The Roles of Hydroxyl Radical, Superoxide Anion Radical, and Hydrogen Peroxide in the Oxidation of Arsenite by Ultrasonic Irradiation

Author(s):  
Tielian Xu ◽  
Yong Cai ◽  
Stephen P. Mezyk ◽  
Kevin E. O'Shea
Marine Drugs ◽  
2018 ◽  
Vol 16 (10) ◽  
pp. 394 ◽  
Author(s):  
Long-Yan Li ◽  
Yu-Qin Zhao ◽  
Yu He ◽  
Chang-Feng Chi ◽  
Bin Wang

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.


2013 ◽  
Vol 807-809 ◽  
pp. 1984-1987 ◽  
Author(s):  
Qin Li ◽  
Chi Zhang

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.


1991 ◽  
Vol 261 (2) ◽  
pp. H335-H342 ◽  
Author(s):  
C. W. Leffler ◽  
R. Mirro ◽  
C. Thompson ◽  
M. Shibata ◽  
W. M. Armstead ◽  
...  

In newborn pigs, vasodilation in response to hypercapnia is dependent on prostaglandin (PG) H synthase. We investigated the contribution of activated oxygen by-products to hypercapnia-induced PGH synthase-dependent dilation of pial arteries and arterioles in anesthetized newborn pigs. Activated oxygen species were generated on the cerebral surface using xanthine oxidase and hypoxanthine. Catalase, H2O2, and iron or N-(2-mercaptopropionyl)-glycine (MPG) were used to separate effects of superoxide anion and hydroxyl radical. All the activated oxygen species tested caused vasodilation of both arteries and arterioles. Vasodilation to all activated oxygen species was largely reversible with only the hydroxyl radical encouraging combination of xanthine oxidase, hypoxanthine, H2O2, and FeCl3, causing significant dilation 20 min after removal of treatment. Cotreatment with MPG blocked this residual dilation. Neither pretreatment with the extracellular superoxide anion radical scavenger, superoxide dismutase (SOD), the intracellular superoxide anion radical scavenger, Tiron, the H2O2 scavenger, catalase, nor hydroxyl radical scavengers, dimethyl sulfoxide (DMSO) and MPG, altered vasodilation of pial arteries or arterioles in response to hypercapnia. Furthermore, the increase in cerebral prostanoid synthesis in response to hypercapnia was not affected by pretreatment with SOD, Tiron, catalase, DMSO, or MPG. We conclude that the progressively reduced forms of oxygen that would be produced during PGH synthase metabolism of arachidonic acid can dilate pial arteries and arterioles of newborn pigs. However, these activated oxygen species are not responsible for the vasodilation to hypercapnia in the newborn pig, suggesting that eicosanoids cause the dilation.


2003 ◽  
Vol 9 (2) ◽  
pp. 123-126 ◽  
Author(s):  
T. Nagai

Enzymatic hydrolysates were prepared from lees produced during sake making using fugu muscle and fin. The antioxidant properties of these hydrolysates were measured using four different methods: autoxidation test, superoxide anion radical, DPPH radical and hydroxyl radical scavenging test. The yields of enzymatic hydrolysates were around 8.0% and their protein average content 0.66 mg/mg. The lees had remarkable antioxidant properties and high superoxide anion radical and hydroxyl radical scavenging abilities in comparison with those of ascorbic acid and α-tocopherol. According to the former results, lees produced during sake making could be used as a protein source with antioxidant properties for different applications in food processing, and its use could contribute to reduce industrial wastes.


2013 ◽  
Vol 864-867 ◽  
pp. 531-535
Author(s):  
Ying Chang Li ◽  
Xiao Zhang ◽  
Jian Rong Li

Polyphenols from Porphyra are important biological active substances. The effects of temperature, times, ethanol concentration and liquid to solid ratio were studied for the extraction yield of polyphenols from Porphyra through a single-factor exploration.Then, through an orthogonal experiment, it was investigated to get the best extraction conditions. The content of polyphenols was determined by Folin-Ciocalteu method. Scavenging ability to oxygen free radicals was also assessed. The results show that extraction temperature is 75°C, the extraction time is 2.5 h, ethanol concentration is 70% and the ratio of liquid to solid is 25:1(mL/g).The proportion of the extraction of the polyphenols from Porphyra under these industrial process conditions is 6.263mg/g. Polyphenols from Porphyra have strong scavenging hydroxyl radical and superoxide anion radical. IC50 of polyphenols from Porphyra on hydroxyl radical and superoxide anion radical is 0.405 mg/mL, 0.539mg/mL, respectively.


2001 ◽  
Vol 47 (3) ◽  
pp. 240-247 ◽  
Author(s):  
Tomofumi Okuno ◽  
Hitoshi Kawai ◽  
Tatsuya Hasegawa ◽  
Hitoshi Ueno ◽  
Katsuhiko Nakamuro

2011 ◽  
Vol 183-185 ◽  
pp. 863-867 ◽  
Author(s):  
Chun Wu ◽  
Xin Ping Zheng ◽  
Lin Lin Chen

Dihydromyricetin-zinc(II) complex was synthesized. The scavenging activity of DPPH radical, hydroxyl radical, superoxide anion radical and alkane radical by dihydromyricetin-zinc(II) complex were determine, moreover compared with Vc. The results showed that dihydromyricetin-zinc(II) complex possessed strong scavenging activities on DPPH•, hydroxyl radical, superoxide anion radical and alkane radical with correspounding maximum scavenging rate 74%, 70% , 65% and 50% at the concentration from 0.1 mmol/L to 0.5 mmol/L, respectively, which were higher than Vc. These results suggested that dihydromyricetin-zinc(II) complex would be an effective free radical scavenger.


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