• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.142-145
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• 1999

We confirm that when A-type zeolite supporting silver lone is placed in ion-exchanged distilled water, silver ions is eluted and eluted silver ions generates hydroxyl-radical (.OH) and hydro-radical (.H) continuously, the amount of those is proportion to the silver-ion concentration. Hydroxyl-radical is not generated by super-oxide anion-radical (.O2) but by directly dissolved water. To know such a above discussed mechanism, we prepare A-type zeolite supporting silver ions, and measure the amount of the eluted silver tons by atomic absorption spectroscopy and the generated radical by ESR The radical generated by A-type zeolite supporting silver ions is discussed in the application of elecrical and electronic materials.

• Archives of Pharmacal Research
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• 제27권6호
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• pp.615-618
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• 2004

In the course of screening for reactive oxygen species scavengers from natural products, an antioxidant was isolated from the mycelial culture broth of Phellinus linteus and identified as hispidin. The hispidin content was reached its maximum level at 12 days after onset of inoculation. About 2.5 mg／mL of hispidin was produced by P linteus in a yeast-malt medium (pH 5.8, $25^{\circ}C$). Hispidin inhibited 22.6 and 56.8% of the super oxide anion radical, 79.4 and 95.3% of the hydroxyl radical, and 28.1 and 85.5% of the DPPH radical at 0.1 and 1.0 mM, respectively. The positive control ${\alpha}-tocopherol$ scavenged 25.6 and 60.3%, 74.6 and 96.3%, and 32.7 and 77.5% of each radical, respectively, at the same concentrations. However, hispidin showed no significant activity on the hydrogen peroxide radical.

• Current Research on Agriculture and Life Sciences
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• 제31권2호
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• pp.101-107
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• 2013

This study was undertaken to determine free radical scavenging capacity and oxidative DNA damage protecting activity of methanol extract of red tea stem. The extract was subjected to assess their antioxidant potential using various in vitro systems such as $DPPH^{\bullet}$, $ABTS^{{\bullet}+}$, super oxide and nitric oxide free radicals and it exhibited $IC_{50}$ values of $68.88{\pm}1.1$, $12.08{\pm}0.65$, $404.38{\pm}1.6$, $93.6{\pm}2.7{\mu}g/mL$ respectively. Red tea extract also showed ferric reducing ability (FRAP) with 2606.85 mmol Fe (II)/g of extract. Furthermore, Methanol extract of red tea stem showed significant DNA damage protecting activity in concentration dependent manner against $H_2O_2+UV$ induced photolysis on pUC19 plasmid DNA. Results of this study showed that the methanol extract of Red Tea stem has strong antioxidant potential along oxidative DNA damage protecting capacity that would be the significant sources of natural antioxidants, which might be helpful in preventing the progress of various oxidative stress generated diseases. Further study is necessary for isolation and characterization of the active antioxidants, which may serve as a potential source of natural antioxidant.

• 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.

• Applied Biological Chemistry
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• 제47권2호
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• pp.283-286
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• 2004

In the course of screening for reactive oxygen species scavengers from natural products, two antioxidants were isolated from the edible mushroom Polyozellus multiflex and identified as polyozellin and thelephoric acid. Thelephoric acid inhibited 45.7% of the super oxide anion radical, 74.6% of the hydroxyl radical, and 44.0% of the DPPH radical at 0.1 mM, while the positive control ${\alpha}-tocopherol$ did 22.1%, 75.6%, and 26.5% of each radical, respectively. Polyozellin, the reductive acetylated form of thelephoric acid, showed almost same scavenging activity against above mentioned radicals. The isolated compounds showed scavenging activity on the superoxide anion radical in the ESR method ($IC_{50}$ of polyozellin and thelephoric acid were $218.0\;{\mu}M$ and $21.1\;{\mu}M$, respenctively). However, they showed no significant activity on the hydrogen peroxide radical.

• 한국해양바이오학회지
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• 제2권3호
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• pp.174-186
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• 2007

Amphora coffeaeformis and Achnanthes longipes are commonly found as dominant benthic microalgae in Jeju coastal water throughout the year. In order to investigate pharmaceutical uses of these diatoms, each single species was isolated with micropipette under phase contrast microscope and subcultured with synthetic seawater media which was enriched with F/2 media, trace metal solution and $Na_2SiO_3$). Growth characteristics of these species were also determined with different combination of salinity, nutrients concentration and temperature. Thereafter, mass culture of each species was done based on the maximum growth condition. Biomass was collected after two weeks of mass culture and freeze dried for antioxidant study. The antioxidant properties of different fractions (n-hexane, chloroform and ethylacetate) obtained by solvent fractionation of 80% methanolic extract of two microalgae were investigated for free radical, reactive oxygen species scavenging (Super oxide, Hydrogen peroxide, Hydroxyl radical and Nitric oxide), metal chelating and lipid peroxidation inhibition activities. All fractions of A. longipes showed higher $DPPH^{\cdot}$ (free radical) scavenging activities (n-hexane: 89.0%, Chloroform: 76.0%, Ethylacetate: 66.0%, Methanol: 90.6% and aqueous residue: 63.0%). N-hexane fraction of A. longipes showed significantly higher activity (49.0%) on nitric-oxide. Ethylacetate fraction of A. longipes and aqueous residue of A. coffeaeformis exhibited 64.0% and 75.6% metal chelating activity which was higher than commercial antioxidants (${\alpha}$-tocopherol: 18.0% and BHT: 16.0%). The n-hexane fraction of A. coffeaeformis had 67.5% activity on $DPPH^{\cdot}$. Chloroform and n-hexane fractions of A. coffeaeformis exhibited 46.2% and 47.6% $H_2O_2$ scavenging effects which were closely similar to commercial antioxidants (${\alpha}$-tocopherol: 49.2% and BHT: 58.6%). Chloroform and ethylacetate fractions of A. longipes and fraction of n-hexane and chloroform of A. coffeaeformis showed better lipid peroxidation activities than ${\alpha}$-tocopherol. These data suggest that both organic and aqueous fractions have good antioxidative compounds with different antioxidant properties.

• 동의생리병리학회지
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• 제27권4호
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• pp.422-430
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• 2013

This experiment was designed to investigate the effects of So-Oochim-tang-Gagam-bang (SOCT-G) on oxidative stress and serotonin metabolism in P815 Mast Cells The effects of SOCT-G on activity of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging and Super Oxide Dismutase (SOD) in P815 mast cells were investigated. The effect of SOCT-G on content of serotonin in P815 mast cells was investigated. The effects of SOCT-G on expression of 5-hydroxytryptamine transporter (5-HTT), Tryptophan hydroxylase 1 (TPH-1) mRNA in P815 mast cells were investigated. The SOCT-G increased DPPH radical-scavenging activity in P815 mast cells. The SOCT-G increased SOD activity in P815 mast cells. The SOCT-G decreased the intracellular content of serotonin in P815 mast cells. The SOCT-G decreased 5-HTT and TPH-1 mRNA expression in P815 mast cells. This experiment shows that So-Ochm-Tang-Gagam-bang has a significant effect of oxidative stress that help prevent free radical damage. And So-Ochim-Tang-Gagam-bang decreased the intracellular content of serotonin and mRNA expression of 5-HTT and TPH-1. Therefore, further researches are suggested to reveal the anti-depressive effectiveness of So-Ochim-Tang-Gagam-bang.

• Applied Biological Chemistry
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• 제38권6호
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• pp.590-595
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• 1995

냉이에탄올 추출물중의 항산화활성을 나타내는 물질의 특성을 조사하기 위해 각종 용매로 분획을 실시하여 헥산 분획(Fr.H), 에테르 분획(Fr.E), 에틸아세테이트 분획(Fr.EA), 부탄올 분획(Fr.B), 물 분획(Fr.D)의 5분획을 얻었다. 부탄을 분획은 가장 높은 수소공여능 및 과산화 지질 형성 억제 효과를 보인 반면, xanthine/xanthine oxidase-cytochrome c 환원 반응계에 의한 superoxide radical의 소거능에 있어서는 에테르 분획이 가장 높은 활성을 나타내었다. 또한 각 분획의 xanthine oxidase에 대한 저해효과를 측정한 결과 에테르분획이 가장 큰 저해 효과를 보였으며 $IC_{50}$값은 $5.65\;{\mu}g$이었다. 이러한 결과로 부터 에테르 분획의 높은 superoxide radical 소거능이 xanthine oxidase에 의한 라디칼 형성계에 대한 저해 활성으로 부터 기인한 것임을 알 수 있었다. 각 분획의 xanthine oxidase에 대한 저해 효과는 Fr.B

• 한국식품영양과학회지
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• 제34권9호
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• pp.1330-1335
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• 2005

붉은 갈색계통 염색제 성분 중의 하나인 p-phenylenediamine(PPD)는 일반적으로 여성들이 사용하는 염색제의 주요 성분으로 시야 흐림 및 구토와 같은 전신적 아나필락시스, 피부염 또는 방광암 등이 유발된다고 한다. 그러나 PPD의 피부 독성과 유해산소와 관련된 연구는 아직까지 미흡한 실정이다. 본 실험에서는 체중 $230\pm20g$의 Sprague-Dawley 종의 흰쥐의 피부에 PPD을 도포하였을 때 조직의 손상정도를 상호비교하고 조직의 손상 원인을 구명하고자 실험동물에 PPD($2.5\%$ PPD in $2\%\;NH_{4}OH$)을 표면적 $25 mg/16.5\;cm^2$씩 2일 간격으로 3회 및 5회 도포하였다. PPD 3회보다 5회 도포군에서 피부조직 의 표피 및 케라틴 층의 비후, glucose 5-phosphatase 활성의 감소 및 acid phosphatase 활성의 증가 정도가 높게 나타났다. 또한 유해산소의 생성계 및 해독계와 관련하여 피부조직의 손상정도를 확인한 결과, 유해산소 생성계인 xanthine oxidase의 활성은 PPD 3회 보다5회 도포군에서 유의하게 증가하였다. 그러나 유해산소 해독계인 superoxide dismutase, catalase, glutathione S-transferase 활성 및 reduced glutathione 함량은 대조군보다 PPD 도포군에서 감소하였다. 한편, xanthine oxidase의 활성이 3회 PPD 도포군에서는 별다른 변동이 없음에도 불구하고 oxygen free radical system의 감소와 피부조직의 손상이 나타난 것은 흰쥐의 피부조직 에서 PPD를 대사하는 동안 생성된 대사산물에 의한 것으로 생각된다. 이상의 실험 결과를 종합해 볼 때 PPD 도포에 의한 피부조직의 손상은 PPD 도포 횟수에 비례하여 유해산소 생성율이 증가하여 나타난 결과로 생각된다.

• 대한본초학회지
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• 제27권2호
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• pp.37-42
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• 2012

Objectives : The purpose of this study is to examine the antioxidant effects on male mouse reproductive cells of the extract of Platycladi Semen. Methods : The extract was studied for diphenyl-picryl-hydrazyl (DPPH) radical scavenging activity, cell viability by a modified MTT assay, the effects on $H_2O_2$-induced cytotoxicity by MTT assay, lipid peroxidation by malondialdehyde (MDA) formation and super oxide dismutase (SOD), respectively. Results : The results showed that the extract scavenged DPPH radical in a dose-dependent manner by up to 74.87%. The cell viability of the extract was within 72~96% on Leydig cells and GC-2 cells at concentrations of 1, 5, 10, 50 and 100 ug/ml. The hydrogen peroxide-induced cytotoxicity of Leydig cells was protected to 72.09% by the extract at concentration of 100 ${\mu}g/ml$. The hydrogen peroxide-induced lipid peroxidation of MDA formation was decreased to 1.80 and 1.65 nmoles/mg protein by the extract at concentrations of 50 and 100 ${\mu}g/ml$. The extract at all concentrations, SOD activity was not significantly changed. Conclusions : In conclusion, the extract of Platycladi Semen has antioxidant effects on Leydig cells and protect male reproductive system against oxidative stress.