• Title/Summary/Keyword: Oxidase

Search Result 2,540, Processing Time 0.036 seconds

Immobilization of Glucose Oxidase on Multi-Wall Carbon Nanotubes for Biofuel Cell Applications

  • JUNG SOO KEUN;CHAE YOUNG RAE;YOON JONG MOON;CHO BYUNG WON;RYU KEUN GARP
    • Journal of Microbiology and Biotechnology
    • /
    • v.15 no.2
    • /
    • pp.234-238
    • /
    • 2005
  • Glucose oxidase was immobilized on the carboxylated multi-wall carbon nanotubes (MWNT-COOHs) in the presence of a coulping reagent, 1-ethy1-3-(3-dimethylaminopropy1) carbodiimide. Significant amounts of glucose oxidase were also immobilized on MWNT-COOHs without the coupling reagent. Various conditions for the immobilization of glucose oxidase were optimized. Optimal pH for the maximal activity of the immobilized glucose oxidase shifted to 7 from the optimal pH of 6 for the maximal activity of free enzyme due to the carboxy1 groups on the surface of MWNT-COOHs. An electrode of graphite rod with a diameter of 6 mm was fabricated using the immobilized glucose oxidase. The cyclic voltammetry study of the enzyme electrode revealed that the oxidation of glucose and subsequent transfer of electrons from the oxidation of glucose to the electrode were possible by the immobilized glucose oxidase without a mediator, implying that the enzyme electrode can be utilized for the development of biofuel cells.

The Effect of Lidocaine and Procainamide on the Hepatic Aldehyde Oxidase Activity (알데히드 옥시다제의 활성에 미치는 리도카인 및 프로카인아미드의 영향)

  • Huh, Keun;Kim, Jin-Sook;Jin, Da-Qing;Ha, Eun-Pil;Lee, Sang-Il;Yong, Chul-Soon
    • YAKHAK HOEJI
    • /
    • v.43 no.6
    • /
    • pp.756-761
    • /
    • 1999
  • Lipid peroxidation mediated by hydroxyl radicals which are generated during myocardial ischermia has suggested as a possible mechanism of ischemic myocardial damage. Recently, it has been reported that anti-arrhythmic action of lidocaine, a local anesthetic, is attributed to its "membrane-stabilizing" properties through scavenging free radicals, thus, inhibiting lipid peroxidation. Aldehyde oxidase and xanthine oxidase which catalyze the oxidation of many purine, pyrimidine and pteridine derivatives are known as free radical generating systems. In this experiment, we studied the effect of lidocaine and procainamide on the hepatic aldehyde and xanthine oxidase activity and antioxidative activities. It was found that lidocaine and procainamide inhibited both NADPH-dependent and independent lipid peroxidation. Both of tested compounds were found to be ineffective in inhibiting xanthine oxidase. Lidocaine and procainamide, however, inhibited aldehyde oxidase activity in vitro as well as in vivo. Based on the above results, lidocaine and procainamide could be employed as a therapeutic agent for aldehyde oxidaserelated disease.d disease.

  • PDF

Screening of Anti-gout Xanthine Oxidase Inhibitor from Mushrooms (버섯류로부터 항통풍성 Xanthine oxidase 저해물질의 탐색)

  • Zanabaatar, Bolormaa;Song, Jung-Hwa;Seo, Geon-Sik;Noh, Hyung-Jun;Yoo, Young-Bok;Lee, Jong-Soo
    • The Korean Journal of Mycology
    • /
    • v.38 no.1
    • /
    • pp.85-87
    • /
    • 2010
  • Anti-gout xanthine oxidase inhibitory activity of water extracts from various mushrooms were determined. The highest xanthine oxidase inhibitory activity was 72.9% in the water extract from fruiting body of Agaricus brazillensis and also were high in the extract from fruiting bodies of Pleurotus salmoneostramineus(60.1%), Phellinus baumii(57.7%), Agaricus bisporus(56.7%) and Hericium erinaceum(53.4%). The xanthine oxidase inhibitor was maximally extracted when Agaricus brazillensis fruiting body was treated with water at $30^{\circ}C$ for 24 h.

Identification and characterization of cytochrome $bc_1$ complex and cytochrome c oxidase in chromatophore of rhodopseudomonas gelatinosa (Rhodopseudomonas gelatinosa의 chromatophore에서 시토크롬 $bc_1$ 복합체와 시토크롬 c 산화효소의 확인 및 특성연구)

  • 강대길;최명재;최원기
    • Korean Journal of Microbiology
    • /
    • v.29 no.4
    • /
    • pp.243-249
    • /
    • 1991
  • The chromatophore from the chemotrophically grown facultative anaerobic photosynthetic bacterium, Rhodopseudomonas gelatinosa ATCC 17013 was isolated through stepwise sucrose gradient centrifugation. The isolated chromatophore showed high activities of the cytochrome $bc_{1}$ complex and cytochrome c oxidase. The activity of cytochrome $bc_{1}$ complex was completely inhibited by .5$\mu$M antimycin A,10$\mu$M myxothiazol, and that of cytochrome c oxidase was completely inhibited by .$50\mu$M KCM and $100\mu$M $NaN_{3}$but not inhibited by carbon monoxie. The activity of cytochrome c oxidase of th chromatophore was increased by addition of ionophores or protonophores. The reduced-oxidised difference sspectrum of cytochrome $bc_{1}$ complex isolated by affivity chromatography showed the absorption maxima at 553 nm(shoulder at 547 nm), 520 nm, and 418.5 nm, on the other hand, that of cytochrome c oxidase showed .alpha., .betha. and soret peaks at 554 nm, 523 nm, and 421 nm, respectively. The cytochrome c oxidase from chemotrophically grown Rhodopseudomonas gelatinosa seems to be a b-type cytochrome c oxidase.

  • PDF

Physio-chemical studies on the seed-browning in mature green peppers stored at low-temperature (Part 2) -Changes in enzymatic activity with the seed-browning effect- (녹숙(綠熟)고추의 저온저장(低溫貯藏)에 따른 종자갈변(種子褐變)에 관(關)한 생리화학적연구(生理化學的硏究) -제 2 보(第 2 報) 종자갈변(種子褐變)에 따른 효소활성(酵素活性)의 변화(變化)-)

  • Lee, Sung-Woo
    • Korean Journal of Food Science and Technology
    • /
    • v.3 no.1
    • /
    • pp.37-43
    • /
    • 1971
  • (1) Relatively active polyphenol oxidase influence was seen at $0{\circ}C$, and the optimal pH level for the enzyme from the seeds of a small type sweet pepper Zairaisisi is 6.5. (2) The starting stage of the brown coloration with low-temperature injuries showed a strong activity of polyphenol oxidase, and the activity drops to 0 as the entire seed became brownish. (3) The browning effect with enzyme solution of polyphenol extracts suggested that the brown coloration continues in vitro even if polyphenol oxidase activity is nil. (4) Although cytochrome oxidase activity dropped when an abnormality occurrs in electron pathways of respiration at the starting stage of the browning with low temperature injuries, there was no marked influence of it on the total respiration, indicating the fact that polyphenol oxidase can take place of terminal oxidase in the compensatory respiration process.

  • PDF

Effects of Some Monoterpenes on Rat Brain Monoamine Oxidase (수종 모노테르펜계 화합물이 랫드 뇌의 monoamine oxidase활성에 미치는 영향)

  • 문창규;임종석;유충규
    • Journal of Food Hygiene and Safety
    • /
    • v.10 no.4
    • /
    • pp.279-282
    • /
    • 1995
  • Eight natural or semistynthesized monoterpenes were examined for their effects in rat brain monoamine oxidase(MAO) using benzylamine as substrate. Thujone and 3-carene were found to have the inhibition effects on rat brain MAQ activity, 38% and 95% inhibition at 103M respectively. The kinetic study on 3-carene, the most potent inhibitive type. But (+) pulegon and (-) isopulegon was found to activate MAO slightly.

  • PDF

Presence of an Inducible Semicarbazide-Sensitive Amine Oxidase in Mycobacterium sp. Strain JC1 DSM 3803 Grown on Benzylamine

  • Ro Young-Tae;Lee Hyun-Il;Kim Young-Min
    • Journal of Microbiology
    • /
    • v.44 no.2
    • /
    • pp.243-247
    • /
    • 2006
  • Mycobacterium sp. strain JC1 was capable of growth on benzylamine as a sole source of carbon and energy. The primary deamination of benzylamine was mediated by an inducible amine oxidase, which can also oxidize tyramine, histamine, and dopamine. Inhibitor study identified this enzyme as a copper-containing amine oxidase sensitive to semicarbazide.

Regulation of the Phagocyte Respiratory Burst Oxidase by Protein Interactions

  • Lambeth, J. David
    • BMB Reports
    • /
    • v.33 no.6
    • /
    • pp.427-439
    • /
    • 2000
  • The activity of the phagocyte respiratory burst oxidase is regulated by complex and dynamic alterations in protein-protein interactions that result in the rapid assembly of an active multicomponent NADPH oxidase enzyme on the plasma membrane. While the enzymatic activity has been studied for the past 20 years, the past decade has seen remarkable progress in our understanding of the enzyme and its activation at the molecular level. This article describes the current state of knowledge, and proposes a model for the mechanism by which protein-protein interactions regulate enzyme activity in this system.

  • PDF

EFFECT OF PANAX GINSENG ON XANTHINE OXIDASE ACTIVITY IN ETHANOL-INDUCED HYPERURICEMIA

  • Huh Keun;Choi Chong Won
    • Proceedings of the Ginseng society Conference
    • /
    • 1980.09a
    • /
    • pp.131-135
    • /
    • 1980
  • The influence of Panax ginseng on alcohol-induced hyperuricemia were observed. Changes of uric acid blood levels and hepatic xanthine oxidase activities were studied by means of treating alcohol intoxication with ginseng. It was found that a single dose (4 mg/Kg) of ginseng saponin administered intraperitoneally significantly inhibits the hepatic xanthine oxidase activities and decrease urate blood levels in ethanol-induced hyperuricemic mice. It was also observed that there were some difference in pharmacological aspect between Panax ginseng and allopurinol which is a potent inhibitor of xanthine oxidase from any sources.

  • PDF

The effect of L-Ascorbic Acid on the Oxidative Reaction of Lysine in Collagen. (Collagen 분자 중의 lysine 산화반응에 미치는 비타민 C의 영향)

  • 김미향
    • Journal of Life Science
    • /
    • v.14 no.3
    • /
    • pp.478-483
    • /
    • 2004
  • In a model reaction using lysyl oxidase purified partilally from bovine aorta, effect of L-ascorbic acid AsA on the oxidative reaction of lysine in collagen was investigated. Addition of Ash to the reaction mixture under aerobic conditions resulted in the decrease of enzymatic activity. In order to examine the specificity of AsA in the oxidative reaction of lysine, other reductants including A derivatives instead of AsA were added to the reaction mixture. Thiol such as glutathione had no effect on the activities of lysyl oxidase. on the other hand, it was observed that erythorbic acid, which was a stereoisomer of AsA, had the same inhibitory effect on this oxidative reaction as AsA. Moreover, by the addition of 3,4-dihydroxybenzoate, which was structural analog of AsA, the activities decreased in a similar manner to that of AsA. These results indicate that the regulatory effect of AsA on lysyl oxidase is attributed to characteristics of the structure. From the determination of Ash remained in the reaction mixture, it is shown that AsA concentration remarkably decreased by lysyl oxidase of the reaction mixture. It is hypothesized that endiol groups reduces the enzyme-bound $Cu^{+2}$ required for further progress of the reaction, and suggests that AsA regulates specifically the reduction of $Cu^{+2}$ required to oxidize lysyl oxidase. This findings support that AsA has an important regulatory role on the oxidative reaction of lysine and on changes of collagen cross-links with aging.