• Korean Journal of Pharmacognosy
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• v.45 no.2
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• pp.93-100
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• 2014

The Acer tegmentosum (3 kg) were extracted with boiled water and the freeze dried extract powder was partitioned with $CH_2Cl_2$, EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc and n-BuOH fraction, six phenolic compounds were isolated through the silica gel, octadecyl silica gel and sephadex LH-20 column chromatography. On the basis of spectroscopic methods, such as $^1H$-NMR and $^{13}C$-NMR, and LC/MS, the chemical structures of the compounds as feniculin (1), avicularin (2), (+)-catechin (3), (-)-epicatechin (4), salidroside (5) and 6'-O-galloylsalidroside (6). In this study, compounds 1 and 2 have been first isolated from the A. tegmentosum. To provide insight into the effects of six compounds isolated from A. tegmentosum on inflammation, we investigated its effect on nitric oxide (NO) production in RAW 264.7 cells using lipopolysaccharide (LPS) stimulation. Compounds 1 and 6 slightly repressed NO production. Also, compounds 3 and 4 inhibited NO secretion with statistical significance. However, compounds 2 and 5 did not show any inhibitory effect on NO production.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.84-89
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• 2001

Isolation and Characterization of Cathepsin B inhibitor Produced by Streptomyces luteogriseus KT-IO. Han, Kil~Hwan and Sang~Dal Kim*. Department of Applied Microbiology, Yeungnam Universit}/t Kyongsan 712749, Korea - The cathepsin B inhibitor produced by Streptomyces luteogriseus KT-IO was very stable in heat, acidic and alkaline conditions. The cathepsin B inhibitor was isolated from the extracted fraction of culture broth with butanol, methanol and chloroform subsequently, the inhibitor was purified with following several column chromatography sLlch as DEAE-Sephadex A-25, Sephadex G-15, silica gel 60, Sephadex LH-20, and preparative HPLC. The cathepsin B inhibitor showed positively to detective reaction of ninhydrine, 5% H2S04, iodine, but negatively to the reaction of Ehrlich's reagent, DNS, aniline. The molecular formular of cathepsin B inhibitor was elucidated by JR, lH and 13C-NMR, FAB mass and elemental analyzer. Consequently, it was identified as C4HlI04N6. The cathepsin B inhibitor had the mode of competitive inhibition with the reaction of cathepsin B.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.8
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• pp.597-601
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• 2013

The accelerated thermal aging of a CSPE were carried out for 0, 80.82, 161.63 days at $100^{\circ}C$, which are equal to 0, 40 and 80 years of aging at $50^{\circ}C$, respectively. The volume electrical resistivities of the seawater and freshwater flooding were measured through 3-terminal circuit diagram. The volume electrical resistivities of the 0y, 40y and 80y were $2.454{\times}10^{13}{\sim}1.377{\times}10^{14}{\Omega}{\cdot}cm$, $1.121{\times}10^{13}{\sim}7.529{\times}10^{13}{\Omega}{\cdot}cm$ and $1.284{\times}10^{13}{\sim}8.974{\times}10^{13}{\Omega}{\cdot}cm$ at room temperature, respectively. The dielectric constant of the 0y, 40y and 80y were 2.922~3.431, 2.613~3.285 and 2.921~3.332 at room temperature, respectively. It is certain that the ionic ($Na^+$, $Cl^-$, $Mg^{2+}$, ${SO_4}^{2-}$, $Ca^{2+}$, $K^+$) conduction current was formed by the salinity of the seawater. The volume electrical resistivity of the cleaned CSPE via freshwater trends slightly upward with the number of dried days at room temperature. As a result, the $CH_2$ component of thermally accelerated aged CSPE decreased after seawater and freshwater flooding for 5 days respectively, whereas the atoms such as Cl, O, Pb, Al, Si, Sb, S related with the conducting ion ($Na^+$, $Cl^-$, $Mg^{2+}$, ${SO_4}^{2-}$, $Ca^{2+}$, $K^+$) component increased relatively.

• The Korean Journal of Physiology
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• v.24 no.1
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• pp.39-49
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• 1990

It has been reported that bombesin induces contraction of the smooth muscle of the gastrointestinal tract. Thus, the present investigation was undertaken to see an influence of bombesin on electrical activity of the gastric smooth muscle, since electrical activity is associated with contractile activity in the smooth muscle of the stomach. Smooth muscle strips $(5\;{\times}\;1.5\;cm)$ that included the corpus and antrum were prepared from the ventral and dorsal portion of the feline stomach along the greater curvature. Circular muscle strips $(1\;{\times}\;0.3\;cm)$ of the corpus were also obtained. Electrical activity of the corpus and antrum of the muscle strip was monophasically recorded by using Ag-AgCl capillary electrodes placed on the circular muscle layer. Contractile activity of the circular muscle strip was also recorded. The recordings were performed in Krebs-Ringer solution that was continuously aerated with $O_{2}$ containing 5% $Co_{2}$, and kept at $36^{\circ}C$. Dose-related responses of electrical activity and contractility to bombesin was studied after frequency of slow waves and contraction of each strip reached to a steady state. An action of $D-leu^{13}-{\psi}\;(CH_{2}NH)-D-leu^{14}-bombesin,\;D-pro^{2}-D-trp^{7,9}-substance\;P$, tetrodotoxin, hexamethonium, atropine, phentolamine or propranolol on the effect of bombesin was also observed. 1) Bombesin increased frequency of slow waves and contractions dose-dependently at concentrations from $10^{-9}\;M\;to\;3\;{\times}\;10^{-8}\;M$. 2) The bombesin analogue at a concentration of $3\;{\times}\;10^{-7}\;M$ antagonized the effect of bombesin on frequency of slow waves. 3) The effect of bombesin on frequency of slow waves was inhibited by tetrodotoxin $(10^{-6}\;M)$ and hexamethonium $(10^{-3}\;M)$ but unaffected by atropine $(10^{-6}\;M)$, phentolamine $(10^{-5}\;M)$ and propranolol $(10^{-5}\;M)$. 4) The effect of bombesin on frequency of slow waves was blocked by the substance P analogue at a concentration of $10^{-5}\;M$. 5) Substance P at a concentration of $10^{-5}\;M$ failed to change frequency of slow waves. It is concluded from the above results that bombesin increases the frequency of slow waves as well as contractions of the smooth muscle strip from the feline stomach, and the effect of bombesin might be mediated by non-cholinergic or non-adrenergic mechanism at neuromuscular junction. However, enteric nerves that have substance P as a neurotransmitter do not appear to participate in the action of bombesin on frequency of slow waves.

• Applied Biological Chemistry
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• v.17 no.2
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• pp.125-137
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• 1974

The chemical structure of glycolipid of Selenomonas ruminantium cell wall was to be elucidated. The bacterial cells were treated in hot TCA and the glycolipid fractions were extracted by the solvent $CHCl_3\;:\;CH_3OH$ (1 : 3). The extracted glycolipids fraction was further separated by acetone extraction. The acetone soluble fraction was named as the spot A-compound. The acetone insoluble but ether soluble fraction was named as the spot B-compound. These two compounds were examined for elucidation of their chemical structure. The results were as follows: 1. The IR spectral analysis showed that O-acyl and N-acyl fatty acids were linked to glucosamine moiety in the spot A-compound. However in the spot B-compound in addition to O and N-acyl acids phosphorus was shown to be attached to glucosamine. 2. It was recognized by gas liquid chromatography that spot A compound contained beta-OH $C_{13:0}$ fatty acid in predominance in addition to the fatty acid with beta-OH $C_{9:0}$, whereas the spot B compound was composed of the predominant fatty acid of beta-OH $C_{13:0}$ with small amount of beta-OH $C_{9:0}$. 3. According to the paper chromatographic analysis of hydrazinolysis products of the spot A compound, a compound of a similar Rf value as the chitobiose was recognized, which indicated a structure of two molecules glucosamine condensed. The low Rf value of the hydrazinolysis product of the spot B-compound confirmed the presence of phosphorus attached to glucosamine. 4. The appearance of arabinose resulting from. ninhydrin decomposition of the acid hydrolyzate of the spot A compound indicated that the amino group is attached to $C_2$ of glucosamine. 5. The amount of glucosamine in the N-acetylated spot A compound decreased in half of the original content by the treatment. with $NaBH_4$, indicating that there are two molecules of glucosamines in the spot A compound. The presence of 1, 6-linkage between two molecules of glucosamine was suggested by the Morgan-Elson reaction and confirmed by the periodate decomposition test. 6. By the action of ${\beta}-N-acetyl$ glucosaminidase the N-acetylated spot A compound was completely decomposed into N-acetyl glucosamine, whereas the spot B compound was not. This indicated the spot A compound has a beta-linkage. 7. When phosphodiesterase or phosphomonoesterase acted on $^{32}P-labeled$ spot B compound, $^{32}P$ was not released by phosphodiesterase, but completely released by phosphomonoesterase. This indicated that one phosphorus is linked to glucosamine moiety. 8. The spot A compound is assumed to have the following chemical structure: That is glucosaminyl, ${\beta}-1$, 6-glucosamine to which O-acyl and N-acyl fatty acids are linked, of which the predominant fatty acid is beta-OH $C_{13:0}$ fatty acid in addition to beta-OH $C_{9:0}$ fatty acid 9. The spot B compound is likely to have the linkage of $glucosaminyl-{\beta}-1$, 6-glucosamine to which phosphorus is linked in monoester linkage. Furthermore both O-acyl and N-acyl fatty acids contained beta-OH $C_{13:0}$ fatty acid predominantly in addition to beta-OH $C_{9:0}$ fatty acid.

• Korean Journal of Environmental Agriculture
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• v.12 no.1
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• pp.41-49
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• 1993

The Study was conducted to develope the low temperature tolerant methane-producing bacteria(LTTB) and to increase the efficiency of anaerobic fermentation for the treatment of agricultural and livestock wastes at low temperature. The samples were collected from muddy soil, water logged sediment, organic layer and anaerobic sludge at three latitudes, $34.8{\sim}37.4\;^{\circ}N(Korea)$, $41.4\;^{\circ}N(USA)$ and $54.5{\sim}56.9\;^{\circ}N(Canada)$. They were used for determination of the methanogenesis rates for isolation and identification of the LTTB. The methanogenesis rate of smaples at low temperature were higher in the cellulose medium than methanol medium. The methanogenesis rate in the samples of subarctic region were $15{\sim}19$ moles/ml during 30 days at low temperature($8\;^{\circ}C$), whereas not detected in the samples of temperate region. The methanogenesis rate in the enrichment culture of subarctic samples were inhibited by the $40\;{\mu}g/ml$ of streptomycin + vancomycin or ampicillin + oleandomycin which were not effect to the methanogens. An inhabitation of high temperature tolerant methane producing bacteria was identified in the samples of temperate region, whereas that of the LTTB growing at $8{\sim}13^{\circ}C$ was identified in the subarctic region.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.99-99
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• 1999

투명전도막인 Ito(Indium Tin Oxide)는 flat panel display 와 solar cell 같은 optoelectronic 이나 microelectronic device에서 널리 이용되어 지고 있다. 현재 상용화되고 있는 거의 대부분의 ITO 박막은 sputtering법에 의해 제조되고 있으나 공정상의 이유로 15$0^{\circ}C$이상의 기판온도가 요구되어진다. 그런, 실제 display device 제조공정에서는 비정질 실리콘 박막이나 유기막 위에 ITO박막을 제작할 필요성이 증대되어 지고 있고, 또한 다른 전자소자에 있어서도 상온 ITO 박막 형성 공정에 대한 필요성이 증대되고 있다. 이러한 이유로 본 실험에서는 IBAE(Ion Beam Assisted Evsporation)을 이용하여 저온 ITO박막을 유기막 위에 증착하는 공정에 대한 연구를 수행하였다. 이렇게 증착된 ITO 박막의 결정성은 비정질이었다. 또한, 모든 display device 제작에는 식각공정이 필수인데 기존에 사용되고 있는 wet etching 법은 등방성 식각특성 때문에 미세 pattern 형성에 부적합？, 따라서 비등방성 식각에 용이한 plasma etching법을 사용하여 저온 증착된 ITO 박막의 식각특성을 알아보았다. 실험에 사용된 식각장비는 자장 강화된 유도결합형 플라즈마 식각장비(MEICP)를 사용하였으며, 13.56MHz의 RF power를 사용하였다. 식각조건으로 source power는 600W~1000W, 기판 bias boltage는 -100V~-250V를 가하였으며, Ar, CH4, O2, H2, BCl3의 식각 gases, 5mTorr~30mTorr의 working pressure 변화 그리고 기판 온도에 따른 식각특성을 관찰하였다. ITO 가 증착된 기판으로는 유기물 중 투명전도성 박막에 기판으로서 사용가능성이 클 것으로 기대되어지는 PET(polyethylene-terephtalate), PC(polycarbonate), 아크릴을 사용하여 기판 변화가 식각특성에 미치는 영향에 대해서 각각 관찰하였다. 식각속도의 측정은 stylus profiler를 이용하여 측정하였으며 식각후에 표면상태는 scanning electron spectroscopy(SEM)을 이용하여 관찰하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.178-181
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• 2008

다양한 조성을 갖는 $CH_4+CO_2$ 혼합 기체 하이드레이트 샘플의 미세 구조 분석을 위하여 X-ray 회절 방법을 이용하였다. X-ray 회절 분석을 이용할 경우, 하이드레이트로의 전환율과 같은 정성적인 분석뿐 아니라 각 객체별 cage occupancy와 같은 정량적인 분석까지도 가능한 것으로 나타났다. 또한 이렇게 얻어진 X-ray 회절 분석 결과 및 refinement 결과를 $^{13}C$ 고체 NMR 방법과 교차 비교함으로써 측정 결과의 신뢰도를 높이려 하였다. 얻어진 분석 결과는 이후 가스 하이드레이트를 이용한 다양한 연구 분야에서 저장용량 평가 및 객체 점유율과 같은 미세 구조 정보를 얻는 데에 유용하게 사용될 것으로 전망된다.

• Journal of Hydrogen and New Energy
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• v.32 no.1
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• pp.68-76
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• 2021

Climate change problems occur during the use of fossil fuel and the process of biogas production. Research continues to convert carbon dioxide and methane, the major causes of climate change, into high-quality energy sources. in order to present the performance potential for the novel plasma-recuperative burner reformer, the reforming characteristics for each variable were indentified. The optimal operating condition of was an O2/C ratio of 1.0 and a total gas supply of 20 L/min. At this time, CH4 conversion was 64%, H2 selectivity was 39%, and H2/CO ratio was 1.13, which were the results applicable to the solid oxide fuel cell fuel stack for RPG, or Residential Power Generator. Recirculation of reformed gas increases the amount of H2 and CO, which are combustible gases, especially the amount of H2. As a result, the H2 selectivity is improved, and high-quality gas can be produced.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1043-1047
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• 2004

Thirteen compounds were isolated from the $CH_2Cl_2$ fraction of Machilus thunbergii as phospholipase $C{\Upsilon}1\;(PLC{\Upsilon}1)$ inhibitors. These compounds were identified as nine lignans, two neolignans, and two flavans by spectroscopic analysis. Of these, 5,7-di-O-methyl-3',4'-methylenated (-)-epicatechin (12) and 5,7,3'-tri-O-methyl (-)-epicatechin (13) have not been reported previously in this plant. In addition, seven compounds, machilin A (1), (-)-sesamin (3), machilin G (5), (+)-galbacin (9), licarin A (10), (-)-acuminatin (11) and compound 12 showed dose-dependent potent inhibitory activities against $PLC{\Upsilon}1$ in vitro with $IC_{50}$ values ranging from 8.8 to 26.0 ${\mu}M$. These lignans, neolignans, and flavans are presented as a new class of $PLC{\Upsilon}1$ inhibitors. The brief study of the structure activity relationship of these compounds suggested that the benzene ring with the methylene dioxy group is responsible for the expression of inhibitory activities against $PLC{\Upsilon}1$. Moreover, it is suggested that inhibition of $PLC{\Upsilon}1$ may be an important mechanism for an antiproliferative effect on the human cancer cells. Therefore, these inhibitors may be utilized as cancer chemotherapeutic and chemopreventive agents.