• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2405-2409
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• 2011

The psychrophilic bacteria Psychromonas arctica survives at subzero temperatures by having adapted several protective mechanisms against freezing and oxidative stresses. Many reactive oxygen species are likely generated in P. arctica as a result of reduced metabolic turnover rates. A previous study identified the pasod gene for superoxide dismutase from P. arctica using a series of PCR amplifications. Here, upon cloning into a His-tag fused plasmid, the sod gene from P. arctica (pasod) was successfully expressed by IPTG induction. His-tagged PaSOD was subsequently purified by $Ni^{2+}$-NTA affinity chromatography. The purified PaSOD exhibited a higher SOD activity than that of Escherichia coli (EcSOD) at all temperatures. The difference in activity between PaSOD and EcSOD becomes even more significant at 4$^{\circ}C$, indicating that PaSOD plays a functional role in the cold adaptation of P. arctica in the Arctic.

• Natural Product Sciences
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• v.13 no.1
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• pp.40-45
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• 2007

The methanol extract of Coscinium fenestratum, commonly own as tree turmeric, which is widely used in the indigenous system of medicine was studied for its in vitro scavenging activity in different methods viz DPPH scavenging, nitric oxide scavenging, iron chelation activity, superoxide scavenging, ABTS radical scavenging and lipid peroxidation. The results were analyzed statistically by regression method. Its antioxidant activity was estimated by $IC_{50}$ value and the values are $57.1\;{\mu}g/ml$ for DPPH radical scavenging, $36.5\;{\mu}g/ml$ for iron chelating activity, $51.7\;{\mu}g/ml$ for nitric oxide scavenging, $53.63\;{\mu}g/ml$ for ABTS scavenging, $44.2\;{\mu}g/ml$ for superoxide scavenging, and $40\;{\mu}g/ml$ for lipid peroxidation. In all the methods, the extract showed its ability to scavenge free radicals in a concentration dependent manner. The results indicate that C. fenestratum has potent antiofidant activity.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.10a
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• pp.388-390
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• 2004

본 연구는 자돈 설사의 원인이 되는 대장균, 살모넬라 등 그람음성균을 억제할 수 있는 유산균의 이용을 위해 선발된 균주의 과산화수소 대사를 구명하기 위해 수행하였다. 대장균 억제유산균중 superoxide dismutase 활성이 우수한 균주가 관찰되었으며, 과산화수소 이외에 그람음성균 억제에 유효한 bacteriocin-like compounds의 존재 유무, 대사과정에서 과산화수소 생성과 관련된 다른 효소 활성, superoxide dismutase 유전자 클로닝에 관한 연구가 진행중이다.

• Natural Product Sciences
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• v.17 no.2
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• pp.142-146
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• 2011

In the course of screening for antioxidant compounds by measuring the radical scavenging effect on 1,1-diphenyl- 2-picrylhydrazyl (DPPH), a total extract from the whole plant of Veronica peregrina (Scrophulariaceae) was found to show potent antioxidant activity. Subsequent activity-guided fractionation of the methanolic extract led to the isolation of six phenolic compounds including chrysoeriol (1), diosmetin (2), 4-hydroxybenzoic acid (3), apigenin (4), caffeic acid methylester (5) and protocatechuic acid (6). Their structures were elucidated by spectroscopic studies. Compounds 1-5 were isolated for the first time from this plant. Compounds 5 and 6 showed significant antioxidative effects in DPPH free radical scavenging and superoxide quenching activity assays.

• Archives of Plastic Surgery
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• v.40 no.5
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• pp.517-521
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• 2013

Background Diabetes is characterized by chronic hyperglycemia, which can increase reactive oxygen species (ROS) production by the mitochondrial electron transport chain. The formation of ROS induces oxidative stress and activates oxidative damage-inducing genes in cells. No research has been published on oxidative damage-related extracellular superoxide dismutase (EC-SOD) protein levels in human diabetic skin. We investigated the expression of EC-SOD in diabetic skin compared with normal skin tissue in vivo. Methods The expression of EC-SOD protein was evaluated by western blotting in 6 diabetic skin tissue samples and 6 normal skin samples. Immunohistochemical staining was also carried out to confirm the EC-SOD expression level in the 6 diabetic skin tissue samples. Results The western blotting showed significantly lower EC-SOD protein expression in the diabetic skin tissue than in the normal tissue. Immunohistochemical examination of EC-SOD protein expression supported the western blotting analysis. Conclusions Diabetic skin tissues express a relatively small amount of EC-SOD protein and may not be protected against oxidative stress. We believe that EC-SOD is related to the altered metabolic state in diabetic skin, which elevates ROS production.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.149-149
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• 1993

목적:동식물세포에는 superoxide(0$_{-2}$)의 불균화 반응을 촉매하는 superoxide dismutase (SOD)가 존재한다. 이 효소의 생리적 의의는 지금까지도 명확하게 되어있지 않는면이 많지만, 그 의의를 명확하게 하기위해서도 측정법의 확립이 필요하다. 방법: SOD측정 방법으로는 1) Cytochrome C method 2) Nitroblue tetrazoliun method (NBT법) 3) 면역학적 방법 4) 화학발광법 등이 있다. 실험 재료는 흰쥐, mouse, 토끼의 간을 이용하였으며, 또한, 노화 및 암세포를 이용한 방법을 이용하였다. 결과: Cytochrome C 방법을 통해서 각 장기조직 (신장, 간장, 폐)에서 SOD를 측정하였으며 SOD 활성이 낮은 암조직이나 배양세포에서는 NBT 방법이 측정방법으로 적합한 것으로 나타났으며 ,간장세포내에서의 SOD의 존재부위를 확인하는 방법으로는 면역 황금 표지방법을 사용하므로 간장 mitochondria 내에 Cu, Zn-SOD가 존재함을 알 수 있었다.

• Analytical Science and Technology
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• v.8 no.4
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• pp.649-654
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• 1995

The reactivity of superoxide ion($O{_2}^{-.}$) with halogenated substrates is investigated by cyclic voltammetry and rotated ring-disk electrode method in aprotic solvents. The more positive the reduction potential of the substituted nitrile, the more facile is nucleophilic displacement by $O{_2}^{-.}$. The reaction rates of halogenonitriles with $O{_2}^{-.}$ vary according to the leaving-group propensity of halide (Br>Cl>F). The relative reaction rates of other substituted nitriles are in the order of electron-withdrawing propensity of the substituent group (CN> $C(O)NH_2$ >Ph, $CH_2CN$). The reaction of $O{_2}^{-.}$ with dihalocarbons indicates that five-membered rings can be rapidly formed by the cyclization of substrate and $O{_2}^{-.}$, and the relative rates of cyclization depend on the number of methylenic carbons {$Br(CH_2)_nBr$, [n=1<2<3>4>5]}. Mechanisms are proposed for the reaction of $O{_2}^{-.}$ with halogenated substrates.

• Journal of Microbiology and Biotechnology
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• v.3 no.3
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• pp.188-193
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• 1993

Superoxide dismutase (SOD) was purified from Pseudomonas polycolor to an electrophoretically homogeneous state and partially characterized. SOD was purified by ammonium sulfate fractionation, column chromatography on DEAE-Sephadex A-50, phenyl-Toyopearl 650 M, and gel filtration on Sephadex G-100. The molecular weight and subunit molecular weight of the purified enzyme were estimated to be 40, 000 and 20, 000, respectively. The purified enzyme remained stable at pH 9.0~11.0, $25^{\circ}C$ for 40 hr, but rapidly became inactive below 9.0. SOD was stable up to $45^{\circ}C$ at pH 9.0 with about 80% relative activity, but rapidly became inactive at temperature above that. The enzyme was insensitive to cyanide and fluoride, and sensitive to hydrogen peroxide and azide. The results suggest that the enzyme be an iron-containing SOD.

• Journal of Pharmaceutical Investigation
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• v.25 no.4
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• pp.313-322
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• 1995

The covalent conjugation of human recombinant superoxide dismutase (hrSOD) with trichloros-triazine activated polyethylene glycol (PEG) 5000 formed soluble conjugates with molecular weight of 92KD, which retained $90{\sim}98%$ of original activity with a markedly prolonged plasma half-life of enzyme activity. The effect of hrSOD-PEG conjugates on acetaminophen (ACP)-induced hepatotoxicity was tested in male rats which were pretreated with 3-methylcholanthrene. HrSOD-PEG conjugates inhibited the hepatotoxicity produced by ACP, on the other hand, native hrSOD had no protective effect. The above results indicated that oxygen radicals might participate in the mechanism of the ACP-induced hepatotoxicity and that polymer conjugated-protein drugs with prolonged half-lives could be employed as an effective therapeutic agent.

• Archives of Pharmacal Research
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• v.27 no.6
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• pp.610-614
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• 2004

The in vitro antioxidant properties of some flavone-6(4)-carboxaldehyde oxime ether deriva-tives (Ia-f, lIa-f） were determined by their effects on the rat liver microsomal NADPH-dependent lipid peroxidation (LP） levels by measuring the formation of 2-thiobarbituric acid reactive substances. The free radical scavenging properties of the compounds were also examined in vitro by determining their capacity to scavenge superoxide anions and interact with the stable free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH). The most active compounds, lib (Flavone-4＇-carboxaldehyde-O-ethyl oxime） and Id (Flavone-6-carboxaldehyde-O-［2-(1-pyrolidino） ethyl］ oxime）, caused 98 and 79％ inhibition of superoxide anion production and DPPH stable free radical at $10^{-3}{\;}M$, respectively.