• Title/Summary/Keyword: $^{\cdot}OH$ radical

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Effect of Pyroligneous Liquor on Oxygen Radicals and Their Scavenger Enzymes in Liver of CD Rats (흰쥐 간조직의 활성산소 및 제거효소에 미치는 목초액의 영향)

  • Choi, Jin-Ho;Cho, Weon-Ki
    • Journal of Nutrition and Health
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    • v.40 no.2
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    • pp.111-117
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    • 2007
  • This study was designed to investigate the effects of pyroligneous liquor on oxygen radicals and their scavenger enzymes in the liver of Cri/Bgi CD rats (7 rats per group). Male rats were fed a basic diet prepared in our Lab., PL-0 (Control), PL-1, PL-25, PL-50 and PL-75 groups were Prepared to be 0%, 1%, 25%, 50% and 75%with distilled water using pyroligneous liquor (35% of Choa Co. Ltd.), and were administrated orally for 8 weeks. Superoxide radical contents in liver mitochondria and microsomes were significantly decreased to 12-14%, 11-15%, respectively, in these PL-25 and PL-50groups compared with the control group. Hydroxyl radical content in mitochondria and microsomes were markedly decreased to 12-20% and 17%, respectively, in these PL-25 and PL-50% groups compared with the control group. Hydrogen peroxide content in mitochondria and microsomes were significantly decreased about 15-12% and 22-20% in liver of PL-25 and PL-50 groups compared with the control group. Mn-SOD and Cu/Zn-SOD activities in liver of PL-25 and PL-50 groups were remarkably increased to 15-25%, 11-16%, respectively, compared with the control group. GPx activities in mitochondria and microsomes were significantly increased in the liver of PL-25 and PL-50 groups compared with the control group. CAT activities in mitochondria and cytosol were significantly increased to 12-14%, 15-27%, respectively, in the liver of PL-25 and PL-50 groups compared with the control group. These results suggest that long term administration orally of 25 and 50% pyroligneous liquor may effectively inhibit the formation of oxygen free radicals, and also scavenger enzyme activities significantly increase through the administration orally.

Oxidative stress and the antioxidant enzyme system in the developing brain

  • Shim, So-Yeon;Kim, Han-Suk
    • Clinical and Experimental Pediatrics
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    • v.56 no.3
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    • pp.107-111
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    • 2013
  • Preterm infants are vulnerable to the oxidative stress due to the production of large amounts of free radicals, antioxidant system insufficiency, and immature oligodendroglial cells. Reactive oxygen species (ROS) play a pivotal role in the development of periventricular leukomalacia. The three most common ROS are superoxide ($O2^{\cdot-}$), hydroxyl radical ($OH^{\cdot}$), and hydrogen peroxide ($H_2O_2$). Under normal physiological conditions, a balance is maintained between the production of ROS and the capacity of the antioxidant enzyme system. However, if this balance breaks down, ROS can exert toxic effects. Superoxide dismutase, glutathione peroxidase, and catalase are considered the classical antioxidant enzymes. A recently discovered antioxidant enzyme family, peroxiredoxin (Prdx), is also an important scavenger of free radicals. Prdx1 expression is induced at birth, whereas Prdx2 is constitutively expressed, and Prdx6 expression is consistent with the classical antioxidant enzymes. Several antioxidant substances have been studied as potential therapeutic agents; however, further preclinical and clinical studies are required before allowing clinical application.

Characteristics of the sonolytic reaction of refractory aromatic compounds in aqueous solution by ultrasound (초음파에 의한 수중의 난분해성 방향족화합물의 반응특성)

  • Sohn, Jong-Ryueul;Mo, Se-Young
    • Journal of Korean Society on Water Environment
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    • v.18 no.4
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    • pp.411-419
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    • 2002
  • In this study, the series of ultrasonic irradiation for removal of refractory aromatic compounds has been selected as a model reaction in the batch reactor system in order to obtain the reaction kinetics. The products obtained from the ultrasonic irradiation were analysed by GC and GC/MSD. The decomposition of benzene produced toluene, phenol, and C1-C4 compounds, while the intermediates during the ultrasonic irradiation of 2,4-Dichlorophenol(DCP) were phenol, HCl, catechol, hydroquinone, and benzoquinone. It was found that more than 80% of benzene, and 2,4-DCP solutions were removed within 2 hours in all reaction conditions. The reaction order in the degradation of these three compounds was verified as pseudo-zero or first order. From the fore-mentioned results, it can be concluded that the refractory organic compounds could be removed by the ultrasonic irradiation with radicals, such as $H{\cdot}$ and $OH{\cdot}$ radical causing the high increase of pressure and temperature. Finally, it appeared that the technology using ultrasonic irradiation can be applied to the treatment of refractory compounds which are difficult to be decomposed by the conventional methods.

Antioxidative Activities of the Codonopsis lanceolata Extract in vitro and in vivo (더덕(Codonopsis lanceolata) 추출물의 in vitro 및 in vivo 항산화 효과)

  • Kim, Soo-Hyun;Chung, Mi-Ja;Jang, Hae-Dong;Ham, Seung-Shi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.2
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    • pp.193-202
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    • 2010
  • In vitro activities of Codonopsis lanceolata (CL) 70% ethanol extract and its fractions (hexane, chloroform, ethyl acetate, butanol and water) were examined by total polyphenol content, reducing power, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), 2,2-diphenyl-$\beta$-picrylhydrazyl (DPPH), and oxygen radical absorbance capacity (ORAC) assays. The ethyl acetate fraction from CL ethanol extract (CLEA) showed the highest total polyphenol content (22.7 mg/g) among five fractions, and also exhibited an excellent reducing power (0.42~1.27 at $250\sim1,000\;{\mu}g/mL$). CLEA at $100\sim400\;{\mu}g/mL$ concentrations had 27.7~70.3% of ABTS radical scavenging activity and the highest DPPH radical scavenging activity (81.6% at $400\;{\mu}g/mL$). CLEA had dominantly higher $ORAC_{{ROO}{\cdot}}$activity compared to other fractions. CLEA and butanol fraction had significantly higher $ORAC_{{OH}{\cdot}}$ activities than 70% ethanol extract, hexane, chloroform and water fractions. The CLEA exhibited the highest antioxidant activity in CL 70% ethanol extract and its fractions. Thus, effect of CLEA treatment on antioxidant gene expression under the oxidative stress conditions by a high fat diet in animal model was studied by microarray and RT-PCR methods. The 31 antioxidant genes were expressed but the genes were not up-regulated at least a two-fold by CLEA treatment. We concluded that CLEA does not have an indirect antioxidant effect but a direct antioxidant effect by up-regulation of antioxidant genes in high fat diet-induced obese mice.

Antimicrobial Agents and Applications on Polymeric Materials (고분자재료에 대한 항균성 물질과 적용)

  • Lee, Jae-Woong
    • Textile Coloration and Finishing
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    • v.20 no.3
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    • pp.39-56
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    • 2008
  • A wide variety of materials including aldehydes, cationic agents, alcohols, peroxygens, phenols and chlorinated phenols, metal ions are being employed as biocides. Among three levels for biocidal functions (sanitization, disinfection and sterilization), disinfection is an enough level for antimicrobial textiles. In terms of antimicrobial agents for textile applications, quaternary ammonium salts (QAS), chitosan, metal and metal salts, N-halamine based materials are developed with numerous research and the positive ions of those materials may result in disinfection of microorganisms. Photocatalysts, especially titanium dioxide (titania) produces the hydroxyl radical (${\cdot}\;OH$) which causes inactivation of microorganisms after UV radiation, have been used for antimicrobial applications.

FORMATION OF KETOACIDS AND AOC DURING OZONATION IN DRINKING WATER

  • Lee, Kyung-Hyuk
    • Environmental Engineering Research
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    • v.11 no.6
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    • pp.293-302
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    • 2006
  • The reaction of ozone with NOM (Natural Organic Matter) can occur by two different pathways: that involving molecular ozone and by way of reactions with hydroxyl radicals which are produced from the decomposition of molecular ozone. As such, the formation of ketoacids and Assimilable Organic Carbon (AOC) can be controlled by controlling the pathway by which ozone reacts with NOM. The ratios of $[OH{\cdot}]/[O_3]$ ($R_{CT}$ values) were determined under the various ozonation conditions. The $R_{CT}$ values increased with increasing initial ozone concentration. The $R_{CT}$ values (ranges from 10 to $35^{\circ}C$) increased linearly as temperature increased (within the range from 10 to $35^{\circ}C$). However, $R_{CT}$ was independent of hydraulic retention time (HRT). Operational conditions were found to affect the formation of AOC. The conditions where the molecular ozone reaction predominated resulted in an increase in the formation of AOC.

The Butanol Fraction of Bitter Melon (Momordica charantia) Scavenges Free Radicals and Attenuates Oxidative Stress

  • Kim, Hyun Young;Sin, Seung Mi;Lee, Sanghyun;Cho, Kye Man;Cho, Eun Ju
    • Preventive Nutrition and Food Science
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    • v.18 no.1
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    • pp.18-22
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    • 2013
  • To investigate radical scavenging effects and protective activities of bitter melon (Momordica charantia) against oxidative stress, in vitro and a cellular system using LLC-$PK_1$ renal epithelial cells were used in this study. The butanol (BuOH) fraction of bitter melon scavenged 63.4% and 87.1% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals at concentrations of 250 and $500{\mu}g/mL$, respectively. In addition, the BuOH fraction of bitter melon effectively scavenged hydroxyl radicals (${\cdot}OH$). At all concentrations tested, the scavenging activity of the BuOH fraction was more potent than that of the positive control, ascorbic acid. Furthermore, under the LLC-$PK_1$ cellular model, the cells showed a decline in viability and an increase in lipid peroxidation through oxidative stress induced by pyrogallol, a generator of superoxide anion ($O_2{^-}$). However, the BuOH fraction of bitter melon significantly and dose-dependently inhibited cytotoxicity. In addition, 3-morpholinosydnonimine (SIN-1), a generator of peroxynitrite ($ONOO^-$) formed by simultaneous releases of nitric oxide and $O_2{^-}$, caused cytotoxicity in the LLC-$PK_1$ cells while the BuOH fraction of bitter melon ameliorated oxidative damage induced by $ONOO^-$. These results indicate that BuOH fraction of bitter melon has protective activities against oxidative damage induced by free radicals.

Study of Antioxidation Action of Lenonuri herba Extract (익모초 추출물의 항산화 작용에 관한 연구)

  • Kim Jee Young;Lee Youn Hee;Kim Ju Yon;Roh Bo Kyung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.2 s.51
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    • pp.189-196
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    • 2005
  • Motherwort (Leonurus sibiricus L), a hemp nettle (Labiatae) plant, grows about 1.5${\~}$2 m high spontaneously to wildness in Korea, China, Japan, and other Asian place. Its medical applications includes women's uterine disease, urination, bloody stool, bloody urine, and hemorrhoids. It's also effective for high blood pressure, heart stimulation, and anti-cancer activity. We first prepared chlroform and methanol extracts of motherwort and then they were fractionated using water, $30\%$ methanol, $60\%$ methanol, and $100\%$ methanol, respectively. Each fractionates is assayed for free radical scavenging activities against DPPH and anti-oxidant activity by TBARS assay measuring lipid peroxidation using LDL. The $30\%$ and $60\%$ methanol fractionates of methanol extracts showed strong anti-oxidant activity compared to vitamin C. They also had more Potent SOD activity using pyrogallol at 250 ppm than that of vitamin C. These results suggest that anti-oxidant activities of motherwort may be applicable to development of natural anti-oxidant cosmetics. Possibility of nature anti-oxidation ability cosmetics is seen possibility low official.

6'-O-Galloylpaeoniflorin Protects Human Keratinocytes Against Oxidative Stress-Induced Cell Damage

  • Yao, Cheng Wen;Piao, Mei Jing;Kim, Ki Cheon;Zheng, Jian;Cha, Ji Won;Hyun, Jin Won
    • Biomolecules & Therapeutics
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    • v.21 no.5
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    • pp.349-357
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    • 2013
  • 6'-O-galloylpaeoniflorin (GPF) is a galloylated derivate of paeoniflorin and a key chemical constituent of the peony root, a perennial flowering plant that is widely used as an herbal medicine in East Asia. This study is the first investigation of the cytoprotective effects of GPF against hydrogen peroxide ($H_2O_2$)-induced cell injury and death in human HaCaT keratinocytes. GPF demonstrated a significant scavenging capacity against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, $H_2O_2$-generated intracellular reactive oxygen species (ROS), the superoxide anion radical ($O_2^-$), and the hydroxyl radical (${\cdot}$OH). GPF also safeguarded HaCaT keratinocytes against $H_2O_2$-provoked apoptotic cell death and attenuated oxidative macromolecular damage to DNA, lipids, and proteins. The compound exerted its cytoprotective actions in keratinocytes at least in part by decreasing the number of DNA strand breaks, the levels of 8-isoprostane (a stable end-product of lipid peroxidation), and the formation of carbonylated protein species. Taken together, these results indicate that GPF may be developed as a cytoprotector against ROS-mediated oxidative stress.

Oxidative Damage of DNA Induced by the Cytochrome c and Hydrogen Peroxide System

  • Kim, Nam-Hoon;Kang, Jung-Hoon
    • BMB Reports
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    • v.39 no.4
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    • pp.452-456
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    • 2006
  • To elaborate the peroxidase activity of cytochrome c in the generation of free radicals from $H_2O_2$, the mechanism of DNA cleavage mediated by the cytochrome c/$H_2O_2$ system was investigated. When plasmid DNA was incubated with cytochrome c and $H_2O_2$, the cleavage of DNA was proportional to the cytochrome c and $H_2O_2$ concentrations. Radical scavengers, such as azide, mannitol, and ethanol, significantly inhibited the cytochrome c/$H_2O_2$ system-mediated DNA cleavage. These results indicated that free radicals might participate in the DNA cleavage by the cytochrome c and $H_2O_2$ system. Incubation of cytochrome c with $H_2O_2$ resulted in a time-dependent release of iron ions from the cytochrome c molecule. During the incubation of deoxyribose with cytochrome c and $H_2O_2$, the damage to deoxyribose increased in a time-dependent manner, suggesting that the released iron ions may participate in a Fenton-like reaction to produce $\cdot$OH radicals that may cause the DNA cleavage. Evidence that the iron-specific chelator, desferoxamine (DFX), prevented the DNA cleavage induced by the cytochrome c/$H_2O_2$ system supports this mechanism. Thus we suggest that DNA cleavage is mediated via the generation of $\cdot$OH by a combination of the peroxidase reaction of cytochrome c and the Fenton-like reaction of free iron ions released from oxidatively damaged cytochrome c in the cytochrome c/$H_2O_2$ system.