• 한국식품저장유통학회:학술대회논문집
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• 한국식품저장유통학회 2003년도 춘계총회 및 제22차 학술발표회
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• pp.110.2-111
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• 2003

삼백초 지상부를 탈지후 60% acetone으로 추출하고 이를 극성에 따라 diethyl ether, ethyl acetate, aqueous fraction과 같이 용매분획하였다. 각 fraction의 superoxide anion, hydrogen peroxide, hydroxyl radical, DPPH radical 에 대한 소거활성을 측정하였다. Diethyl ether fraction의 ROS 소거효과가 비교적 강하였으며 superoxide anion 소거활성은 100ppm에서 86.88%였고, hydroxyl radical 소거활성은 1ppm에서 85.3%로 나타났다. Hydrogen peroxide, DPPH radical 소거활성은 ethyl acetate fraction이 강하게 나타났다. Diethyl ether fraction으로부터 silica gel column chromatography, sephadex LH-20 column chromatography, preparative HPLC에 의하여 수 종의 성분을 분리하였으며 현재 구조동정과 이들의 LDL산화억제 효과 시험 중에 있다.

• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.935-938
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• 1999

Reactivity and reaction mechanism for the reactions of 1,1'-(azodicarbonyl) dipiperidine with triphenylphosphines are investigated using kinetic method. The cation radical, Ph3P and the anion radical, -N-N - are produced during the course of the reaction. The cation radical is formed by the transfer of an electron from phosphorus to the nitrogen atom. The anion radical is formed by the addition of the one electron to the azo rad-ical. The rate constants are decreased by electron withdrawing groups while they are increased by electron donating groups present in triphenylphosphine. The electron density increases on nitrogen, while positive charge is developed on phosphorus in the transition state.

• 한국식품과학회지
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• 제51권2호
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• pp.133-140
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• 2019

Antioxidant activities of Ulmus davidiana root and bark extracts were evaluated by various antioxidant tests, including DPPH radical-scavenging, nitric oxide-scavenging, superoxide anion radical-scavenging, and ABTS radical-scavenging assays, and superoxide dismutase (SOD)-like activity and reducing power analysis, along with the determination of total phenolic and flavonoid contents. Both the extracts showed strong antioxidant activities by these testing methods. Ulmus davidiana root extract possessed strong reducing power and nitric oxide-scavenging activity, and high scavenging activities against free radicals including the superoxide anion, and the ABTS and DPPH radicals, but a weaker scavenging activity of SOD. In contrast, the Ulmus davidiana bark extract exhibited a strong SOD-like activity, but all the other activities were weak. It was observed that the total phenolic and flavonoid contents of the Ulmus davidiana root extract were higher than those of the Ulmus davidiana bark extract.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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• pp.100-103
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• 2000

In the case of immobilizing of glucose oxidase into polypyrrole (PPy) using electrosynthesis, the glucose oxidase (GOx) forms a coordinate bond with the polymers backbone. However, because of intrinsic insulation and net-chain of the enzyme, the charge transfer and mass transport are obstructed during the film growth. Therefore, the film growth is dull. We synthesized the enzyme electrode by electropolymerization added some organic solvent. A formative seeds of film growth is delayed by adding ethanol. The delay is induced by radical transfer between ethanol and pyrrole monomer. The radical transfer shares the contribution of dopant between electrolyte anion and GOx polyanion. This may lead to increase amount of immobilized the enzyme in PPy. For the UV absorption spectra of synthetic solution before synthesis and after, in the case of ethanol added, the optical density was slightly decreased for the GOx peaks. It suggests amount of GOx in the solution was decreased and amount of GOx in the film was increased. We established qualitatively that amount of immobilization can be improved by adding a little ethanol in the synthetic solution. It is due to radical transfer reaction. The radical transfer shares the contribution of dopant between small and fast electrolyte anion and big and slow GOx polyanion.

• Archives of Pharmacal Research
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• 제27권4호
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• pp.390-395
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• 2004

The methanol extract obtained from the aerial parts of Aceriphyllum rossii (Saxifragaceae) was fractionated into ethyl acetate (EtOAc), n-BuOH and $H_2O$ layers through solvent fractionation. Repeated silica gel column chromatography of EtOAc and n-BuOH layers afforded six flavonol glycosides. They were identified as kaempferol 3-O-$\beta$-D-glucopyranoside (astragalin, 1), quercetin 3-O-$\beta$-D-glucopyranoside (isoquercitrin, 2), kaempferol 3-O-$\alpha$-L-rhamnopyranosyl $(1{\to}6)-\beta$-D-glucopyranoside (3), quercetin 3-O$\alpha$-L-rharnnopyranosyl $(1{\to}6)-\beta$-D-qlucopyrano-side (rutin, 4), kaempferol 3-O-[$\alpha$-L-rharnnopyranosyl $(1{\to}4)-\alpha$-L-rhamnopyranosyl $(1{\to}6)-\beta$-D-glucopyranoside] (5) and quercetin 3-O-[$\alpha$-L-rhamnopyranosyl $(1{\to}4)\alpha$-L-rhamnopyranosyl $(1{\to}6)\beta$-D-glucopyranoside] (6) on the basis of several spectral data. The antioxidant activity of the six compounds was investigated using two free radicals such as the ABTS free radical and superoxide anion radical. Compound 1 exhibited the highest antioxidant activity in the ABTS $\{2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)\}$ radical scavenging method. 100 mg/L of compound 1 was equivalent to $72.1\pm1.4\;mg/L$ of vitamin C, and those of compounds 3 and 5 were equivalent to $62.7\pm0.5\;mg/L$ and $54.3\pm1.3\;mg/L$ of vitamin C, respectively. And in the superoxide anion radical scavenging method, compound 5 exhibited the highest activity with an $IC_{50}$ value of $17.6{\pm}0.3{\mu}M$. In addition, some physical and spectral data of the flavonoids were confirmed.

• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.259-265
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• 2008

This study was designed to investigate the protective effect of fucoidan against AAPH-induced oxidative stress in LLC-PK1 cells (porcine kidney epithelial cells). Oxidative stress was induced by exposing of LLC-PK1 cells to the 1 mM 2,2'-azobis(2-amidino propane) dihydrochloride (AAPH) for 24 hr. Exposure of LLC-PK1 cells to 1 mM AAPH for 24 hr resulted in a significant (p<0.05) decrease in cell viability, but fucoidan treatment protected LLC-PK1 cells from AAPH-induced cell damage in a dose dependant manner. To investigate the protective action of fucoidan against AAPH-induced damage of LLC-PK1 cells, we measured the effects of fucoidan on lipid peroxidation and antioxidant enzymes activities of AAPH treated cells as well as scavenging activities on superoxide anion radical and hydroxyl radical. Fucoidan had protective effect against the AAPH-induced LLC-PK1 cellular damage and decreased lipid peroxidation and increased activities of antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-px). Furthermore, fucoidan showed strong scavenging activity against superoxide anion radical. The $IC_{50}$ value of fucoidan was $48.37{\pm}1.54\;{\mu}g/mL$ for superoxide anion radical scavenging activity. The fucoidan also had high hydroxyl radical scavenging activity ($IC_{50}=32.03\;{\mu}g/mL$). These results indicate that fucoidan protects against AAPH-induced LLC-PK1 cell damage by inhibiting lipid peroxidation, increasing antioxidant enzyme activities and scavenging offree radicals.

• Applied Biological Chemistry
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• 제49권4호
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• pp.328-333
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• 2006

많은 식물 추출물들은 항산화 효능을 지니고 있으나 대량 생산 공정시 그들의 활성을 잃어버리는 경향이 있다. 따라서 본 본문에서는 대량 생산 공정을 거쳐 국내 유통 중인 43종의 식용식물 추출물을 대상으로 총 페놀 함량, DPPH 라디칼 포착 효능, 그리고 superoxide anion 라디칼 포착 효능을 측정하였다. 그 결과 개똥쑥(Artemisia annua, whole plant), 마태(Ilex paraguariensis leaf), 엉겅퀴(Silybum marianum, fruit 그리고 leaf), 유근피(Ulmus pumila, bark), 운지버섯(Coriolus versicolor, fruit) 그리고 울금(Curcuma longa, root 그리고 stem) 추출물은 70 mg/g 이상의 높은 페놀화합물을 함유하는 것으로 나타났다. DPPH 라디칼의 포착 효능에서 개똥쑥, 마테, 솔잎(Pinus densiflora, leaf), 엉겅퀴, 유근피, 그리고 울금 추출물의 $SC_{50}$ 값 측정 결과 각각 $53.96{\pm}0.81ppm,\;24.61{\pm}2.12ppm,\;35.96{\pm}1.11ppm,\;57.45{\pm}2.13ppm,\;55.25{\pm}1.65ppm$ 그리고 $12.99{\pm}1.67ppm$으로 나타났다(비타민 C의 $SC_{50}$값: $3.86{\pm}0.81ppm$). 또한 superoxide anion 라디칼 포착 효능에서는 개똥쑥, 계피(Cinnamomum zeylunicum, bark), 마테, 복분자(Rubus coreanus, fruit 그리고 leaf), 상엽(Morus alba, leaf), 솔잎, 엉겅퀴, 유근피, 운지버섯, 울금, 자소엽(Perilla frutescens var. acuta, leaf) 그리고 히비스커스(Hibiscus sabdariffa, leaf) 그리고 flower) 추출물의 $SC_{50}$ 값 측정 결과 각각 $53.21{\pm}1.83ppm,\;50.12{\pm}2.12ppm,\;5.59{\pm}0.84ppm,\;41.60{\pm}8.93ppm,\;20.19{\pm}0.97ppm,\;15.19{\pm}1.66ppm,\;21.20{\pm}1.88ppm,\;15.71{\pm}0.91ppm,\;55.48{\pm}2.42ppm,\;52.12{\pm}2.44ppm,\;23.80{\pm}1.98ppm$ 그리고 $11.14{\pm}0.51ppm$인 것으로 나타났다(비타민 C의 $SC_{50}$ 값:$9.61{\pm}0.93ppm$). 특히 마테 추출물과 솔잎 추출물은 총 페놀 함량이 높으면서 DPPH 라디칼과 superoxide anion 라디칼을 동시에 효율적으로 포착하는 효능을 지니고 있는 것으로 나타났다. 결론적으로 마테와 솔잎의 상업적인 추출물은 기능성 항산화제로서 유용한 소재로 사용 가능 할 것으로 사료된다.

• Journal of Life Science
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• 제12권2호
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• pp.75-79
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• 2002

Tea catechins, the most important compounds in tea polyphenols, can efficiently scavenge superoxide anion free-radical ($O_2$.), hydroxyl radical. (.OH) The mechanism of scavenging active oxygen free radicals was investigated by ESR spin trapping technique and Chemiluminescence. Results showed that various tea catechins constitute an antioxidant cycle in accordance with the decreasing order of the first reductive potential, and produce the effect of cooperative strength each other. Esterificated catechins could scavenge active oxygen free radicals more effectively than the non-esterificated ones. When.OH and $O_2$.- were scavenged by (-)-epigallocatechin gallate [(-)- EGCG], the stoichiometric factors were 6, and the rate constants of scavenging reaction reached $7.71{\times}10^6$ and $3.52{\times}10^{11}$ L $mmol^{-1}s^{-1}$, respectively. In the mean time, tea catechins could scavenge superoxide anion fiee radical ($O_2$-.) and hydroxyl radical (.OH) in a dose dependent manner. But at higher concentration or pH value, tea catechins can induce the prooxidant.

• 한국한의학연구원논문집
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• 제3권1호
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• pp.229-239
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• 1997

The superoxide anion radical$(O_2)$ poses a threat to macromocules and cell organelles of the living cells. This toxicity damage to all groups of proteins results in loss of enzyme function concerned with metabolism and ion transport, and peroxidation of unsaturated fatty acids and cholesterol results in a change of permeability characteristics of the membrane, and oxidative of nucleic acids results in genomic damage and thereby cause mutation, potential carcinogenesis and somatic damage that produce cellular aging Superoxide dismutase(SOD) has received substantial attention as a potential therapeutic agent. It has been investigated as a possible agent for the prevention of ontogenesis, the reduction of cytotoxic effect of anticancer drugs, and protection against damage in ischemic tissue. It is suggest that $O_2$ is concerned with cellular aging, thereafter we need to investigate herb that activated to SOD.

• BMB Reports
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• 제29권5호
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• pp.423-428
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• 1996

A superoxide anion radical scavenger isolated from Capsella bursa-pastoris was characterized by infrared (IR) spectroscopy, sugar analysis, ultraviolet (UV) spectroscopy, $^{1}H$ and $^{13}C$ nuclear magnetic resonance (NMR) spectroscopies, and fast atom bombardment (FAB) mass analysis. The compound was assumed to be a flavonoid-O-glycoside from IR spectrum and UV absorption maxima. When the sugar composition of the compound was examined by thin layer chromatography (TLC) and gas chromatography (GC) of the acid hydrolysate, only glucose was detected. According to the results of UV spectrotroscopy by using shift reagents, the compound was supposed to be luteolin (5,7,3',4'-tetrahydroxy flavone) or chrysoeriol (5,7,4'-trihydroxy-3'-methoxy flavone) with glucose. Based on $^{1}H$- and $^{13}C-NMR$ spectroscopies, the compound was deduced as 7,4'-dihydroxy-5,3'-dimethoxy-${\alpha}$-6-c-glucosyl-${\beta}$-2"-o-glucosyl flavone. In FAB mass analysis the compound was finally characterized as 7,4'-dihydroxy-5,3'-dimethoxy-${\alpha}$-6-c-glucosyl-${\beta}$-2"-o-glucosyl flavone ($C_{29}H_{34}O_{16}$, M.W.=638).