• Title/Summary/Keyword: Hydroxyl Radical

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Evidence for Singlet Oxygen Involvement in Cell-free Myeloperoxidase/$H_2O_2$/ Chloride Sytem: Exclusion of Hydroxyl Radical Involvement (Cell-free Myeloperoxidase/$H_2O_3$/Chloride System에서 Singlet Oxygen이 관여한다는 실험적 증거)

  • Chung Myung-Hee;Kim Yong-Sik
    • The Korean Journal of Pharmacology
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    • v.20 no.1 s.34
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    • pp.1-11
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    • 1984
  • The present study was performed to determine oxygen metabolites involved in cell-free MPO/$H_2O_2/Cl^-$ system by observing the effects of their scavengers on NADH oxidation and ethylene production from methional by the action of MPO prepared from human leukocytes. It was clearly demonstrated that NADH was oxidized by the cell-free MPO/$H_2O_2/Cl^-$ system as evidenced by complete inhibition of the oxidation of the substrate in the presence of eiher azide or catalase, or by omitting $Cl^-$. The MPO-mediated oxidation of NADH was completely abolished by a $^1O_2$ quencher, DABCO but not by $OH{\cdot}$ scavengers, mannitol, benzoate, formate and methanol. In ethylene assay, no ethylene was detected from methional in the MPO/$H_2O_2/Cl^-$ system with evident production of the gas by xanthine-oxidase and $Cu^{++}-H_2O_2$ systems which are suggested to generate $OH{\cdot}$. From the results obtained, it is concluded that $^1O_2$ is a major mediator with exclusion of $OH{\cdot}$ involvement in the cell-free MPO-mediated oxidation.

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Biological activity of water-soluble polysaccharides from Cedrela sinensis according to extraction methods (참죽의 추출방법에 따른 수용성 다당류의 생리기능성)

  • Oh, Min Hui;Hwang, Yeo Jin;Yoon, Kyung Young
    • Korean Journal of Food Science and Technology
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    • v.49 no.2
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    • pp.215-221
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    • 2017
  • The biological activity of water-soluble polysaccharide (WSP) fractions extracted from Cedrela sinensis was examined in this study. Cedrela sinensis was extracted using hot water, ultrasonication, and enzymes (Viscozyme, Shearzyme) and precipitated using ethanol to produce crude polysaccharides. The yield (3.51%) and total polysaccharide content (28.03 g/100 g) of WSP extracted using Shearzyme (WSPs) were highest compared to other extracts. The antioxidant activity of WSP extracted using hot water was highest and had the lowest $IC_{50}$ values in DPPH, ABTS, hydroxyl radical scavenging activity, reducing power, and superoxide dismutase-like activity. Tyrosinase inhibitory activity increased as the concentration increased. All extracts showed higher retardation effects on glucose and bile acid compared to the control; particularly, WSPs showed a similar glucose retardation effect to carboxymethyl cellulose. This study suggests that WSP from C. sinensis can be used as a functional food material.

Whitening and Antioxidant Effects of a Mixture of Poria cocas, Glycyrrhiza uralensis, and Ulmus macrocarpa Extracts (미백과 항산화에 미치는 백복령, 감초, 유백피 추출 혼합물의 영향)

  • Kwon, Eun-Jeong;Park, Hye-Jung;Nam, Hyang;Lee, Su-Gyeng;Hong, Su-Gyoung;Kim, Moon-Moo;Lee, Kyeong Rok;Hong, Il;Lee, Do Gyeong;Oh, Yunghee
    • Journal of Life Science
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    • v.24 no.10
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    • pp.1063-1069
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    • 2014
  • Reactive oxygen species (ROS) are known to lead to oxidation of lipids, proteins, and DNA and cause skin damage. Moreover, ROS promote melanogenesis, which causes melasma, age spots, and freckle. The main compounds of the herbal medicines Poria cocas, Glycyrrhiza uralensis, and Ulmus macrocarpa were reported to be parchymic acid, glabridin, and flavonoids, respectively. The aim of this study was to investigate the whitening and antioxidant effects of a mixture of P. cocas, G. uralensis, and U. macrocarpa extracts (PGUE) in B16F1 cells to develop whitening cosmetics. PGUE inhibited DPPH radicals and lipid peroxidation, in addition to high reduction power, compared with Glycyrrhiza uralensis ethylacetate extracts (GUEE). Furthermore, PGUE exhibited a protective effect against DNA oxidation induced by the hydroxyl radicals. In addition to its antioxidant activity, the inhibitory activity of PGUE against tyrosinase, which is associated with melanogenesis, was greater than that of arbutin used as a positive control. Moreover, PGUE exerted an inhibitory effect on melanin synthesis in live melanoma cells and reduced the expression levels of superoxide dismutase-1 (SOD-1) and tyrosinase related protein-1 (TRP-1). These results indicate that PGUE has skin whitening and antioxidant effects, suggesting that this mixture can be used as the main ingredient in the development of effective whitening cosmetics.

Effects of Shiryung-tang Extract on the Liver Injury induced by Ethanol in Rats (시령탕(柴苓湯)이 에탄올 투여로 유발된 흰쥐의 간손상에 미치는 방어효과)

  • Kim, Bum Hoi;Choi, Yung Hyun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.27 no.5
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    • pp.611-616
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    • 2013
  • Alcoholic liver disease (ALD) is a major cause of morbidity and mortality around the world. Although much progress has been made in understanding the pathogenesis of ALD, there remains no effective therapy for it. Accumulated evidence indicates that oxidative stress is the main pathological factors in the development of ALD. Ethanol administration causes accumulation of reactive oxygen species (ROS), including superoxide, hydroxyl radical, and hydrogen peroxide. ROS, in turn, cause lipid peroxidation of cellular membranes, and protein and DNA oxidation, which results in hepatocyte injury. In addition to pro-oxidants formation, antioxidants depletion caused by ethanol administration also results in oxidative stress. The objective of this study is to investigate the effects of Shiryung-tang extract on the chronic alcoholic liver injury induced by EtOH. Male Sprague Dawley rats were used in this study. All rats were maintained under standard laboratory conditions ($23{\pm}1^{\circ}C$, 12h light/12h dark cycles). All animals (n=30) were randomly divided into following groups: (1) Normal group, treated with distilled water (n=10); (2) Control group, treated with ethanol (n=10); (3) Sample group, treated with ethanol + pharmacopuncture (n=10). For oral administration of ethanol in Control and Sample group, the ethanol was dissolved in distilled water in concentrations of 25%(v/v). Throughout the experiment of 8 week, the rats were allowed free access to water and standard chow. Sample group were administrated by Shiryung-tang extract daily for 8 weeks. Control group were given normal saline for same weeks. As a results, the oral administration of ethanol for 8 weeks leads to hepatotoxicity. The levels of hepatic marker such as HDL-cholesterol, triglyceride, aspartate aminotransferase and alanine aminotransferase were altered. The ethanol also increased lipid peroxidation and depletion of antioxidant enzyme activities as well as hepatic tissue injury. However, the treatment of Shiryung-tang extract prevented all the alterations induced by ethanol and returned their levels to near normal. These data suggest that Shiryung-tang extract could have a beneficial effect in inhibiting the oxidative damage induced by chronic ethanol administration. Therefore, Shiryung-tang extract can be a candidate to protect against EtOH-induced liver injury.

Effects of Loquat (Eriobotrya japonica Lindl.) Ethanol Extracts of Different Aerial Parts on Antioxidant Activity and Antiproliferation of Human Cancer Cells (비파 부위별 에탄올 추출물의 항산화 활성 및 암세포 증식 억제효과)

  • Lee, Hwan;Kim, Yeon-Kyoung;Lee, Hyun-Joo;Lee, Jae-Joon
    • The Korean Journal of Community Living Science
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    • v.27 no.2
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    • pp.211-220
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    • 2016
  • The current study was carried out to determine the effects of the seed, flesh (seedless fruit), and leaf of loquat (Eriobotrya japonica Lindle.) on antioxidative activity and anti-proliferation in human cancer cells. Total polyphenol contents of loquat seed, flesh, and leaf ethanol extracts were found to be 17.77, 32.32, and 28.08 mg/g, respectively. Also, total flavonoid contents of loquat seed, flesh, and leaf ethanol extracts were found to be 18.77, 28.73, and 21.35 mg/g, respectively. The $IC_{50}$ values of DPPH hydroxyl scavenging of loquat seed, flesh, and leaf ethanol extracts were 0.049, 0.063, and 0.042 mg/mL, respectively. Antioxidative indexes of loquat leaf and seed ethanol extracts was highly and it was similar to the BHA and BHT. The antioxidative activities in loquat seed and leaf ethanol extracts were higher in loquat flesh. The antiproliferation effect of loquat seed and leaf ethanol extracts on liver cancer cell line (H460), stomach cancer cell line (AGS) and lung cancer cell line (A549) showed higher values compared with the flesh ethanol extracts. These results indicate that loquat ethanol extracts may play a positive role in antioxidative properties and cancer prevention.

Application of Electrochemical Technology for Reusing Biologically Treated Water (생물학적 처리수 재이용을 위한 전기화학 기술의 적용)

  • Kang, Gu-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.4
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    • pp.453-458
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    • 2008
  • Laboratory experiments were conducted to investigate disinfection as well as removal of color and residual organics from reclaimed municipal wastewater by electrochemical processes with Nb/Pt anode installed. RNO was rapidly bleached by OH$\cdot$ and the second order rate constants of RNO removal were $\frac{0.223l}{mg{\cdot}min}$, $\frac{1.679l}{mg{\cdot}min}$ and $\frac{2.322l}{mg{\cdot}min}$ with for 5 A, 10 A, and 15 A, respectively, with r$^2$ of > 96%. In batch electrochemical processes, after 15 min at currency of 15 A and initial pH of 5, 7,5 and 9, COD$_{Mn}$ was below 4 mg/L, color unit below 5 degree and general bacteria was not detected, the concentration of which are suitable for drinking water regulation. In the continuous electrochemical process, with HRT of 3.7$\sim$49.2 min, free chlorine were 0.2$\sim$0.7 mg/L, general bacteria was not detected, color unit below 5 degree and THMs was 0.017 mg/L. Therefore, electrochemical process with Nb/Pt anode was employed satisfactory to meet for reusing biologically treated water as well as disinfection.

Degradation of Humic Acid and Formation of Formaldehyde in PEROXONE Processes (PEROXONE(Ozone/Hydrogen Peroxide)공정에서의 부식산 분해 및 포름알데히드의 생성)

  • Kim, Kei Woul;Rhee, Dong Seok
    • Analytical Science and Technology
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    • v.14 no.1
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    • pp.80-87
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    • 2001
  • This research was studied the action of the coupling ozone-hydrogen peroxide on aqueous humic acid. PEROXONE process is enhanced the generation of hydroxyl radicals which is effective for degradation of organic matters. Therefore the changes of $UV_{254}$ and TOC were investigated through the change of concentrations, injection time of $H_2O_2$, initial pH of aqueous humic acid and concentrations of radical savenger as $HCO_3{^-}$ in the PEROXONE processes. And the GC/ECD was used to detect the formaldehyde formed by ozonation of humic acid. From the experimental results, concentrations and injection time of $H_2O_2$ and initial pH in solution in the PEROXONE processes were very important for enhancing the efficiency of degradation in humic acid. The results indicated that removal efficiency of TOC was the highest when concentration of $H_2O_2$ was 5mg/L, injection time of $H_2O_2$ was 5 minutes and initial pH in solution was 10.5. And presence of alkalinity in solution was reduced the efficiency of treatment. The formaldehyde were formed less PEROXONE processes than only ozone. When initial pH in solution were changed from 3.5 to 10.5, the formaldehyde were formed highest concentration at pH 5.

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Effects of Harmaline and Harmalol on the Oxidative Injuries of Hyaluronic Acid, Lipid and Collagen by $Fe^{2+}$ and $H_2O_2$ ($Fe^{2+}$$H_2O_2$에 의한 Hyaluronic Acid, Lipid와 Collagen의 산화성 손상에 나타내는 Harmaline과 Harmalol의 영향)

  • Cho, In-Sung;Shin, Yong-Kyoo;Lee, Chung-Soo
    • The Korean Journal of Pharmacology
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    • v.31 no.3
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    • pp.345-353
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    • 1995
  • ${\beta}-Carboline$ alkaloids including harmaline have been shown to inhibit enzymatically or nonenzymatically induced-lipid peroxidation of microsomes. This study was done to explore the antioxidant ability of harmaline and harmalol on the oxidative injuries of hyaluronic acid, lipid and collagen by $Fe^{2+}$ and $H_2O_2$. Their scavenging actions on reactive oxygen species were also examined. Harmaline, harmalol, superoxide dismutase, catalase and DMSO inhibited both degradation of hyaluronic acid by $Fe^{2+}$ and $H_2O_2$ and lipid peroxidation of microsomes by $Fe^{2+}$. In these reactions, DABCO inhibited degradation of hyaluronic acid but did not affect lipid peroxidation. ${\beta}-Carbolines$ inhibited degradation of cartilage collagen by $Fe^{2+}$, $H_2O_2$ and ascorbic acid. The reduction of ferricytochrome c due to autoxidation of $Fe^{2+}$, which is inhibited by superoxide dismutase, was not affected by harmaline and harmalol. They also did not have a decomposing action on $H_2O_2$. Hydroxyl radical production in the presence of $Fe^{2+}$ and $H_2O_2$ was inhibited by harmaline, harmalol and DMSO. Harmaline and harmalol may inhibit the oxidative injuries of hyaluronic acid, lipid and cartilage collagen by $Fe^{2+}$ and $H_2O_2$ through their scavenging actions on reactive oxygen species, OH and probably iron-oxygen complexes and exert antioxidant abilities.

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Curcumin Attenuates Hydrogen Peroxide Induced Oxidative Stress on Semen Characteristics during In Vitro Storage of Boar Semen

  • Jang, Hyun-Yong;Kim, Young-Han;Cheong, Hee-Tae;Kim, Jong-Taek;Park, In-Chul;Park, Choon-Keun;Yang, Boo-Keun
    • Reproductive and Developmental Biology
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    • v.33 no.2
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    • pp.99-105
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    • 2009
  • Curcumin is a major active component of the food flovour tumeric. It has been used for the treatment of many diseases such as inflammatory and infectious diseases, cancer and other disease due to its antioxidant properties. Curcumin is a powerful scavenger of many free radicals such as superoxide anion, hydroxyl radical and nitric oxide. The objective of this study was to investigate the antioxidative effects of curcumin against hydrogen peroxide on semen quality during in vitro storage of boar semen. The sperm treated with different concentration of curcumin (1, 5 and 10 ${\mu}M$) in the presence or absence of hydrogen peroxide (250 ${\mu}M\;H_2O_2$) were incubated for 3, 6 and 9 hr at $37^{\circ}C$ and analyzed sperm characteristics such as motility, membrane integrity (MI), lipid peroxidation (LPO), reactive oxygen species (ROS) and DNA fragmentation (DF). The sperm motility and MI in $H_2O_2$ treated group ($47.8%{\pm}6.8$ and $24.8%{\pm}2.2$) were significantly decreased when compare to curcumin treated group ($79.8%{\pm}2.7$ and $34.6%{\pm}1.0$, respectively) irrespective of incubation periods(p<0.05). The LPO of spermatozoal plasma membrane was measured by thiobarbituric acid (TBA) reactions for malondialdehyde (MDA), MDA level in control ($11.6{\pm}0.6\;nmol/L{\times}10^6$) and curcumin groups ($10.7{\pm}0.3\;nmol/L{\times}10^6$) were lower than those of curcumin plus $H_2O_2$ ($17.1{\pm}0.8\;nmol/L{\times}10^6$) or $H_2O_2$ group ($22.5{\pm}1.9\;nmol/L{\times}10^6$) from 3 to 9 hr incubation periods. The DF by sperm chromatin dispersion (SCD) test and ROS production measured by 2',7'-dichlorofluorescein (DCF) fluorescence intensity were no significantly difference through all experimental groups (p>0.05). Correlation among evaluation methods for sperm quality, motility vs MI and DF vs ROS was positively correlated while motility vs DF and ROS vs LPO were negatively correlated in all treatment groups. These results demonstrate that curcumin can effectively improve the sperm quality during in vitro storage of boar semen through its hydrogen peroxide scavenging mechanism as an antioxidant.

Antioxidant Enzyme Activity and Cell Membrane Stability of Korean Bermudagrass Genotypes Different in Ploidy at Dormant Stage (배수성이 다른 자생 버뮤다그래스의 휴면 전후 항산화 효소활성 및 세포막 안정성 변화)

  • Lee, Geung-Joo;Lee, Hye-Jung;Ma, Ki-Yoon;Jeon, Young-Ju;Kim, In-Kyung
    • Asian Journal of Turfgrass Science
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    • v.25 no.1
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    • pp.17-21
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    • 2011
  • Korean bennudagrass collections showed diverse genetic variations in their morphology, growth habit, and cytological aspects. Chromosome number and nuclear DNA content of the bennudagrasses indicated a ploidy level ranging from triploid (2n=3x) to hexaploid (2n=6x). In this study, we investigated the different responses of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, ascorbate peroxidase) and cell membrane stability of those bennudagrass cytotypes to lower temperature and shorter day length, which meets a dormant induction in Korea. All the antioxidant enzymes were found to be higher during dormant stage, while the heme-containing catalase which converts hydrogen peroxide ($H_2O_2$) to water and oxygen molecules was activated before dormant initiation in the three cytotypes except for hexaploid bennudagrass. The triploid and tetraploid which exhibited relatively finer leaves and a rapid establishment speed were found to show increased activities of superoxide dismutase and peroxidase enzyme. The malondialdehyde(MDA) which is a product of lipid peroxidation in the cell membrane damaged by the hydroxyl radical was increased in all cytotypes as temperature declined, and tri- and tetraploids which had more protective antioxidant enzymes demonstrated a significantly lower MDA production. Similarly electrolyte leakage was higher in penta- and hexaploidy, seemingly more damage to cell membrane when low temperature was implemented. Results indicated that antioxidant responses of different cytotypes were genetically specific, which needs to be investigated the relevance with the low temperature tolerance in the bermudagrass further at the molecular level.