• BMB Reports
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• v.31 no.5
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• pp.492-497
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• 1998

Cu,Zn-superoxide dismutase (SOD) was purified from horseradish by using Mono Q and Superose 12 FPLC column chromatography. The native molecular mass of the purified enzyme was approximately 33 kDa, as determined by gel filtration. The subunit molecular weight, as estimated by SDS-PAGE, was 16 kDa. These results indicated that the native enzyme is a homodimer. We investigated the free radical-generating function of horseradish Cu,Zn-SOD by using a chromogen, 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate) (ABTS) which reacts with ${\cdot}OH$ radicals to form $ABTS^{+{\cdot}}$ The formation of $ABTS^{+{\cdot}}$ was required for both active Cu, Zn-SOD and $H_2O_2$. The optimal pH for the free radical-generating activity of this enzyme was 6.0-8.0, and it retained about $40^{\circ}C$ of its maximum activity when exposed at $40^{\circ}C$ for 15 min. A neutral scavenger, ethanol, inhibited the $ABTS^{+{\cdot}}$ formation by horseradish Cu, Zn-SOD more effectively than that by the mammalian enzyme. These results suggest that the active channel of horseradish enzyme is slightly larger than that of the mammalian enzyme.

• Korean Journal of Pharmacognosy
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• v.51 no.3
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• pp.192-198
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• 2020

Caenorhabditis elegans model system was used to investigate the antioxidant activity of Beta vulgaris L. (Chenopodiaceae) methanol extract. The methanol extract showed DPPH radical scavenging and superoxide quenching activity in a dose-dependent manner. The B. vulgaris methanol extract was measured for the activity of superoxide dismutase (SOD), catalase, and oxidative stress tolerance by using C. elegans, along with reactive oxygen species (ROS) level. In addition, to see that the regulation of the stress response gene is responsible for the increased stress tolerance of C. elegans treated by the methanol extract, SOD-3 expression was measured using a transgenic strain. As a result, the B. vulgaris methanol extract increased SOD and catalase activities, and decreased ROS accumulation, dose-dependently. Furthermore, the methanol extract-treated CF1553 worm showed higher SOD-3::GFP intensity than the control.

• Toxicological Research
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• v.28 no.1
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• pp.19-24
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• 2012

In the present study, toxicity of silver nanoparticles (AgNPs) was investigated in the nematode, Caenohabditis elegans focusing on the upstream signaling pathway responsible for regulating oxidative stress, such as mitogen-activated protein kinase (MAPK) cascades. Formation of reactive oxygen species (ROS) was observed in AgNPs exposed C.elegans, suggesting oxidative stress as an important mechanism in the toxicity of AgNPs towards C. elegans. Expression of genes in MAPK signaling pathways increased by AgNPs exposure in less than 2-fold compared to the control in wildtype C.elegans, however, those were increased dramatically in sod-3 (gk235) mutant after 48 h exposure of AgNPs (i.e. 4-fold for jnk-1 and mpk-2; 6-fold for nsy-1, sek-1, and pmk-1, and 10-fold for jkk-1). These results on the expression of oxidative stress response genes suggest that sod-3 gene expression appears to be dependent on p38 MAPK activation. The high expressions of the pmk-1 gene 48 h exposure to AgNPs in the sod-3 (gk235) mutant can also be interpreted as compensatory mechanisms in the absence of important stress response genes. Overall results suggest that MAPK-based integrated stress signaling network seems to be involved in defense to AgNPs exposure in C.elegans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1578-1582
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• 2007

Contents in polyphenol and vitamin C and their antioxidant activities during storage of Lycii folium prepared by different treatment methods were investigated. The antioxidant activity of extracts prepared from 80% MeOH was evaluated using DPPH radical scavenging and SOD-liked activities. Total phenolic acid contents were 1.34 mg/mL when dry, but extracts during 15-day storage after NaCl 0% treatment decreased. DPPH radical scavenging activity of extracts was 65.48% when dry and decreased during 15-day storage after dry and NaCl 0% treatment. SOD-liked activity was 98.63% in NaCl 0% during 15-day storage after dry. Contents of vitamin C decreased during 15-day storage after dry and NaCl 0% treatment. Consequently, our results indicate that Lycii folium prepared from dry treatment could be a promising biomaterial for the production of functional food for total phenolic acid and vitamin C.

• International Journal of Oral Biology
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• v.30 no.4
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• pp.117-123
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• 2005

Various aspects of antioxidant activity in vitamin C were evaluated in this study. Relatively high level of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was detected in vitamin C, but not in non-antioxidative vitamin, vitamin B1. Vitamin C also reduced the production of lipid peroxidation in Chinese hamster lung fibroblast (V79-4) cells with $IC_{50}$ value of $4{\mu}g/ml$. Vitamin B1 showed comparable reduction in lipid peroxidation products ($IC_{50}$ value was about $10{\mu}g/ml$). It was shown that vitamin C also dose-dependently enhanced the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in V79-4 cells, and these effects were not observed in vitamin Bl-treated cells. Our data suggest that well-known antioxidant vitamin C involved in direct activation of SOD, CAT and GPX.

• Journal of Nutrition and Health
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• v.33 no.5
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• pp.507-516
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• 2000

The purpose of this study was to investigate the effect of vitamin C and vitamin E supplementation on the iron contents and oxidative stress of the rats. Rats were fed 18g ascorbic acid and 300IU $\alpha$-tocopherol/kg diet, respectively. Rats were sacrificed at 1, 3, 5 and 7 month of age. The blood, liver and brain were selected for the quantitation of iron and malondialdehyde(MDA) contents, glutathione peroxidase(GSHPx), superoxided dismutase(SOD) and catalase(CAT) activity. Iron and MDA contents and GSHPx activities were increased with aging. Vitamin C and Vitamin E supplementation increased iron contents of the plasma. Vitamin C raised iron contents, but vitamin E decreased iron contents of the liver. In the brain vitamin C and vitamin E did not affect the iron level. MDA levels were decreased with vitamin C and vitamin E supplementation in the erythrocyte and liver, and vitamin C supplementation elevated MDA levels in the brain. GSHPx activity was increased with vitamin C and vitamin E supplementation. SOD activities of erythroucyte and brain were not affected with age, but in the liver, SOD activity was raised with age and vitamin C supplementation. Vitamin C and vitamin E supplementation promoted CAT activity of erythroucyte and liver, and CAT activity of brain was eleveated with vitamin addition but was decreaed with vitamin E addition. Vitamin C and vitamin E decreased iron contents of blood plasma, MDA contents of plasma and liver, and CAT activity of erythrocyte. Above results indicated that iron contents and biomarkers of oxidative stress were more affected by age than antioxidant action of vitamin C and vitamin E.

• BMB Reports
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• v.38 no.5
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• pp.533-538
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• 2005

The kinetics of thermal dissociation of superoxide dismutase (SOD) was studied in 0.05 M Tris-HCl buffer at pH 7.4 containing $10^{-4}\;M$ EDTA. The number of conformational locks and contact areas and amino acid residues of dimers of SOD were obtained by kinetic analysis and biochemical calculation. The cleavage bonds between dimers of SOD during thermal dissociation and type of interactions between specific amino acid residues were also simulated. Two identical contact areas between two subunits were identified. Cleavage of these contact areas resulted in dissociation of the subunits, with destruction of the active centers, and thus, lost of activity. It is suggested that the contact areas interact with active centers by conformational changes involving secondary structural elements.

• Natural Product Sciences
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• v.25 no.3
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• pp.255-260
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• 2019

Piper nigrum L. (Piperaceae), which is a well-known food seasoning, has been used as a traditional medicine for the treatment of vomiting, abdominal pain, diarrhea and anorexia in Korea, China and Japan. Methanol extract from the fruit of P. nigrum was successively partitioned as n-hexane, methylene chloride, ethyl acetate, n-butanol and $H_2O$ soluble fractions. Among those fractions the ethyl acetate soluble fraction showed the most potent DPPH radical scavenging activity, and piperine was isolated from the ethyl acetate fraction. To know the antioxidant activity of piperine, we tested the activities of superoxide dismutase (SOD) and catalase together with oxidative stress tolerance and intracellular ROS level in Caenorhabditis elegans. To investigate whether piperine-mediated increased stress tolerance was due to regulation of stress-response gene, we quantified SOD-3 expression using transgenic strain including CF1553. Consequently, piperine enhanced SOD and catalase activities of C. elegans, and reduced intracellular ROS accumulation in a dose-dependent manner. Moreover, piperine-treated CF1553 worms exhibited significantly higher SOD-3::GFP intensity.

• BMB Reports
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• v.44 no.1
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• pp.40-45
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• 2011

Extracellular superoxide dismutase (EC-SOD) is an antioxidant enzyme that protects cells and tissues from extracellular damage by eliminating superoxide anion radicals produced during metabolism. Two different forms of EC-SOD exist, and their different enzyme activities are a result of different disulfide bond patterns. Although only two folding variants have been discovered so far, five folding variants are theoretically possible. Therefore, we constructed five different mutant EC-SOD expression vectors by substituting cysteine residues with serine residues and evaluated their expression levels and enzyme activities. The mutant EC-SODs were expressed at lower levels than that of wild-type EC-SOD, and all of the mutants exhibited inhibited extracellular secretion, except for C195S ECSOD. Finally, we demonstrated that co-expression of wild-type EC-SOD and any one of the mutant EC-SODs resulted in reduced secretion of wild-type EC-SOD. We speculate that mutant EC-SOD causes malfunctions in systems such as antioxidant systems and sensitizes tissues to ROS-mediated diseases.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.1
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• pp.1-13
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• 2016

Physiological response of fish and bivalve was estimated to identify the physiological changes of test species by lowering water temperature due to the abrupt stop of cooling water discharge from power plant. The experiment was conducted by two conditions; fall and winter by decreasing water temperature ($2^{\circ}C$/2 days) from $26^{\circ}C$ to $17^{\circ}C$ for fall scenario and from $15^{\circ}C$ to $9^{\circ}C$ for winter scenario, respectively. Test organisms were parrot fish (Oplegnathus fasciantus) and bivalve (Gomphina melanaegis), and end points were mortality for both species, hematocrit and cortisol for fish, and hemolymph and superoxide dismutase(SOD) for bivalve. 48/96hr mortality test revealed no mortality for fish and 47% mortality for bivalve at 96hr/$26^{\circ}C$ only. Significant increases of hematocrit and cortisol were found at fishes exposed to $26^{\circ}C$ (high temperature) and lower temperature ($9{\sim}13^{\circ}C$), respectively. Hemolymph and SOD for bivalve tended to decrease by lowering water temperature from 15 to $9^{\circ}C$ (winter scenario) and no changes from 26 to $17^{\circ}C$ (fall scenario). Fall scenario (from 15 to $9^{\circ}C$) showed more significant changes of physiological response than winter cases (26 to $17^{\circ}C$).