• The Korean Journal of Ecology
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• v.17 no.3
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• pp.251-260
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• 1994

Nitrification potential bioassay and terpenoid analyses were performed to determine the roles of terpenoid as an inhibitor of nitrification in the Douglas fir (Pseudotsuga menziesii) forests. The effect of terpenoids in the forest floor was also tested by adding $10{\mu}g/ml$ of four terpenoids(${\alpha}-pinene,{\beta}-pinene,{\gamma}-terpinene, and terpinolene) to mineral soils. The amount of terpenoids in the litter was higher than that in the soil and varied over time, but the amount of terpenoids in the soils was relatively constant. The correlation between the amount of terpenoids in the litter and ammonium oxidation was in inverse proportion to that in the mineral layers $(r^2=0.678)$. Inhibition of ammonium oxidation by terpenoids in the litter was always higher than in the mineral layer, but nitrite oxidation was different from the ammonium oxidation. The fact that there was greater nitrate production from ammonium in the mineral layer than in the forest floor layer seems to be due to the less amounts of terpenoids in the mineral layer. The result of the experiment in which four terpenoids were added to the mineral layer suggests that, after some lag time, the four terpenoids were effective in inhibiting ammonium oxidation. However, nitrite oxidation did not appear to be affected by the four terpenoids. Accordingly, all of our results suggested that terpenoids in Douglas fir forests apparently would act as a part of the inhibitors of nitrification.

• Journal of Electrochemical Science and Technology
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• v.3 no.2
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• pp.85-89
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• 2012

This study demonstrates the direct anodic electrodeposition of polypyrrole (PPy), poly(3,4-ethyl-enedioxythiophene) (PEDOT), and polythiophene (PTh) on Cu electrodes by employing a corrosion inhibitor, succinonitrile (SN). SN was found to suppress anodic Cu dissolution beyond the oxidation potential of the polymer monomers. It is also revealed that the Cu surface passivated by SN is still adequately conductive to allow the redox reaction of 1,4-difluoro-2,5-dimethoxybenzene (FMB) and the oxidation of the polymer monomers. Through both cyclic voltammetry and galvanostatic techniques, PPy, PEDOT, and PTh films were successfully synthesized on Cu electrodes in the presence of SN, and the redox behaviors of the films were evaluated.

• Journal of the Korean Applied Science and Technology
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• v.27 no.4
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• pp.531-538
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• 2010

The electrochemistry characterization of metal is important in many industrial applications. In this study, we investigated the C-V diagrams related to the electrochemistry characterization of nickel. We determined electrochemical measurement by using cyclic voltammetry with a three electrode system. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650mV and measured to the initial point. The scan rate were 100, 150, 200 and 200mV/s. As a result, the C-V characterization of nickel using ethanolamine and ethylethanolamine inhibitor appeared irreversible process caused by the oxidation current from the cyclic voltammogram. After adding ethanolamine compound additive, adsorption film constituted, and the passive phenomena happened. According to the results by cyclic voltammetry method, it was revealed that the effect of the electrochemistry characterization of nickel depends on ethanolamine structure interaction to adsorption complex.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.146.1-146.1
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• 2003

A major protein was isolated from ginseng root (Panax ginseng C.A. Meyer) using a combination of ammonium sulfate fractionation, gel filtration chromatography, ion-exchange FPLC. Electrophoretic and gel permeation chromatographic studies revealed that the major protein, GMP, is composed of two subunits of approximately 28 kDa. In this, investigated the ability of GMP to inhibit the oxidation of low-density lipoprotein (LDL). GMP inhibited $Cu^{2+}$ (5$\mu$M)-promoted oxidation of LDL (125$\mu$g protein/mL) in a dose-dependent mamer (0~5 $\mu$M), with a maximal inhibitor at GMP/copper ratio of 1:10 and an $IC_{50}$ value of 0.2 $\mu$M, as determined by measurement TBARS. (omitted)

• The Korean Journal of Pharmacology
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• v.20 no.1 s.34
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• pp.47-54
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• 1984

Effect of ascorbic acid on various hepatic ethanol metabolizing enzymes including alcohol dehydrogenase(ADH), the microsomal . ethanol oxidizing system(MEOS), and catalase was quantitatively evaluated in liver microsomal and cytosolic preparation from Sprague-Dowley rats. In present study, ADH activities were no changed significantly by ascorbic acid. The MEOS activity, dependent on NADPH and $O_2$, was affected by azide (inhibitor of catalase) or exogenous catalase. In the presence of ascorbic acid, ethanol oxidation by rat liver microsomal preparation reacted with NADPH-generating system was increased by up to 22.5%, but decreased when liver microsome was reacted with $H_2O_2$ generated by xanthine and xanthine oxidase. Increase in the activity of the MEOS in the presence of ascorbic acid was greater in liver microsomal preparation pretreated with azide. Also ascorbic acid oxidized ethanol nonenzymatically. This ethanol oxidation induced by ascorbic acid was inhibited by OH radical scavengers (thiourea, sodium benzoate), but was not much affected by superoxide dismutase. From these results it was suggested that ascorbic acidcould interact directly with the MEOS, then promote the oxidation of ethanol. And, to some extent, ${\cdot}OH$-radicals or other radicals generated during the spontaneous autooxidation of ascorbic acid may be responsible for the production of acetaldehyde from ethanol.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.375-380
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• 2002

In this study, newly designed COX-2 inhibitors, synthetic derivatives of benzothiazine-3-carboxamide, were screened in vitro for selectivity of COX-1 and COX-2 inhibition properties. 7-Bromo-1,2-benzoisothiazine derivatives were obtained from 4-bromotoluene over the chlorosulfonation, amination and oxidation. And benzothiazine ring was synthesized through Gabriel-Colmann rearrangement reaction. To evaluate inhibitory effect of COX-2, synthetic derivatives of benzothiazine-3-carboxamide were tested with accumulation of prostaglandin by lipopolysaccharide in aspirin-treated murine macropharge cell. Some of the synthesized lead compounds have potentially shown the structure-activity relationship for selectivity of COX-2 inhibition activity.

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.150-150
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• 2005

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2005.05a
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• pp.151-151
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• 2005

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.181.2-181.2
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• 2003

Inosine monophosphate dehydrogenase(IMPDH) catalyzes the $NAD^+$-dependent oxidation of IMP to XMP, the rate limiting step in the de novo biosynthesis of guanine nucleotide. Its critical role at the metabolic branch point in purine nucleotide biosynthesis makes it a useful target in the development of drugs for antiviral and anticancer chemotherapy and in immunosupressant area. Several compound with antiviral activity have been found to be inhibitors of IMPDH. For example, ribavirin, a competitive inhibitor of IMPDH, has broad spectrum antiviral activities against DNA and RNA viruses. (omitted)

• Korean Journal of Microbiology
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• v.32 no.4
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• pp.252-257
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• 1994

A new hydrogen sulfide-oxidation bacterium, Thiobacillus sp. was isolated from waste coal mine water around Hawsun in Chunnam province. The isolate was motile gram-negative rod shape, formed spore and grew up to be aerobically facultative chemolithotroph by using energy released from the oxidation of reduced inorganic sulfur compounds. It could assimilate various kinds of organic compounds and grew well upon thiosulfate-supplemented basal medium. To the lelvel of 32 mM in thiosulfate concentration, thiosulfate in itself was utilized as energy source for growth. However, from those of the higher concentration than 32 mM, thiosulfate functioned specifically as the substrate inhibitor rather than as the energy source. It was found that the optimum thiosulfate concentration for growth was 32 mM. The G+C content of the DNA was 65.0 mol%. The isolate had 16 : 1 + 17$_{cyc}$, 16 : 0 as their major non-hydroxylated cellular fatty acids, 3-OH 12 : 0 as a hydroxylated fatty acid and also contained unidentified $C_{18}$ branched fatty acid. The ubiquinone system in the respiratory chain was Q-9. Based on the physiological and biochemical characteristics, the isolate was assigned to a novel species of the genus Thiobacillus sp. iw.