• Title/Summary/Keyword: 자동산화반응

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Kinetic Study on the Autoxidation of Methyl Linolenate by NMR Spectrometer (NMR에 의(依)한 Methyl Linolenate의 자동산화속도측정(自動酸化速度測定))

  • Ahn, Jong-Kyoon;Kwon, Tae-Bong;Cho, Mi-Za;Kim, Soo-Il;Oh, Sung-Ki
    • Applied Biological Chemistry
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    • v.32 no.1
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    • pp.8-13
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    • 1989
  • The rate constant and reaction order of the autoxidation of methyl linolenate were determined by using nuclear magnetic resonance spectrometer, and the applicability of nmr to the kinetic study was examined. The autoxidation was carried out under a mild condition, i.e., the air flow rate of 90m1/min and room temperature. The autoxidation of methyl linolenate followed the first-order kinetics, and the rate constant was found to be $1.96{\times}10^{-2}hr^{-1}$.

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Formation of Superoxide Anion in the Autoxidation of L-Ascorbic Acid in the Presence of Heavy Metal Ions (중금속 이온 존재하에서의 아스코르빈산 자동산화 과정에서 $O_2\bar{{\bullet}}$ 생성)

  • Kim, Mi-Ok
    • Korean Journal of Food Science and Technology
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    • v.33 no.3
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    • pp.378-383
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    • 2001
  • Formation of superoxide anion $O_2\bar{{\bullet}}$ in the autoxidation of L-ascorbic acid (AsA) in the presence of heavy metal ions were determined. The generation of $O_2\bar{{\bullet}}$ was studied by using superoxide dismutase (SOD) in aqueous and buffer solution, and using nitro bule tetrazolium (NBT) in methanol solution. The remaining amount of AsA was significantly higher in the presence of SOD than in its absence. It suggested that SOD stabilizes AsA in aqueous and buffer solution because of scavenging $O_2\bar{{\bullet}}$ formed during the autoxidation reaction of AsA in the presence of heavy metal ions. NBT has an absorption maximum at about 560 nm in methanol solution. The absorbance at 560 nm increased during the oxidation of AsA, suggested the formation of $O_2\bar{{\bullet}}$in methanol solution. Thus, the formation of $O_2\bar{{\bullet}}$ was confirmed during the autoxidation of AsA not only in aqueous solution but also in methanol solution in the presence heavy metal ions.

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윤활 오일에서 재가 생기지 않는 산화방지제, 구리 반응 억제제와 부식 방지제의 이용에 관한 고찰

  • 강석춘
    • Tribology and Lubricants
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    • v.6 no.2
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    • pp.1-15
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    • 1990
  • 본 해설에서는 윤활 오일에서 구리 반응 억제제와 철의 부식 억제제에 관한 내용을 검토한 것으로 자동산화 화정의 초기 생성과 연쇄적인 전파, 확산 및 종료 그리고 1차 및 2차 산화 억제제에 관해서 서술한 것이다. 구리 반응 억제제와 부식 억제 성질 및 작용이 고려되고 첨가제로써의 응용에 관해 조사하였다.

Oxidation Characteristics of Biodiesel and Its Blend Fuel I (바이오디젤 및 바이오디젤 혼합 연료의 산화 특성 I)

  • Jung, Chung-Sub;Dong, Jong-In
    • Applied Chemistry for Engineering
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    • v.18 no.3
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    • pp.284-290
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    • 2007
  • Biodiesel and its blend fuels from soybean oil were characterized for their oxidation to apply automobile fuel from the analysis of FAME (fatty acid methyl ester) and chemical properties. Biodiesel produced from soybean oil contained unsaturated fatty acids (> 85 wt%) such as oleic acid, linoleic acid, and linolenic acid. Especially, polyunsaturated fatty acids such as linoleic acid and linolenic acid containing active methyl radical were over 60 wt%. It is believed that linoleic acid and linolenic acid cause oxidation. Linoleic acid and linolenic acid during oxidation were major reactants, and compounds with the carbon number having around 36 (boiling point of about $500^{\circ}C$) were produced from those of radical autoxidation.

Effects of Water Activity and Light on the Oxidation of Carrot Carotenoids (당근 카로티노이드의 자동산화에 미치는 수분활성도 및 광선의 영향)

  • Song, Eun-Seung;Kim, Hae-Gyoung;Song, Yeong-Ok;Jeon, Yeong-Soo;Cheieh, Hong-Sik
    • Korean Journal of Food Science and Technology
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    • v.25 no.6
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    • pp.775-779
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    • 1993
  • The effects of water activity and light on the oxidation of carotenoid were studied using both the model systems of carrot lipids and freeze dried carrot. Autoxidation of crude lipids from the freeze dried carrot and the stability of carotenoids in controlled systems varing water activities and/or lights were examined. The degree of autoxidation of crude lipid stored at $30^{\circ}C$ for 16 days was significant(p< 0.05) and 71.8% destruction of carotenoid in the crude lipids were observed. When the powdered solid models of freeze dried carrot were stored at $30^{\circ}C$ for 35 days under various water activities and the presence of light, the maximum stability of carotenoid was found at $a_{w}$ 0.42 and the damaging effect of lights on the stability of carotenoid was significant (p<0.05). The absoprtion spectra of carotenoids changed according to the degree of oxidation, but shifts of the maximum wavelength was not observed.

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Effects of Various Proteins on the Autoxidation of L-Ascorbic Acid (비타민 C 산화반응에 대한 단백질의 공존효과)

  • Kim Mi-Ok;Jang Sang-Moon
    • The Korean Journal of Food And Nutrition
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    • v.17 no.3
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    • pp.294-301
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    • 2004
  • Effects of superoxide dismutase(SOD), catalase(CAT), and such other proteins as bovine serum albumin(BSA), ovalbumin, lysozyme, and v-globulin on the autoxidation rates of L-ascorbic acid(AsA) in the absence of heavy metal ions and in the presence of Fe(III) or Cu(II) ions in water were examined. AsA was dissolved in a ultra-refined water at a concentration of 50 ${\mu}$M and 5 ${\mu}$M Fe(III) or 0.1 ${\mu}$M Cu(II) were added, and a oxygen gas was bubbled through the solution at a flow rate of 200 ml/min at 35$^{\circ}C$. The amount of remaining AsA in the reaction mixture was determined by using a UV spectrophotometer(at 265 nm). It was found that the Cu(II) at a concentration of 0.1 ${\mu}$M had a more accelerated for the autoxidation of AsA than Fe(III) at 5 ${\mu}$M. Moreover, it was confirmed that the ratio of remaining AsA was significantly larger in the presence of SOD, CAT, BSA, ovalbumin, lysozyme, and v-globulin than in the absence of proteins. The stabilization of AsA by various proteins were confirmed during the autoxidation of AsA in the presence of Fe(III) or Cu(II) in water. It was suggested that the non-enzymatic effects of SOD, CAT and some other proteins might be involves in the stabilization of AsA.

Development of the Blood Glucose Strip for the Detection of Glucose in Blood (혈당 측정용 스트립 개발에 관한 연구)

  • 송은영;김경아;이홍수;권두한;남효진;김희정;변시명;정태화
    • Biomedical Science Letters
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    • v.4 no.2
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    • pp.103-112
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    • 1998
  • We have developed a simple and accurate strip test that measures the blood glucose level semiquantitatively by visual observation, or qualitatively by using UltraScan spectrocolorimeter. The strip has solid phase reagents, including glucose oxidase, peroxidase, chromogen, affixed to a plastic support. The strip test is capable of measuring blood glucose level in the range of 0∼800 mg/dl and generating the results within 2 to 3 minutes. Human blood specimens obtained from normal individuals and the diabetic patients were evaluated by the new blood glucose strip and by the kit supplied by other commercial products. The test results exhibit the correlation coefficient of 0.964. The new test strip is proven simple and accurate, and it offers an alternative to the commercially available glucose tests.

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Function of the Water Soluble Browning Reaction Products Isolated from Korean Red Ginseng 2. Linoleic acid, Ox-brain autoxidant and Fe$^{2+}$ ADP/NAD system (홍삼으로부터 분리한 수용성 갈변물질의 기능성 연구 2. Linoleic acid, Ox-brain autoxidant및 Fe$^{2+}$ ADP/NADP system에서 항산화 활성 중심으로)

  • 이종원;손형옥;도재호
    • Journal of Ginseng Research
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    • v.24 no.1
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    • pp.35-40
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    • 2000
  • The purpose of this study was to investigate the antioxidant activities of water soluble browning reaction products (WS-BRPs) isolated 5\ulcorneron korea red ginseng. Antioxidant activities of WS-BRPs were examined with the various systems. All three WS-BRPs (L, S-1 and S-2) were found to have an ability to linoleic acid, Ox-brain autoxidant, Fe$^{2+}$ ADP/NAD system and cumene hydroperoxide system. Especially, S-2 was had the strongest activity of theses three WS-BRPs to scavenge free radicals such as more effective than S-1, L. MDA determination showed the antioxidant effect on linoleic acid oxidation inhibition ratio of 22.5%, 31.7%, 31.9% and 33.5%, respectivity Especially; Ox-brain autoxidant was strong inhibited activity by 49.52%,62,44,97.54% by addition of various concentration. But three WS-BRPs showed weak inhibitory activity on lipid peroxidation in rat hepatic microsomes induced enzymatically and nonenzymaticallyly

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