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Superoxide Scavenging Effects of Some Novel Bis-Ligands and Their Solvated Metal Complexes Prepared by the Reaction of Ligands with Aluminum, Copper and Lanthanum Ions  [PDF]
Shigeki Kobayashi,Sachi Kanai
Molecules , 2013, DOI: 10.3390/molecules18066128
Abstract: Novel antioxidants have been synthesized and characterized by their chemical properties as antioxidants with high superoxide scavenging activity. (2 R,3 R)-diphenylethylenediamine is a spacer in antioxidants, and we synthesized targets 11a and 11b by conjugation with o-hydroquinone and p-hydroquinone at the two N-termini, respectively. Superoxide scavenging activities of the plant flavonoid-like 11 a and 11 b were compared with those of known antioxidants, and shown to increase in the following order: curcumin << ascorbic acid < Trolox < ()-epicatechin < 11a < quercetin ≤ 11b?. Compound 11a also formed a solvated 11 a–metal complex with metal ions. The 11a–Cu 2+ complex was shown to have higher superoxide scavenging activity than that of 11a, 11b, Cu 2+, and the 11a–Al 3+ and 11a–La 3+ complexes, whereas the 11a–Al 3+ complex increased rather than decreased superoxide levels. The 11a–Al 3+ complex did not abstract one electron from the SOMO of O 2 ?. since the HOMO and LUMO phases of Al 3+ do not exist in the center of the 11a–Al 3+ complex. However, the SOMO of the 11a–Cu 2+ complex distributed in the center of Cu 2+ may abstract one electron from the SOMO of O 2 ?.. These results suggest that 11 a and 11 b are powerful antioxidants.
Superoxide Scavenging and Tyrosinase Inhibitory Active Compound in Ginger (Zingiber officinale Roscoe)
F. Khanom,H. Kayahara,M. Hirota,K. Tadasa
Pakistan Journal of Biological Sciences , 2003,
Abstract: The superoxide-scavenger and tyrosinase inhibitory active material was extracted by methanol from ginger (Zingiber officinale Roscoe) and was partitioned into hexane, aqueous and ethyl acetate parts. The highly active hexane soluble part was subjected to fractioned by silica gel column chromatography and was obtained in eight fractions. All most all fractions gave a remarkable amount of superoxide-scavenging and tyrosinase inhibitory activities. The highest superoxide-scavenging and tyrosinase activities were found in the fraction five (58.2 and 42.7%, respectively) and its purity was confirmed by thin layer chromatography (TLC). This fraction was amounting as 274.3 mg and characterized by nuclear magnetic resonance (NMR), infrared (IR) and mass spectrometer. The compound was gingerol and its structure was confirmed as 3-decanone, 5-hydroxy-1 (4-hydroxy-3-methoxy phenyl) -3-one on the basis of spectral evidence.
Zinc, copper, magnesium, proteins and superoxide dismutase in acne
Madadi A,Sethi N,Bhandari S
Indian Journal of Dermatology, Venereology and Leprology , 1993,
Abstract: Serum zinc, copper, magnesium, proteins and superoxide dismutase (SOD) were studied in 40 cases of acne. Serum zinc, magnesium and albumin were found to be significantly decreased whereas serum copper and globulin were significantly increased. There were no significant alterations in the serum total proteins and SOD in the above cases.
Mechanism and kinetics for scavenging superoxide anion by progesterone
Junfeng Song,Yong Shao,Wei Guo
Chinese Science Bulletin , 2001, DOI: 10.1007/BF03187004
Abstract: The chemical reaction of progesterone with superoxide anion O 2 . in 0.1 mol/L NaHCO3 medium is studied by polarography. Differing from the indirect inhibition of O 2 . generation by synthesized glucocorticoids in mechanism, the function that progesterone scavenges O 2 . is ascribed to that O 2 . directly oxidizes the C = C double bond conjugated with the carbonyl moiety of progesterone molecule to a free radical, and then is reduced to H2O2. The result obtained in this work gives new evidence for biomedical research. The equation of rate constant of the oxidization reaction is deduced, and the apparent rate constant obtained is 308 L · mol 1 · s 1.
Mechanism and kinetics for scavenging superoxide anion by progesterone

Junfeng Song,Yong Shao,Wei Guo,

科学通报(英文版) , 2001,
Abstract: The chemical reaction of progesterone with superoxide anion O.-2 in 0.1 mol/L NaHCO3 medium is studied by polarography. Differing from the indirect inhibition of O.-2 generation by synthesized glucocorticoids in mechanism, the function that progesterone scavenges O.-2 is ascribed to that O.-2 directly oxidizes the C == C double bond conjugated with the carbonyl moiety of progesterone molecule to a free radical, and then is reduced to H2O2. The result obtained in this work gives new evidence for biomedical research. The equation of rate constant of the oxidization reaction is deduced, and the apparent rate constant obtained is 308 L·mol-1·s-1.
Vasorelaxation and Superoxide Scavenging Activities of Orotic Acid  [PDF]
S. Prachayasittikul,O. Wongsawatkul,A. Worachartcheewan,S. Ruchirawat
International Journal of Pharmacology , 2010,
Abstract: The aim of study is to investigate effects of orotic acid (OA) on phenylephrine-induced contraction of rat thoracic aorta and its antioxidative activity. Results showed that the OA exhibited maximal vasorelaxation in dose-dependent manner with ED50 of 3.16x10-7 M, but the effect was less than those of acetylcholine (ACh)-induced nitric oxide (NO) vasorelaxation. Significant reductions of the vasorelaxations were found in the presence of either NG-nitro-L-arginine methyl ester (L-NAME) or indomethacin (INDO). Synergistic effects were observed in the presence of L-NAME plus INDO that led to loss of vasorelaxation of both the ACh and the OA. In addition, complete loss of the vasorelaxation was manifested under removal of endothelial cells. This implies that the vasorelaxations are mediated by partially endothelium-induced NO and prostacyclin. The OA exhibited antioxidative activity in both DPPH and SOD assays. The significant results reveal novel actions of the OA as vasorelaxants and superoxide scavenger which are benefits as therapeutic uses and health supplements.
Formation of Copper Nickel Bimetallic Nanoalloy Film Using Precursor Inks  [PDF]
Chaitanya G. Mahajan, Amanda Marotta, Bruce E. Kahn, Mark Irving, Surendra Gupta, Richard Hailstone, Scott A. Williams, Denis Cormier
Materials Sciences and Applications (MSA) , 2019, DOI: 10.4236/msa.2019.104026
Abstract: Precursor (Metal-organic decomposition (MOD)) inks are used to fabricate 2D and 3D printed conductive structures directly onto a substrate. By formulating a nanoalloy structure containing multiple metals, the opportunity to modify chemical and physical properties exists. In this paper, a copper-nickel bimetallic nanoalloy film was fabricated by mixing copper and nickel precursor inks and sintering them in vacuum. The individual elemental inks were formulated and characterized using SEM, EDS, and XRD. During thermal processing, elemental copper forms first and is followed by the formation of bimetallic copper-nickel alloy. The encapsulation of the underlying copper by the nickel-rich alloy provides excellent oxidation resistance. No change in film resistance was observed after the film was exposed to an oxygen plasma. Nanoalloy films printed using reactive metallic inks have a variety of important applications involving local control of alloy composition. Examples include facile formation of layered nanostructures, and electrical conductivity with oxidative stability.
Immobilization and direct electrochemistry of copper-containing enzymes on active carbon
Dongmei Sun,Chenxin Cai,Wei Xing,Tianhong Lu
Chinese Science Bulletin , 2004, DOI: 10.1007/BF03183712
Abstract: Two typical and important copper-containing enzymes, laccase (Lac) and tyrosinase (Tyr), have been immobilized on the surface of active carbon with simple adsorption method. The cyclic voltammetric results indicated that the active carbon could promote the direct electron transfer of both Lac and Tyr and a pair of well-defined and nearly symmetric redox peaks appeared on the cyclic voltammograms of Lac or Tyr with the formal potential,E 0’, independent on the scan rate. The further experimental results showed that the immobilized copper-containing oxidase displayed an excellent electrocatalytic activity to the electrochemical reduction of O2. The immobilization method presented here has several advantages, such as simplicity, easy to operation and keeping good activity of enzyme etc., and could be further used to study the direct electrochemistry of other redox proteins and enzymes and fabricate the catalysts for biofuel cell.
Ferrous Ion Chelating, Superoxide Anion Radical Scavenging and Tyrosinase Inhibitory Properties of Pure and Commercial Essential Oils of Anetrhum Graveolens
M Dadashpour,I Rasooli,F Sefidkon,M Bagher Rezaei
Journal of Shahid Sadoughi University of Medical Sciences , 2013,
Abstract: Introduction: Despite slight toxicities of essential oils, they are not under strict control in many countries. Anethum graveolens is widely consumed and its essential oils are at public reach. This study was designed to study essential oils of Anethum graveolens. Methods: The biological properties of pure and commercial essential oils of Anethum graveolens were investigated. In fact, Ferrous ion chelating activity, superoxide anion radical scavenging property, tyrosinase inhibition and total flavonoids of the oils were determined. Results: Chelating activity of 7.8 μg of EDTA was equivalent to 2 μg of the pure oil. The oils had superoxide anion radical scavenging activities which may be related to their total phenol and flavonoid contents. IC50 of ferrous ion chelating, antityrosiase and superoxide anion radical scavenging activities of pure and commercial oils were 1.3, 1.4, 1 and (171.6, 589, 132) μg respectively. Antityrosiase activity of 6.4 μg pure oil was equal to 1000 μg of the commercial oil. Conclusion: Anethum possesses antioxidative and free radical scavenging properties. This oil chelates ferrous ions and superoxide radicals. It is effective in formation of reactive toxic products. Anethum has good potentials regarding its applications in food and drug industries.
Effects of Copper and Superoxide Dismutase Content of Seminal Plasma on Buffalo Semen Characteristics  [PDF]
M. Eghbali,S.M. Alavi-Shoushtari,S. Asri Rezaii
Pakistan Journal of Biological Sciences , 2008,
Abstract: To investigate the effects of copper and superoxide dismutase (SOD) content of seminal plasma on buffalo semen characteristics, 54 semen samples collected from buffalo bulls by a bovine artificial vagina were used. Semen characteristics (motility, viability, morphology, concentration and volume) were recorded. Seminal plasma was harvested by centrifugation and kept frozen until analysis. Seminal plasma copper content was determined by atomic absorption procedure and SOD was measured by using a kit. The mean total copper value of seminal plasma was recorded as 2.51 ± 0.04 mg kg-1 (Mean ± SEM) and the mean total SOD values was 39.02 ± 0.81 IU mL-1. To reduce the range of variability, the data were categorized according to their motility records in 3 groups of Excellent (Ex, >90% motile, n = 33), Good (Go, 80-89% motile, n = 15) and Moderate (Mo, <79% motile, n = 6). The mean motility, viability, copper and SOD values in Ex group was recorded as 92.24 ± 0.51%, 94.00 ± 0.48%, 2.56 ± 0.04 mg kg-1 and 39.52 ± 0.57 IU mL-1, respectively. These values were 81.66 ± 0.62%, 85.26 ± 0.95%, 2.38 ± 0.11 mg kg-1 and 36.48 ± 1.51 IU mL-1 in Go group and 71.66 ± 1.05%, 77.00 ± 2.94%, 2.55 ± 0.10 mg kg-1 and 50.66 ± 2.51 in Mo group, respectively. The mean copper value in Ex group was highly (r = 0.600) correlated with SOD and correlated with sperm motility (r = 0.372) and viability (r = 0.363), while, in Go group it was highly correlated (r = 0.945) with SOD and sperm viability (r = 0.652) and in Mo group it was correlated (r = 0.874) with semen volume only. The mean SOD values in Ex group was highly correlated with sperm motility (r = 0.492) and viability (r = 0.490) and mean copper values, in Go group, it was highly correlated whit sperm viability (r = 0.659) and mean copper values and in Mo group it had no significant correlations with semen parameters. These results suggest that copper and SOD content of the buffalo seminal plasma have an influence on the sperm motility and viability which are the most important factors in semen fertility.
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