• Title/Summary/Keyword: superoxide anion radical

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Examination of the Nickel Site Structure in Streptomyces seoulensis Superoxide Dismutase by EPR and X-ray Absorption Spectroscopy

  • Lee, Jin-Won;Yim, Yang-In;Michael J. Maroney;Kang, Sa-Ouk
    • Proceedings of the Korean Biophysical Society Conference
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    • 1998.06a
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    • pp.26-26
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    • 1998
  • Superoxide dismutases are metalloenzymes catalyzing the dimutation of superoxide anion radical to hydrogen peroxide and molecular oxygen. Examples of enzymes containing Cu, Mn and Fe as the redox-active metal have been characterized. Recently, an SOD containing one Ni atom per subunit was reported.(omitted)

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Screening of antioxidant and antimicrobial activities of Caesalpinia bonducella Flem., leaves (Caesalpiniaceae)

  • Gupta, Malaya;Mazumdar, UK;Kumar, Ramanathan Sambath;Gomathi, Periyasamy;Rajeshwar, Y.;Kumar, T. Siva
    • Advances in Traditional Medicine
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    • v.4 no.3
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    • pp.197-209
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    • 2004
  • The study was aimed at evaluating the antioxidant and antimicrobial activities of methanol extract of Caesalpinia bonducella leaves (MECB) (Family: Caesalpiniaceae). The effect of MECB on antioxidant activity, reducing power, free radical scavenging (DPPH radical, nitric oxide radical, superoxide anion radical, hydroxyl radical and hydrogen peroxide radical scavenging), total phenolic content and antimicrobial activities were studied. The antioxidant activity of MECB increased in a dose dependent manner. About 50, 100, 250 and 500 g of MECB showed 53.4, 61.2, 69.1 and 76.2 % inhibition respectively on peroxidation of linoleic acid emulsion. Like antioxidant activity, the effect of MECB on reducing power increased in a dose dependent manner. The free radical scavenging activity of MECB was determined by DPPH radical scavenging method. The potency of this activity was increased with increased amount of extract. MECB was found to inhibit the nitric oxide radicals generated from sodium nitroprusside $(IC_{50}\;=\;102.8\;g/ml)$ whereas the $IC_{50}$ value of curcumin was 20.4 g/ml. Moreover, the MECB was found to scavenge the superoxide generated by photoreduction of Riboflavin. MECB was also found to inhibit the hydroxyl radical generated by Fenton reaction, where the $IC_{50}$ value is 104.17 g/ml compared with catechin 5 g/ml, which indicates the antioxidant activity of MECB. The MECB capable of scavenging hydrogen peroxide in a concentration-dependent manner. The amounts of total phenolic compounds were also determined. Antimicrobial activities of MECB were carried out using disc diffusion methods with five Gram positive, four Gram negative and four fungal species. The results obtained in the present study indicate that MECB leaves are potential source of natural antioxidant and antimicrobial agents.

The Changes in the Chemical Components and Antioxidant Activities in Ecklonia Cava According to the Drying Methods (건조방법에 따른 해조류(감태)의 주요성분 및 항산화 활성의 변화)

  • 김진아;이종미
    • Journal of the Korean Home Economics Association
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    • v.42 no.5
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    • pp.193-203
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    • 2004
  • This study examined the changes in the chemical components and antioxidant activity of Ecklonia cava according to the drying methods. As chemical components, the concentrations of minerals(K, Ca, Na, Mg, Fe, Cu, Mn and Zn), vitamins(vitamin C, ${\beta}$-carotene and ${\alpha}$-tocopherol) and the total polyphenols were analyzed. In additions, the antioxidant activity was determined by measuring the free radical(DPPH radical, superoxide anion radical, hydroxyl radical and hydrogen peroxide) scavenging activity and the linoleic acid peroxidation inhibitory activity. The mineral content was not affected by the drying methods. However, more vitamins were lost and the total polyphenol concentration was reduced as a result of sun-drying than by the other drying methods used. More of the total polyphenol was preserved by freezing-drying than by any of the other drying methods, which meant that there was a higher antioxidant activity after freeze drying.

Studies on the Anti-inflammatory Activity of Paulownia coreana Uyeki Leaf Extract (오동나무 잎 추출물의 항염 효능에 관한 연구)

  • Kim, Nam-Kyoung;Kim, Mi-Hwa;Yoon, Chang-Soon;Choi, Shin-Wook
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.32 no.4 s.59
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    • pp.241-247
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    • 2006
  • This work was carried out to investigate the anti-inflammatory effects of Paulownia coreana Uyeki on abirritant, atopy and acne skin. Paulownia coreana Uyeki has been used as a traditional medicine having anti-febrile, anti-inflammation effect in Korea, Paulownia coreana Uyeki loaves were extracted with 70% EtOH. Its superoxide anion radical scavenging activity and inhibitory effect on LPS-induced NO production were examined. The extract inhibitied the generation of NO and $PGE_2$ induced by LPS in the macrophage cell line (Raw 264.7). Consistent with the inhibitory effects on No and $PGE_2$ generation, the extract inhibited expression of iNOS and COX-2. In further study, it was found that the extract prevented $IkB-{\alpha}$ degradation, as demonstrated by western blot analysis of $IkB-{\alpha}$ protein level. However, the extract treatment did not affect cell viability at $100{\mu}g/mL$ concentration in both human skin fibroblast and Raw 264.7 cells in vitro. Thus, the present study suggests that Paulownia coreana Uyeki leaves extract have significant anti-inflammatory activity and potential as an anti-irritation material.

Antioxidant Activity and Radioprotection of Two Flavonoids from Propolis (프로폴리스에서 분리한 플라보노이드 화합물의 항산화 활성 및 방사선 방어효과)

  • Jeong, Ill-Yun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.2
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    • pp.162-166
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    • 2005
  • Two flavonoids, 7-O-methyl-3',4'-didehydroxy quercetin (MDQ) and quercetin, isolated from Chinese propolis, which is the generic name for the resinous substance collected by honeybees from various plant sources, were tested for their antioxidant activity and protective effect against radiation-induced DNA damage in mouse lymphocytes. In antioxidant test, both compounds provided a dose-dependent scavenging effect on DPPH radical and a dose-dependent inhibitory effect on lipid peroxidation in mouse liver. Quercetin showed stronger scavenging and inhibitory effect than MDQ, and it also provided strong inhibition on superoxide anion radical generated in xanthine-xanthine oxidase system, but there was no inhibitory ability for MDQ. In comet assay using single cell gel electrophoresis, MDQ and quercetin showed a protective effect against DNA damage caused by gamma irradiation. They reduced DNA damage to 54% (p<0.01) and 53% (p<0.01) at 25 $\mu$mol, respectively. These results suggest that free radical scavenging seems to be associated with their catechol form on the B ring, and radioprotection appears to be a likely mechanism of antioxidant activity by these flavonoids.

Antioxidant and anti-inflammatory effects of phenolic rich Hylotelephium erythrostictum extracts (폴리페놀 함량이 높은 Hylotelephium erythrosticum 추출물의 항산화 및 항염 활성)

  • Kim, Sang Suk;Park, Kyung Jin;Lee, Seung Eun;Lee, Jeong Hoon;Choi, Young Hun
    • Food Science and Preservation
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    • v.24 no.6
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    • pp.842-848
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    • 2017
  • Hylotelephium erythrostictum is commonly used as a medicinal herb. In this study, H. erythrostictum leaf (HEL), branch (HEB), root (HER), and above ground (HEAG) extracts were evaluated for their antioxidant properties. The antioxidant activities were assayed by three methods based on scavenging of DPPH, ABTS and superoxide anion radical. HEAG extract showed the highest DPPH, ABTS, superoxide anion radical scavenging activities. HEAG extract also exhibited the highest phenolic content (230 mg/g gallic acid equivalent). In our research for anti-inflammatory ingredients, the extract of HEAG inhibited the generation of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. To test the inhibitory effects of HEAG on pro-inflammatory cytokines, we conducted ELISA assay for the measuring the generation of tumor necrosis factor $(TNF)-{\alpha}$, IL (interleukin)-$1{\beta}$, and IL(interleukin)-6 in LPS-stimulated RAW264.7 macrophage cells. In these assays, HEAG ethanol extract showed a dose-dependent decrease in the production of $TNF-{\alpha}$, $IL-1{\beta}$, and IL-6. Based on these results, extract of HEAG could be the efficient candidate for anti-inflammatory agents.

Studies on Immunomodulatory and Antioxidant Activities of Astragali membranacei Radix according to the Cultivated Years (황기(黃芪)의 재배 년수에 따른 면역 및 항산화 활성 연구)

  • Jung, Chul
    • Korean Journal of Korean Medical Institute of Dermatology and Aesthetics
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    • v.1 no.1
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    • pp.53-90
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    • 2005
  • Purpose: Contents of astragaloside I, II and IV, cytotoxicity, anticancer activity, immunomodulatory activity and antioxidant capacity were to be compared as a function of the cultivated years as one, three, five and seven years. Method: Major components of Astragali membranacei Radix were separated as astragaloside I, astragaloside II, astragaloside IV by HPLC analysis. Cytotoxicity and anticancer activities were measured by MTT and SRB assay. For immunomodulatory activity, the secretion of IL -6 and $TNF-{\alpha}$, NK cell activation and macrophage activation were observed as well as kinetics of responding to human T cells by a microphysiometer. In vitro antioxidant activities were measured by several radical scavenging activities of superoxide anion radican, DPPH, LDL and linoleic acid. For in vivo activity, the activation of SOD, GSH-px, catalase, ALDH and ADH was measured as well the relative weight of liver. Result : 1. For HPLC analysis, the contents of all of astragaloside I, astragaloside II, astragaloside IV were in order of three, five, one and seven years. 2. The cytotoxicity of normal human lung cell line, HEL299 showed lower than 18% in adding 0.25 mg/ml, and 28.9% in adding 1.0 mg/ml of water extract of seven year root. For methanol extracts, three year root showed highest cytotoxicity as 35.2 % and there was no difference between the cultivated years. 3. For anticancer activities, methanol extracts of one and three year roots showed relatively high inhibition of human stomach cancer cells, AGS, breast cancer cells, MCF-7, lung cancer cells, A549 and liver cancer cell, Hep3B as well as high selectivities. 4. The water extract of seven year root could yield high secretion of IL-6 from both human Band T cells while the methanol extracts of three and five year roots secreted high amounts of IL-6 and $TNF-{\alpha}$ from both Band T cells. 5. As a result of in vitro antioxidant activities, both water and methanol extracts from five and seven year roots showed high activities for superoxide anion radical scavenging activity, inhibiting linoleic acid peroxide and contents of total phenols. 6. For in vivo tests, Mn-SOD and GSH-px activities and weight of liver were better in adding seven year root. For ALDH activity one year root was better and for ADH activity five year root. Overall speaking, seven year root showed relatively better antioxidant activities. Conclusion:There was difference of the contents of astragaloside I, astragaloside II, astragaloside IV according to cultivation year. Methanol extract showed better activities of anticancer and immune activation rather than water extract Interestingly enough, for methanol extracts, overall activities were improved as the cultivation year increased. There might be further investigation required for the clinical uses of the results as several biological activities varied according to the cultivated year of Astragali membranacei Radix.

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Antioxidant and Inhibitory Activities on Angiotensin Converting Enzyme in Lysimachia clethroides Duby (큰까치수영의 항산화 및 안지오텐신 전환 효소 저해 활성)

  • Bang, Jin-Ki;Seong, Nak-Sul;Lee, Seung-Eun
    • Applied Biological Chemistry
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    • v.47 no.2
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    • pp.265-269
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    • 2004
  • This study was conducted to develop physiologically active plant materials from medicinal plants. Crude extracts and solvent fractions prepared from Lysimachia cletroides Duby were tested for their antioxidant and antihypertensive activities. For ellucidating antioxidant potential, inhibition rate on linoleic acid peroxidation, as well as scavenging activities on superoxide anion and 1,1-dipicrylphenylhydrazyl (DPPH) radical were evaluated. For analyzing antihypertensive effect, inhibitory activity on angiotensin converting enzyme (ACE) was done. Methanol extract of L. cletroides showed potent inhibition activity of 83% on linoleic acid peroxidation, which was more effective than -2% of ${\alpha}-tocopherol$ at $25\;{\mu}g/ml$. Methanol and water extracts exhibited strong scavenging activities of $86{\sim}109%$ and $96{\sim}122%$ on superoxide anion radical which was higher than $-4{\sim}69%$ of ascorbic acid at $5{\sim}200\;{\mu}g/ml$. Hexane, ether and ethylacetate fractions possessed 133, 100 and 88% inhibitory activities on ACE at $4,000\;{\mu}g/ml$, respectively. From the results, it was expected that Lysimachia cletroides could be a new antioxidant and antihypertensive resource.

A Study of Effects of Crataegus pinnatifida var. psilosa Extracts (좁은잎산사나무 열매 추출물의 효능에 관한 연구)

  • Lee, Kwang-Soo;Park, Kyung-Sook
    • The Korean Journal of Food And Nutrition
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    • v.31 no.6
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    • pp.775-782
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    • 2018
  • The purpose of this study was to investigate effects of Crataegus pinnatifida var. psilosa extracts obtained from 95% methanol and water. Methylene chloride, ethyl acetate, and methanol were used to fractionate the 95% methanol extract and each fraction was testified total polyphenol contents, electron donating abilities, the scavenging abilities of superoxide anion radical, as well as hydrogen peroxide. Extraction yields of 95% methanol and water from Crataegus pinnatifida var. psilosa were 25.40%, 23.12% respectively. Total polyphenol contents were $28,708.0{\pm}1,755.05{\mu}g\;GAE/mL$ in 95% methanol, revealing the highest among them, $12,726.67{\pm}479.33{\mu}g\;GAE/mL$ in water extract, $15,854.67{\pm}498.38{\mu}g\;GAE/mL$ in methanol fraction, $11,810.67{\pm}584.48{\mu}g\;GAE/mL$ in ethyl acetate fraction, and $5294.67{\pm}190.36{\mu}g\;GAE/mL$ in methylene chloride fraction. Total polyphenol contents revealed significant differences (p<0.05) between the solvents. In the experiment of the electron donating ability, water extract revealed $84.33{\pm}0.1%$ scavenging ability, the highest. Other extracts and fractions were $81.8{\pm}1.11%$ for water, $79.73{\pm}1.32%$ for ethyl acetate fraction, $75.73{\pm}2.17%$ for methylene chloride fraction, and $42.1{\pm}5.01%$ for methanol fraction, the lowest electron donating ability. Electron donating abilities revealed significant difference (p<0.05) between the solvents. In the experiment of superoxide anion radical scavenging ability, ethyl acetate fraction($0.0026{\pm}0.0002$) had the highest scavenging ability, and the others revealed slight increase rather than decrease in scavenging ability. Hydrogen peroxide scavenging ability revealed the highest in methanol fraction ($-0.00206{\pm}0.00165$) and the others were as follow; water extract ($0.00157{\pm}0.00249$), 95.0% methanol extract ($0.005{\pm}0.0036$), methylene chloride fraction ($0.0039{\pm}0.00364$), and ethyl acetate fraction ($0.0002{\pm}0.00059$).

Screening on Radical Scavenging Activity of Salt Marsh Plants (염생식물로부터 천연항산화 활성소재 탐색)

  • Kim, You-Ah;Lee, Hee-Jung;Seo, Young-Wan
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.673-675
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    • 2003
  • The antioxidant activities of methanol and dichloromethane extracts of eighteen salt marsh plants were tested by using 1,1-Diphenyl-2-picryl-hydrazyl(DPPH) at a $100{\mu}g/ml$ concentrations. The methanol extracts of four salt marsh plants(Rosa rugosa Thunberg, Erigeron annuus, Ixeris tamagawaensis kitamura, Artemisia capillaris Thunberg) were found to be most effective in DPPH radical scavenging activity. The DPPH radical scavenging effect of these plants was Artemisia capillaris Thunberg(88.67%), Rosa rugosa Thunberg(87.51%), Erigeron annuus(78.49%), Ixeris tamagawaensis kitamura(69.99%) in order and was comparable with that of natural antioxidant, L-ascorbic acid(96.64%). The next effective ones were the methanol extracts of Teragonia tetragonoides(58.66%) and the dichloromethane extracts of Artemisia capillaris Thunberg(54.67%) and the others did not show a considerable activity. These salt marsh plants were evaluated using the pyrogallol UV-VIS spectrophotometeric method to generate superoxide anion. Among them, the dichloromethane extracts of four salt marsh plants and the methanol extracts of fifteen ones were weak superoxide dismutase-like activities.

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