• BMB Reports
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• 제32권2호
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• pp.161-167
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• 1999

The role of oxidative stress in the initiation and the complication of diabetes was examined by monitoring blood glucose increase and oxidative DNA damage in rats treated with alloxan or streptozotocin (STZ). Oxidative DNA damage was assessed by quantitating 8-oxo-2'-deoxyguanosine ($oxo^8dG)$ excreted in urine and the $oxo^8dG$ accumulated in pancreas DNA. Both alloxan and STZ treatments resulted in an abrupt increase in blood glucose and significant increases in urinary and pancreatic $oxo^8dG$. Pretreatment of buthionine sulfoximine (BSO), a glutathione-depleting agent, slightly potentiated the increase of blood glucose and urinary $oxo^8dG$ in the alloxan- and STZ-treated rats. Furthermore, the BSO pretreatment caused significant amplification of pancreatic $oxo^8dG$ increase in the rats. On the other hand, pretreatment with 1,10- phenanthroline (o-phen), a chelator of divalent cations, showed different results between alloxan- and STZ-treated rats. The o-phen pretreatment completely blocked diabetes and the increase of $oxo^8dG$ by alloxan treatment, while it potentiated the increase of blood glucose and $oxo^8dG$ by STZ treatment. The results demonstrate that the causative effect of alloxan on diabetes may be the generation of reactive oxygen species through a Fenton type reaction, but that of STZ may not.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2012년도 제46차 학술발표회
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• pp.118-118
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• 2012

현재 정부는 친환경녹색성장을 모티브로 환경기준을 강화하고 있으며, 오염 발생원을 최소화 하고자 현재 가동중인 환경기초시설을 대상으로 고도산화공정을 추가하여 오염 배출량을 최소화 하도록 정부와 지자체가 독려하고 있는 중이다. 따라서 대표적인 환경오염 업종인 섬유/염색 관련업체는 강화되는 환경기준을 만족하기 위한 공정검토가 불가피한 현실이다. 특히 대구 OO염색공단은 염색업체가 집적되어 있어 난분해성 오염물질과 색도유발물질이 다량 발생되고 있으며, 폐수처리장에서 운영 중인 재래식 폐수처리공정으로는 강화되는 방류수 수질기준을 충족할 수 없다. 따라서 본 연구에서는 방류수 수질기준을 만족하기 위한 고도산화 공정을 검토하였으며, 그 공정의 최적인자를 도출하고자 하였다. 고도산화 공정에서 오존산화, Peroxone AOP, Fenton oxidation 공정을 검토하였으며, 강화되는 수질기준을 만족할 수 있는 최적인자 및 처리효율을 검토하였다. 그 결과 조건에 따라 COD, T-N, T-P, 색도 등에서 처리효율은 40 ~ 90% 범위로 경제성을 고려하여 최적의 운전조건을 도출 하였다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.58-59
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• 2006

Less than a decade ago, most alternate membrane materials for fuel cells relied upon a post-sulfonation process to generate ionic groups capable of transporting protons from the anode to the cathode. These random post sulfonations showed some promise, but in general they produced materials that were not sufficiently stable or protonically conductive at ion exchange capacities where aqueous swelling could be restricted. Our group began to synthesize disulfonated monomers that could be used to incorporate into random copolymer proton exchange membranes. The expected limitation was that the aromatic polymers might not be stable enough to withstand fuel cell conditions. However, this was mostly based upon an accelerated test known was the Fenton's Reagent Test, which did not seem to this author as being a reliable predictor of performance. A much better approach has been to evaluate the open circuit voltage (OCV) for alternate membranes, as well as the benchmark perfluorosulfonic acid systems. When this is done, the aromatic ionomers of this study, primarily based upon disulfonated polyarylene ether sulfones, show up quite well. Real time 3000 hours DMFC results have also been generated. Obtaining conductive materials at low humidities is another major issue where alternate membranes have not been particularly successful. In order to address this problem, multiblock copolymers with relatively high water diffusion coefficients have been designed, which show promise for conductivity at lowered humidity.

• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 1993년도 정기총회 및 제3차 학술발표회
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• pp.10-11
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• 1993

기저상태의 산소분자는 비교적 안정하지만 생체ㅇ내외에서 물리적, 화학적으로 활성화 되어 $O_{2}$, $^{1}O_{2}$, OH, $H_{2}O_{2}$ 등의 활성산소종을 생성하며, 생체의 지질, 단백질, 핵산 당등의 분자에 산화적 상해를 초래하여 노화, 암, 순환기, 호흡기 게통의 질환과 식품의 품질열화에 관여하는 것으로 알려져 있다. 따라서 본인은 식품의 맛, 향기, 색 등을 부여하는 고유의 기능 외에도 방부제, 한방약으로 널리 이용되고 오고 있는 51종의 향신료를 대상으로 활성산소포촉활성을 조사하고 나아가 활성물질을 분리, 정제 및 동정함으로 향신료의 새로운 기능을 밝히고 신약 개발의 기초적 자료를 제시하고저 한다. Fenton 반응을 이용하여 2-deozyribose 산화법과 sodium benzoic acid 수산화법으로 51종의 향신료의 OH 포촉활성을 검색한 결과, Cruciferae과의 nustard 류, Labiatae과의 thyme, saga, savory, oregano, Myrtaceae과의 clove, allspice 가 1ug/ml 농도에서 50%이상의 포촉활성을 나타내었으며 그중 mustard 류는 같은 농도에서 거의 90%이상의 활성을 나타내었다. 활성물질의 분리 및 정제는 Amberlite XAD-2 갈럼과 preparative-HPLC를 이용 하였으며, EI, FAB-MS, IR, $^{1}H$, $^{13}C-NMR$, Cosy-NMR로 그 화학적 구조를 동정하였다. Brown mustard에서 동정된 4-hydroxy-3,5-dimethoxy cinnamic acid Methyl ester는 0.42$\mu$ mol 농도에서 90% 이상의 OH 포촉활성을 나타내어 이를 diazomethane 반응으로 조제하였으며 white mistard에서는 4-hydroxy-3,5-dimethoxy cinnamoyl choline을 동정하였다.

• Bulletin of the Korean Chemical Society
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• 제28권12호
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• pp.2329-2332
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• 2007

Salsolinol, endogenous neurotoxin, is known to be involved in the pathogenesis of Parkinson's disease (PD). In the present study, we have investigated the oxidative damage of DNA induced by the reaction of salsolinol with Cu,Zn-SOD. When plasmid DNA incubated with salsolinol and Cu,Zn-SOD, DNA cleavage was proportional to the concentrations of salsolinol and Cu,Zn-SOD. The salsolinol/Cu,Zn-SOD system-mediated DNA cleavage was significantly inhibited by radical scavengers such as mannitol, ethanol and thiourea. These results indicated that free radicals might participate in DNA cleavage by the salsolinol/Cu,Zn-SOD system. Spectrophotometric study using a thiobarbituric acid showed that hydroxyl radical formation was proportional to the concentration of salsolinol and was inhibited by radical scavengers. These results indicated that hydroxyl radical generated in the reaction of salsolinol with Cu,Zn-SOD was implicated in the DNA cleavage. Catalase and copper chelators inhibited DNA cleavage and the production of hydroxyl radicals. These results suggest that DNA cleavage is mediated in the reaction of salsolinol with Cu,Zn-SOD via the generation of hydroxyl radical by a combination of the oxidation reaction of salsolinol and Fenton-like reaction of free copper ions released from oxidatively damaged SOD.

• 한국세라믹학회지
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• 제47권2호
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• pp.169-176
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• 2010

The Fe-treated CNT/$TiO_2$ photocatalysts mixed with anatase and rutile phase have been developed for the decomposition of non-biodegradable different organic dyes like methylene blue (MB), rhodamine B (Rh.B), and methyl orange (MO) in two conditions as ultraviolet and visible light respectively. The results indicate that all the Fe-CNT/$TiO_2$ composites proved to be more efficient photocatalysts since degradation of MB at higher reaction rates, tthe decomposition rate of different dyes increases with an increase of $Fe^{3+}$ concentration in composites the highest rate of decomposition of different dyes was noted under UV irradiation. These results can indicate that the large CNT network is facilitate the electron transfer and strongly adsorb dye molecules on the texted photocatalysts, iron is reactive in the photo-Fenton process resulting in high production of OH radicals and also high activity of the photocatalyst. And Fe particles can generate more photoinduced electrons to conduction band of $TiO_2$ under visible light irradiation. The composites of Fe-CNT/$TiO_2$ photocatalysts synthesized by a sol-gel method were characterized by BET, TEM, SEM, XRD and EDX.

• 한국수소및신에너지학회논문집
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• 제29권4호
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• pp.331-338
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• 2018

In this study, sulfonated PAES block copolymers have been synthesized via nucleophilic substitution reaction. Hydrophobic oligomer was prepared using 2,6-dihydroxynaphthalene and bis(4-chlorophenyl) sulfone, whereas hydrophilic oligomer was prepared using sulfonated bis(4-chlorophenyl) sulfone and bis(4-hydroxyphenyl) sulfone. The chemical structure of polymers was analyzed by $^1H$ NMR, FT-IR and GPC. The thermal properties of polymers were measured by TGA and DSC. The oxidative stability of membranes was investigated by Fenton's test. Furthermore, the proton conductivity of membrane was found to be 26 mS/cm at $90^{\circ}C$. All physiochemical properties suggest that fabricated membrane have a great potential for applications in PEMFC.

• Advances in Traditional Medicine
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• 제7권1호
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• pp.65-73
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• 2007

Water and alcohol extracts were prepared from dried and powdered leaves of Thuja orientalis (T. orientalis). The reducing power, total phenolic content, the 1,1-diphenyl-2-picrylhydrazyl scavenging activity, inhibitory effect on Fe (II)-EDTA-$H_{2}O_{2}$ (Fenton reaction system) induced DNA damage and inhibitory effect on human red blood cell (RBC) hemolysis were evaluated in the present study. At a concentration of 200 mg, water and alcohol extracts of T. orientalis inhibited the hydrolysis of DNA by 72.859% and 65.312%, respectively. Water and alcohol extracts of T. orientalis also inhibited 2,2'-Azobis(2-amidinopropane) dihydrochloride induced RBC hemolysis to the extent of 69.30% and 54.55%, respectively. The reducing power and antioxidative activity of water extract was found to be more than that of alcohol extract. This is attributable to the presence of higher amount of phenolic compounds in water extract. The present results indicate that the T. orientalis extracts are rich sources of natural antioxidants and can protect DNA and human red blood cells against free radical induced oxidative damage.

• 동의생리병리학회지
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• 제23권4호
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• pp.872-882
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• 2009

Sachil-Tang (SCT) has been traditionally used as a prescription of spasm of the esophagus by stress, pectoralgia and oppressive feeling of the chest in Oriental medicine. This study was carried out to investigate the antioxidant activities of the ethanol extract of SCT and its inhibitory effect on intracellular oxidation and vascular cell adhesion molecule-1 expression in human umbilical vein endothelial cells (HUVECs) using various methods. The SCT extract showed a strong inhibitory effect on free radical generating model systems, including DPPH radical, superoxide anions, hydroxyl radical, peroxynirite and nitric oxide. Besides, the SCT extract exhibited a strong inhibitory effect on lipid peroxidation in rat liver homogenate induced by $FeCl_2$-ascorbic acid, and protected plasmid DNA against the strand breakage in a Fenton's reaction system. The SCT extract also inhibited copper-mediated oxidation of human low-density lipoprotein (LDL), and repressed relative electrophoretic mobility of LDL. Furthermore, the SCT extract protected intracellular oxidation induced by various free radical generators and inhibited expression of vascular cell adhesion molecule-1 (VCAM-1) in HUVECs. These results suggest that SCT can be an effective natural antioxidant and a possible medicine of atherosclerosis.

• Archives of Pharmacal Research
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• 제25권3호
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• pp.313-319
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• 2002

A total of eight flavonoids (1-8), including a novel $quercetin-7-o-(6"-o-acetyl)-{\beta}-D-glucopyranoside$ (6) and seven known flavonoids, luteolin (1), quercetin (2), luteolin $7-o-{\beta}-D-glucopyranoside$ (3), $luteolin-7-o-(6"-Ο-acetyl)-{\beta}-D-glucopyranoside$ (4) quercetin $7-o-{\beta}-D-glucopyranoside$ (5), acacetin 7-o-{\beta}-D-glucuronide (7) and apigenin-6-C-{\beta}-D-glucopyrano $syl-8-C-{\beta}-D-glucopyranoside$ (8), have been isolated from the leaves of the safflower (Carthamus tinctorius L.) and identified on the basis of spectroscopic and chemical studies. The antioxidative activity of these flavonoids was evaluated against 2-deoxyribose degradation and rat liver microsomal lipid peroxidation induced by hydroxyl radicals generated via a Fenton-type reaction. Among these flavonoids, luteolin-acetyl-glucoside (4) and quercetin-acetyl-glucoside (6) showed potent antioxidative activities against 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. Luteolin (1), quercetin (2), and their corresponding glycosides (3 & 5) also exhibited strong antioxidative activity, while acacetin glucuronide (7) and apigenin-6,8-di-C-glucoside (8) were relatively less active.