopherol, as well as antioxidant and antiproliferative activity was examined. Hexane showed highest selectivity for paprika pigments (886.02 ASTA), while α-tocopherol showed highest solubility (3846.9 mg kg−1) in supercritical carbon dioxide at 20 MPa. All paprika oleoresins exhibited good superoxide anion radical scavenging activity SF30 being the best superoxide anion radical scavenger. Cell growth activity was evaluated in vitro in human cell lines:cervix epitheloid carcinoma (HeLa), breast adenocarcinoma (MCF7) and colon adenocarcinoma (HT-29). The highest antiproliferative activity was exhibited by SX in MCF7 cell line (IC50=14.28 mg mL−1). Extract SF40 produced significant and selective antiproliferative action towards HeLa cell line. These results suggest that paprika oleoresins, due to high antiradical and tumor cell-inhibiting activity, can be regarded as functional food ingredients.

Scavenging of superoxide anion radical by chaparral

1999 ◽  
pp. 157-161
Author(s):  
Lun-Yi Zang ◽  
Greg Cosma ◽  
Henry Gardner ◽  
Kenneth Starks ◽  
Xianglin Shi ◽  
...  
Keyword(s):  
Superoxide Anion ◽  
Anion Radical ◽  
Superoxide Anion Radical

scholarly journals Physicochemical and Antioxidant Properties of Acid- and Pepsin-Soluble Collagens from the Scales of Miiuy Croaker (Miichthys Miiuy)

Marine Drugs ◽  
2018 ◽  
Vol 16 (10) ◽  
pp. 394 ◽  
Author(s):  
Long-Yan Li ◽  
Yu-Qin Zhao ◽  
Yu He ◽  
Chang-Feng Chi ◽  
Bin Wang
Keyword(s):  
Amino Acid ◽  
Hydroxyl Radical ◽  
Superoxide Anion ◽  
Anion Radical ◽  
Antioxidant Properties ◽  
Superoxide Anion Radical ◽  
Type I ◽  
Dpph Radical ◽  
Soluble Collagen ◽  
Miichthys Miiuy

In this report, acid-soluble collagen (ASC-MC) and pepsin-soluble collagen (PSC-MC) were extracted from the scales of miiuy croaker (Miichthys miiuy) with yields of 0.64 ± 0.07% and 3.87 ± 0.15% of dry weight basis, respectively. ASC-MC and PSC-MC had glycine as the major amino acid with the contents of 341.8 ± 4.2 and 344.5 ± 3.2 residues/1000 residues, respectively. ASC-MC and PSC-MC had lower denaturation temperatures (32.2 °C and 29.0 °C for ASC-MC and PSC-MC, respectively) compared to mammalian collagen due to their low imino acid content (197.6 and 195.2 residues/1000 residues for ASC-MC and PSC-MC, respectively). ASC-MC and PSC-MC were mainly composed of type I collagen on the literatures and results of amino acid composition, SDS-PAGE pattern, ultraviolet (UV) and Fourier-transform infrared spectroscopy (FTIR) spectra. The maximum solubility of ASC-MC and PSC-MC was appeared at pH 1–3 and a sharp decrease in solubility was observed when the NaCl concentration was above 2%. Zeta potential studies indicated that ASC-MC and PSC-MC exhibited a net zero charge at pH 6.66 and 6.81, respectively. Furthermore, the scavenging capabilities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, superoxide anion radical and 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical of ASC-MC and PSC-MC were positively correlated with their tested concentration ranged from 0 to 5 mg/mL and PSC-MC showed significantly higher activity than that of ASC-MC at most tested concentrations (p < 0.05). In addition, the scavenging capability of PSC-MC on hydroxyl radical and superoxide anion radical was higher than those of DPPH radical and ABTS radical, which suggested that ASC-SC and PSC-SC might be served as hydroxyl radical and superoxide anion radical scavenger in cosmeceutical products for protecting skins from photoaging and ultraviolet damage.

scholarly journals Real-time monitoring of superoxide anion radical generation in response to wounding: electrochemical study

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3050 ◽  
Author(s):  
Ankush Prasad ◽  
Aditya Kumar ◽  
Ryo Matsuoka ◽  
Akemi Takahashi ◽  
Ryo Fujii ◽  
...  
Keyword(s):  
Real Time ◽  
Superoxide Anion ◽  
Anion Radical ◽  
Spinacia Oleracea ◽  
Superoxide Anion Radical ◽  
Stress Factors ◽  
Iron Porphyrin ◽  
Real Time Monitoring ◽  
Kinetic Measurements ◽  
Oxidation Current

Background The growth and development of plants is deleteriously affected by various biotic and abiotic stress factors. Wounding in plants is caused by exposure to environmental stress, mechanical stress, and via herbivory. Typically, oxidative burst in response to wounding is associated with the formation of reactive oxygen species, such as the superoxide anion radical (O2•−), hydrogen peroxide (H2O2) and singlet oxygen; however, few experimental studies have provided direct evidence of their detection in plants. Detection of O2•− formation in plant tissues have been performed using various techniques including electron paramagnetic resonance spin-trap spectroscopy, epinephrine-adrenochrome acceptor methods, staining with dyes such as tetrazolium dye and nitro blue tetrazolium (NBT); however, kinetic measurements have not been performed. In the current study, we provide evidence of O2•− generation and its kinetics in the leaves of spinach (Spinacia oleracea) subjected to wounding. Methods Real-time monitoring of O2•− generation was performed using catalytic amperometry. Changes in oxidation current for O2•− was monitored using polymeric iron-porphyrin-based modified carbon electrodes (φ = 1 mm) as working electrode with Ag/AgCl as the reference electrode. Result The results obtained show continuous generation of O2•− for minutes after wounding, followed by a decline. The exogenous addition of superoxide dismutase, which is known to dismutate O2•− to H2O2, significantly suppressed the oxidation current. Conclusion Catalytic amperometric measurements were performed using polymeric iron-porphyrin based modified carbon electrode. We claim it to be a useful tool and a direct method for real-time monitoring and precise detection of O2•− in biological samples, with the potential for wide application in plant research for specific and sensitive detection of O2•−.

A Study of Antioxidant Activity about Seleno-Polysaccharide of Cordyceps militaris from Different Areas of China

2013 ◽  
Vol 807-809 ◽  
pp. 1984-1987 ◽  
Author(s):  
Qin Li ◽  
Chi Zhang
Keyword(s):  
Antioxidant Activity ◽  
Hydroxyl Radical ◽  
Superoxide Anion ◽  
Anion Radical ◽  
Reducing Power ◽  
Cordyceps Militaris ◽  
Superoxide Anion Radical ◽  
Scavenging Capacity ◽  
Research Objects ◽  
Total Selenium

In this article,Cordyceps militaris,that from Hubei and Yunnan,were used as the research objects, to extract seleno-polysaccharide ,then the antioxidant activity of seleno-polysaccharide were determined by reducing power,the scavenging capacity on superoxide anion radical and hydroxyl radical.The results indicated that,the content of selenium in Hubei and Yunnan Cordyceps militaris samples were 210.0μg/g and 57.5μg/g,respectively;the share of Se-polysaccharide in total selenium were 11.086% and 26.713%,respectively,lower degree to turn the selenium organic in Hubei Cordyceps militaris.The reducing power of seleno-polysaccharide from Hubei and Yunnan Cordyceps militaris were 0.0253,0.0297,respectively;two kinds of Cordyceps militaris have certain ability to remove superoxide anion radical and different between them,the seleno-polysaccharide of Yunnan Cordyceps militaris has a better effect to remove superoxide anion radical under different sample amount.About hydroxyl radical,there were no ability to remove it.

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