• Title/Summary/Keyword: OH.라디칼

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Flavonoid and Phenol Contents and Antioxidant Effect of Wine By-product Extracts (포도주 부산물의 총 플라보노이드와 총 페놀 함량 및 항산화 효과)

  • Baek, Jae Yeol;Lim, Sun-Young
    • Journal of Life Science
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    • v.26 no.8
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    • pp.948-954
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    • 2016
  • We investigated the flavonoid and phenol contents and antioxidant effect of wine by-product extract. Antioxidant effects were measured with 1,1-diphenyl-2-picryhydrazyl (DPPH) and 2.2'-azino-bis(3-ethylbenothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS+) assays. Cellular reactive oxygen species (ROS) were measured with the dichlorofluorescein-diacetate (DCFH-DA) assay. The flavonoid and phenol contents of the methanol (MeOH) extract were greater than those of the acetone+methylene chloride (A+M) extract. Among fractions, the 85% aqueous methanol (85% aq. MeOH) fraction contained the highest flavonoid contents, while the n-BuOH fraction had more phenol contents. In the DPPH and ABTS assays, the MeOH extract showed a scavenging effect greater than that of the A+M extract (p<0.05). The n-BuOH fraction (0.5 mg/ml concentrations) showed scavenging effects of 72% and 92%, respectively, in the DPPH and ABTS assays (p<0.05). However, the 85% aq. MeOH fraction showed a 90% scavenging effect in the DPPH assay only. In 120 min ROS production assay, all tested fractions dose-dependently decreased cellular ROS production induced by H2O2 in comparison with that produced by exposure to the extract-free control. The MeOH extract showed a higher sinhibitory effect on cellular ROS producing than that of the A+M extract at all concentrations tested. Treatment with the n-BuOH fraction (0.1 mg/ml concentrations) inhibited cellular ROS production by 60%. These results indicate that the n-BuOH fraction of wine by-product extract inhibited cellular oxidation and may contain valuable bioactive compounds such as flavonoids and phenols.

Free Radical Scavenging, Cytotoxic Effects, and Flavonoid Content of Fractions from Leaves of Lycopus lucidus Turcz. (택란 잎 추출물의 라디칼 소거활성과 세포독성효과 및 플라보노이드 함량)

  • Na, Eun;Lee, Jung Woo;Lim, Sun Young
    • Journal of Life Science
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    • v.29 no.3
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    • pp.337-344
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    • 2019
  • The free radical scavenging, cytotoxic effects, and flavonoid content of fractions from Lycopus lucidus Turcz leaves were here investigated. The flavonoid contents of 85% methanol (MeOH) and n-butanol (BuOH) fractions of the leaves were 41.5 mg/g and 77.2 mg/g, respectively. In DPPH and ABTs+ assays, 85% MeOH and n-BuOH fractions from the L. lucidus Turcz leaves had a greater scavenging effect (p<0.05). The n-BuOH fraction (0.5 mg/ml concentration) had scavenging effects of 88% and 92% in the DPPH and ABTs+ assays, respectively (p<0.05). Cell viability tests showed that treatment with L. lucidus Turcz leaf fractions caused cytotoxicity in the growth of AGS, HT-29, and HT-1080 cancer cells. Of the different fractions, the 85% MeOH sample displayed the highest cytotoxic activity; the $IC_{50}$ values of this fraction against AGS, HT-1080, and HT-29 cancer cells were 0.03 mg/ml, 0.14 mg/ml, and 0.16 mg/ml, respectively. These biological results indicate that the n-BuOH fraction was more effective in anti-oxidant activity while the 85% MeOH fraction was stronger in cytotoxic effects, and they suggest that these two fractions from L. lucidus Turcz leaves may contain valuable bioactive compounds, such as flavonoids.

The Contribution of OH radical and the Effect of Adding Oxidants on the Sonolytic Degradation of 1,4-Dioxane (초음파를 이용한 1,4-Dioxane의 처리에서 OH 라디칼의 기여와 산화제 첨가의 효과)

  • Son, Hyun-Seok;Choi, Seok-Bong;Khan, Eakalak;Zoh, Kyung-Duk
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.6
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    • pp.642-650
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    • 2005
  • This research investigates the effects of adding oxidants such as $Fe^0$, $Fe^{2+}$, and ${S_2O_8}^{2-}$ in the sonolysis of 1,4-D. Results indicate that the degradation could be divided into two steps (initiation and acceleration) kinetically. The initial portion agreed with zero-order expression, while the second portion could be fitted with pseudo first-order expression. In the presence of ${HCO_3}^-$, as a radical scavenger, the degradations of 1,4-D and TOC were suppressed, indicating that OH radical is an important factor in the sonolysis. The overall degradation efficiency of 79.0% in the sonolysis was achieved within 200 minutes. While $Fe^0$, $Fe^{2+}$, and ${S_2O_8}^{2-}$ were individually combined with sonication, the degradation efficiency of 1,4-D increased 18.6%, 19.1%, and 16.5% after 200 min, respectively. The addition of oxidants not only changed the kinetic model from zero to pseudo first order at initiation step, but also increased the rate constants in the acceleration step. The addition of oxidants in the sonolysis of 1,4-D also improved the mineralization of 1,4-D, however, the effect of adding oxidants on the rate increase was similar regardless of the oxidants.

A Study on the Characteristics of Sonication Combined with UV in the Degradation of Phenol (초음파와 UV에 의한 페놀 분해 특성에 관한 연구)

  • Kim, Seong-Keun;Son, Hyun-Seok;Im, Jong-Kwon;Khim, Jee-Hyeong;Zoh, Kyung-Duk
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.7
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    • pp.649-655
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    • 2010
  • This study investigated the degradation of phenol using sonication and/or UV-C. The effects of frequency, temperature, pH in solution, argon purging, with UV intensity were estimated in sonication-only, UV-only, and the combined reaction of sonication with UV. The optimum condition for degrading phenol in the sonication-only reaction was 35 kHz, $5^{\circ}C$, and pH 4. As this condition approximately 30% degradation of phenol was achieved within 360 min. However, phenol in the UV-only at $19.3\;mw/cm^2$ under the same condition was completely degraded within 60 min. In the combined system of sonication with UV, the degradation of phenol was well fitted to first-order rate model, and phenol was completely degraded within 360 min and 45 min at UV intensity of $7.6\;mW/cm^2$($17.3{\times}10^{-3}\;min^{-1}$) and $19.3\;mW/cm^2$($138.1{\times}10^{-3}\;min^{-1}$), respectively. Adding methanol, as a radical scavenger, in the phenol degradation in the sonication reaction indicates that OH radical is a major factor in the degradation of phenol. The order of degradation efficiencies of phenol was in the order of as follows; combined reaction of sonication with UV > UV-only > sonication-only.

Comparative Study of the Antioxidant Activity Effects of Gami-Sumiwon Extract using Water and 80% Ethanol (가미수미원의 열수 추출물과 80% 에탄올 추출물의 항산화 효능 비교)

  • Lim, Hyun-Ji
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.5
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    • pp.1302-1313
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    • 2021
  • In this study, Gami-Sumiwon (GS; Cynanchi wilfordii R., Angelica gigantis R., Lycium chinense M., Betula platyphylla S., Cryptotympana atrata F. and Carthamus tinctorius L.) and/or Sinomenium acutum R. (SC) was extracted with 70% ethanol or water. And We investigated the antioxidant activity effect of GS±SC. The following experimental techniques were used to evaluate the antioxidant efficacy of GS±SC. HPLC chromatogram, heavy metal content, ABTS/DPPH radical scavenging analysis, SOD-like activity assay, FACS, and NO assay. As a result of the experiment, the sinomenine content was found to be higher in DW extracts, and decursin was found to be higher in 80% ethanol extracts. And, the amount of heavy metals in all extracts was below the standard value. ABTS, and DPPH radical scavenging activity was identified that GS±SC(EtOH) was found to have a higher scavenging activity than GS±SC(DW). But, SOD showed the opposite result. No cytotoxicity of GS was observed on Raw 264.7 cells at concentration of 1~100 ㎍/㎖. The ROS production was significantly decreased that GS±SC(DW) was found to have a higher scavenging activity than GS±SC(EtOH). However, NO production showed the opposite result. Looking at the results of SOD and ROS analysis, SC does not seem to have a function of prevention. SC is thought to have an effect on the removal of free radicals generated after oxidative stress. This result objectively confirmed the antioxidant effect of GS±SCs. We will continue to conduct in-depth research. Therefore, it is believed that the possibility of using GS±SCs as a functional material can be established. The more diverse the objectives, the higher the value of GS utilization is thought to be.

Isolation and identification of lignans as Antioxidant from loaves of Catalpa ovata G. $D_{ON}$ (개오동나무 잎으로부터 항산화 활성을 갖는 lignan 화합물의 분리 및 동정)

  • 국주희;마승진;문제학;박근형
    • KSBB Journal
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    • v.18 no.6
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    • pp.511-516
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    • 2003
  • The methanol extract from leaves of Catalpa ovata 6. DoN showed DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging activity, and its antioxidative compounds were studied. The ethyl acetate-soluble neutral fraction from the methanol extract was successively purified with silica gel adsorption column chromatography, Sephadex LH-20 column chromatography and HPLC. Three antioxidative compounds were isolated and identified as piperitol, pinoresinol and lariciresinol by HR-MS and NMR spectroscopic analyses. The DPPH radical-scavenging activity of the identified compounds decreased in the order of lariciresinol > pinoresinol > piperitol.

Removing Malodor Using Photocatalyst and Infrared (광촉매와 적외선을 이용한 악취저감)

  • Jeon, Tae-Yeong;Kim, Jae-Yong
    • Journal of Korean Society of Environmental Engineers
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    • v.36 no.8
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    • pp.528-533
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    • 2014
  • Recently, people interest in environmental pollution and attempt to improve the indoor air quality contaminated with various pollutants since it is very important to construct healthy and comfortable living environment. In the current study, we used the technology that has first received the certification of green technology for improving the removal efficiency of malodor causing substances. This green technology is a new technology to increase the reactivity of the odorous substances with OH radicals for oxidation reaction by using an infrared lamp in the existing air purification system. Comparing the efficiency of the green technology with the infrared lamp to that of the existing technology of air cleaner, there was a difference in the decomposition efficiency depending on the initial concentrations and speciation of the odorous substances. The removal efficiencies of contaminants were enhanced by 16.9 and 13.2% at low and high concentrations, respectively.

Characteristics of Chemiluminescence Intensities of Kerosene/Air Swirl Flames (케로신/공기 와류 화염의 화학발광 세기 특성에 관한 실험적 연구)

  • Lee, Hyeonjae;Seo, Seonghyeon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.6
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    • pp.485-496
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    • 2015
  • The present study presents experimental results on the characteristics of emission spectra of kerosene/air swirl flames. The aviation fuel Jet A-1, which is used for the liquid rocket engines of the Korea Space Launch Vehicle, is used with three different swirlers to investigate the swirl strength effects. The emission spectra from the flames are measured with a spectrometer as the swirl strength and combustion air temperature are varied. Chemiluminescence intensities of $OH^*$, $CH^*$ and $C_2{^*}$ are identified from the spectra. The chemiluminescence intensities from the kerosene flames show sensitivity to the swirl strength and are affected by changes in the combustion air temperature. Among the three radicals of interest, $C_2{^*}$ show the most significant changes in chemiluminescence intensity with the swirl strength and equivalence ratio. The intensity ratios $I_{OH^*}/I_{CH^*}$ and $I_{C_2{^*}}/I_{CH^*}$ are adequate for indicating changes in the equivalence ratio with the air and fuel mass flow rates, respectively.

Study on optical emission spectroscopic method for measuring OH radical distribution in rocket plume (로켓 플룸 내부 OH 라디칼 공간분포 계측을 위한 발광 분광 기법에 관한 연구)

  • Han, Kiwook;Hahn, Jae W.
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.1135-1139
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    • 2017
  • Spatial distribution of chemical species in flame is a important indicator understanding the flame structure and combustion characteristics, and optical emission spectroscopy has been widely used for the measurement because of its simple and non-intrusive methodology. In this study, we suggest the feasibility of the measurement of chemical species (OH radical) distribution in rocket plume using optical emission spectrometer which was developed for the spatially resolved measurement along the line-of-sight. In order to predict the ground state concentration of species from the measured emission intensity by optical emission spectrometer, we consider thermal and chemical excitation mechanisms in flame, and assume thermodynamic equilibrium for the thermally excited species. We also present the spatial resolution and the correction of collection characteristics of the optical emission spectrometer depending on object distance.

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Effects of the Recess and Propellants Mass Flow on the Flammability Limit and Structure of Methane-Oxygen Diffusion Flame (인젝터 리세스와 추진제 공급유량이 메탄-산소 확산화염의 가연한계와 구조에 미치는 영향)

  • Hong, Joon Yeol;Bae, Seong Hun;Kim, Jeong Soo
    • Journal of the Korean Society of Propulsion Engineers
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    • v.22 no.1
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    • pp.28-35
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    • 2018
  • In order to analyze the flammability limit and structure of the gaseous methane-gaseous oxygen diffusion flame formed through a shear coaxial injector, combustion experiments were carried out according to the condition of injector recess and propellant mass-flow rate. As a result, it was confirmed that stable anchored flame was observed even at the high oxygen Reynolds number as the propellant momentum flux ratio increased, and that the recess had no significant influence on the flame shape and flammability limit. The anchored flame visualized through a chemiluminescence showed the maximum OH radical emission intensity at a specific position, irrespective of the propellant injection condition, and the radical intensity was greatly reduced by the injector recess.