• Title/Summary/Keyword: substrate effects

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Oxidation of Ethanol in the Gas Phase with Alcohol Oxidase and Alcohol Dehydrogenase (Alcohol Oxidase와 Alcohol Dehydrogenase를 이용한 기상에서의 Ethanol의 산화반응)

  • 박현규;장호남김동옥
    • KSBB Journal
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    • v.9 no.3
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    • pp.239-245
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    • 1994
  • The effects of reaction temperature and the level of hydration(water activity) were studied for gas phase reactions of alcohol oxidase and alcohol dehydrogenase immobilized on DEAE-cellulose and controlled pore glass(CPG). Optimum reaction temperature zone of gas phase reaction was similar to that of aqueous phase reaction. The activity of alcohol oxidase increased dramatically and the stability decreased when the water activity was increased from 0.3 to 0.8. The apparent activation energies of the gas phase reaction decreased approaching the values obtained in the aqueous phase reaction as the water activity increased. In the both cases of alcohol oxidase and alcohol dehydrogenase, the rate constants of the gas phase reaction were lower than those of aqueous phase reaction by two orders of magnitude and these results could be correlated to the vapor-liquid equilibrium data of the substrate, ethanol.

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Antioxidative Effect of Loaves of Cedrela sinensis Extracts on Linoleic Acid and Soybean Oil (참죽나무 잎 추출물의 대두유에 대한 항산화 효과)

  • 조희숙
    • Journal of the East Asian Society of Dietary Life
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    • v.9 no.1
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    • pp.100-106
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    • 1999
  • The antioxidative effect of leaves of Cedrela sinensis on 0.1M-linoleic acid was compared with some commercial antioxidants during storage at 50$\pm$2$^{\circ}C$ for 20 hours, and on soybean oils at 60$\pm$2$^{\circ}C$ for 30days. In the oxidation of linoleic acid, antioxidative effects of various leaves of Cedrela sinensis extracts and other antioxidants were shown in the following orders: 3% leave of Cedrela sinensis methanol extract>1% leave of Cedrela sinensis methanol extract>0.02% BHT>3% leave of Cedrela sinensis ethyl acetate extract>0.5% leave of Cedrela sinensis methanol extract>0.02% tocopherol>leave of Cedrela sinensis methanol extract 0.1, 0.02%>leave of Cedrela sinensis ethyl acetate extract 1, 0.5, 0.1, 0.02%>control, while in the oxidation of soybean oil, 1% leave of Cedrela sinengis methanol extract>0.02% BHT>3% leave of Cedrela sinengis methanol extract>0.02% tocopherol>control. The relative antioxidant effectiveness (RAE) were shown to be available in all substrates and the best effect was shown in substrate added compound of 3% leave of Cedrela sinensis methanol extract.

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Regulation of IgE and Type II IgE receptor expression by insulin-like growth factor-1: Role ofSTAT6 and $NF-{\kappa}B$.

  • Koh, Hyun-Ja;Park, Hyun-Hee;Lee, Choong-Eun
    • BMB Reports
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    • v.33 no.6
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    • pp.454-462
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    • 2000
  • Interleukin-4(IL-4) is known to be a major cytokine regulating immunoglobulin E(IgE) response by the induction of IgE production and type II IgE receptor(IgER II: CD23) expression. Recently, however, the role of neuroendocrine factors has been implicated in modulating the IgE response. Among various neuroendocrine growth factors, we investigated the effects of the insulin-like growth factor-1(IGF-1) since IL-4 and IGF-1 share common intracellular signaling molecules, such as the insulin receptor substrate-1/2(IRS-1/2) to induce a specific cellular response. In the human peripheral blood mononuclear cell (PBMC) cultures, IGF-1 was capable of inducing a substantial level of IgE production in a dose-dependent manner. It also noticeably upregulated the IL-4-induced or IL-4 plus anti-CD40-induced IgE production. Similarly, the IGF-1-induced IgE production was enhanced by IL-4 or anti-CD40 in an additive manner, which became saturated at high concentrations of IGF-1. Although IGF-1 alone did not induce IgER II (CD23) expression, it augmented the IL-4-induced surface CD23 expression in a manner similar to the action of anti-CD40. These results imply that IGF-1 is likely to utilize common signaling pathways with IL-4 and anti-CD40 to induce IgE and IgER II expression. In support of this notion, we observed that IGF-1 enhanced the IL-4-induced signal transducers and activators of transcription 6(STAT6) activation and independently induced $NF-{\kappa}B$ activation. Both of these bind to the IgE(C) or IgER II (CD23) promoters. Together, our data suggest that IL-4 and IGF-1 work cooperatively to activate STAT6 and $NF-{\kappa}B$. This leads to the subsequent binding of these transcription factors to the $C{\varepsilon}$ and CD23 promoters to enhance the expression of IgE and IgER II. The observed differential ability of IGF-1 on the induction of IgE vs. IgER II is discussed based on the different structure of the two promoters.

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Purification and Characterization of Gibberellin $3Beta$-Hydroxylase from Immature Seeds of Phaseolus vulgaris (강낭콩미숙종자로부터 Gibberellin $3Beta$-Hydroxylase 정제 및 성질)

  • 곽상수
    • Proceedings of the Botanical Society of Korea Conference
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    • 1987.07a
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    • pp.133-148
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    • 1987
  • Gibberellin(GA) 3-$\beta$ hydroxylation is very important for the shoot elogation in the higher plants, since only 3$\beta$-hydryoxylated GAs promote shoot elogation in several plants. Fluctuation of 3$\beta$-hydryoxylase activity was examined during seed maturation using two cultivars of , P. vulgaris, Kentucky Wonder (normal) and Masterpiece (dwarf). Very immature seeds of both cultivars contain high level of 3$\beta$-hydroxylase activity (per mg protein). Both cultivars showed maximum of enzyme activity (per seed) in the middle of their maturation process. Gibberellin 3$\beta$-hydroxylase catalyzing the hydroxylation of GA20 to GA1 was purified 313-fold from very early immature seeds of P. vulgaris. Crude soluble enzyme extracts were purified by 15% methanol precipitation, hydrophobic interaction chromatogrphy, DEAE ion exchange column chromatography and gel filtration HPLC. The 3$\beta$-hydroxylase activity was unstable and lost much of its activity duting the purification. The molecular weight of purified enzyme was extimated to be 42, 000 by gel filtration HPLC and SDS-PAGE. The enzyme exhibited maximum activity at pH 7.7. The Km values for [2.3-3H] GA20 and [2.3-3H]GA9 were 0.29 $\mu$M and 0.33 $\mu$M, respectively. The enzyme requires 2-oxoglutarate as a cosubstrate; the Km value for 2-oxoglutarate was 250 $\mu$M using 3H GA20 as a substrate. Fe2+ and ascorbate significantly activated the enzyme at all purification steps, while catalase and BSA activated the purified enzyme only. The enzyme was inhibited by divalent cations Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+. Effects of several GAs and GA anaogues on the putrified 3$\beta$-hydroxylase were examined using [3H]GA9 and GA20 as a substrates. Among them, GA5, GA9, GA15, GA20 and GA44 inhibited the enzyme activity. [13C, 3H] GA20 was converted by the partially purified enzyme preparation to [13C, 3H]GA1, GA5 and GA6, which were identified by GC-MS, GA9 was converted only GA4, GA15 and GA44 were converted to GA37 and GA38, respectively. GA5 was epoxidized to GA6 by the preparation. This suggests that 3$\beta$-hydroxylation of GA20 and epoxidation of GA5 are catalyzed by the same enzyme in P, vulgaris.

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Antiplatelet Activity of [5-(2-Methoxy-5-chlorophenyl)furan-2-ylcarbonyl]guanidine (KR-32570), a Novel Sodium/hydrogen Exchanger-1 and Its Mechanism of Action

  • Lee Kyung-Sup;Park Jung-Woo;Jin Yong-Ri;Jung In-Sang;Cho Mi-Ra;Yi Kyu-Yang;Yoo Sung-Eun;Chung Hun-Jong;Yun Yeo-Pyo;Park Tae-Kyu;Shin Hwa-Sup
    • Archives of Pharmacal Research
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    • v.29 no.5
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    • pp.375-383
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    • 2006
  • The anti platelet effects of a novel guanidine derivative, KR-32570 ([5-(2-methoxy-5-chlorophenyl) furan-2-ylcarbonyl]guanidine), were investigated with an emphasis on the mechanisms underlying its inhibition of collagen-induced platelet aggregation. KR-32570 significantly inhibited the aggregation of washed rabbit platelets induced by collagen $(10{\mu}g/mL)$, thrombin (0.05 U/mL), arachidonic acid $(100{\mu}M)$, a thromboxane (TX) $A_2$ mimetic agent U46619 (9,11-dideoxy-9,11-methanoepoxy-prostaglandin $F_2,\;1{\mu}M$) and a $Ca^{2+}$ ATPase inhibitor thapsigargin $(0.5{\mu}M)$ ($IC_{50}$ values: $13.8{\pm}1.8,\;26.3{\pm}1.2,\;8.5{\pm}0.9,\;4.3{\pm}1.7\;and\;49.8{\pm}1.4{\mu}M$, respectively). KR-32570 inhibited the collagen-induced liberation of $[^3H]$arachidonic acid from the platelets in a concentration dependent manner with complete inhibition being observed at $50{\mu}M$. The $TXA_2$ synthase assay showed that KR-32570 also inhibited the conversion of the substrate $PGH_2$ to $TXB_2$ at all concentrations. Furthermore, KR-32570 significantly inhibited the $[Ca^{2+}]_i$ mobilization induced by collagen at $50{\mu}M$, which is the concentration that completely inhibits platelet aggregation. KR-32570 also decreased the level of collagen $(10{\mu}g/mL)$induced secretion of serotonin from the dense-granule contents of platelets, and inhibited the NHE-1-mediated rabbit platelet swelling induced by intracellular acidification. These results suggest that the antiplatelet activity of KR-32570 against collagen-induced platelet aggregation is mediated mainly by inhibiting the release of arachidonic acid, $TXA_2$ synthase, the mobilization of cytosolic $Ca^{2+}$ and NHE-1.

Experimental Research on the Surface Changes and the Abrasion Resistance of Pit and Fissure Sealant by Fluoride (불소도포제에 의한 치면열구전색제의 마모저항성과 표면 변화에 관한 실험연구)

  • Hwang, Su-Hyun;Yu, Ji-Su
    • Journal of dental hygiene science
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    • v.10 no.5
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    • pp.373-378
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    • 2010
  • To test the effects of representative fluoride vanishes-1.23% APF gel and 5% NaF Fluoride Varnish-on the surface structure of pit and fissure sealant, this study classified samples of pit and fissure sealant into five groups: Group I deposited in distilled water for ten minutes, Group II treated with APF gel for one minute, Group III treated with APF gel for four minutes, Group IV treated with Fluoride Varnish for one minute, and Group V treated with Fluoride Varnish for four minutes. An abrasion test was carried out to measure changes in weight, along with observation of the surface structure by using an optical microscope, consequently drawing the following conclusions. 1. The results of the abrasion test using pit and fissure sealant, Concise, showed that Group III had the reduction in weight more increased than Group I and that Group V had less reduction in weight (p<0.05); the results of the abrasion test using Eco-S showed Group III had the reduction in weight more increased than Group I and that Group V had less reduction in weight (p<0.05). 2. The results of observation using an optical microscope showed that application of APF gel made the filler remarkable due to loss of substrate and that Group III treated with APF gel for four minutes had the toughest surface, followed by Group II treated with APF gel for one minute, Group I deposited in distilled water for ten minutes, Group IV treated with Fluoride Varnish for one minute, and Group V treated with Fluoride Varnish for four minutes.

Development of Particle-level Computer Assisted Instruction Materials for the ‘Solution’ Chapter in High School Chemistry Textbook and Analysis of the Educational Effects (고등학교 화학 교과서의 ‘용액’ 단원에 대한 입자 수준의 컴퓨터 보조 수업자료 개발 및 적용 효과 분석)

  • Baek, Seong-Hye;Kim, Jong-Hyeon;Kim, Jeong-Won;Park, Chan-Geun
    • Journal of the Korean Chemical Society
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    • v.50 no.2
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    • pp.163-177
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    • 2006
  • Alpha Nickel hydroxide samples have been synthesized by electrodeposition on platinum and nickel substrates at current densities of 1, 5, 6, 7 and 10 mAcm?2 at a controlled temperature of 30.00 oC from Ni(NO3)2 bath. Platinum substrate shows a tendency to incorporate less nitrate ions with increase in current density thus producing less hydroxy-deficient nickel hydroxide layers. On the whole the interlayer distance (d003) is found to be inversely proportional to the amount of nitrate ions incorporated in-between the lattice. For the first time we have observed a decrease in lattice spacing with increase in concentration of intercalant (anions) and the reason for lattice contraction is attributed to the columbic attractive forces exerted by the oppositely charged nitrate ion and positively charged slabs. The Infrared spectra of the samples with expanded interlayers show two types of OH vibrations corresponding to hydrogen bonded and non-hydrogen bonded OH groups whereas the contracted interlayers show only hydrogen-boded OH groups. Although the faradaic efficiency is found to increase with increase in applied current there is a local minimum at 6.0 mAcm?2 current density on both platinum and nickel substrates. In this manuscript, GC-MS data is provided which clearly demonstrates the electrodeposited nickel hydroxide sample to consist of huge amount of carbonate ions although the electrolyte solution in nickel nitrate.

Preparation and Adhesion of One Part Room Temperature Curable Alkoxy Type Silicone Sealant (일액형 알코올형 실리콘 실란트의 제조 및 접착 물성)

  • Kim, Dae-Jun;Park, Young-Jun;Kim, Hyun-Joong;Lee, Bong Woo;Han, Jae Chul
    • Journal of Adhesion and Interface
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    • v.2 no.4
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    • pp.1-9
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    • 2001
  • Silicone sealants are composed of polymer, plasticizer, crosslinker, catalyst and filler. Types and compositions of components are effected on sealant performances. In recent, use of alkoxy type silicone sealant increased due to environmental advantage. In this study, we investigated effects of component types and ratios on one-part room temperature curable alkoxy type silicone sealant preparation and adhesion properties. Alkoxy type silicone sealants were prepared with various PDMS (polydimethylsiloxane) viscosities. In addition, the effect of plasticizer, crosslinkers, and catalyst on sealant obtained from by mixture of PDMS viscosities of 20000 and 80000 was investigated. Reaction temperature on change of mixing time was observed, and then proper crosslinking systems were found. Adhesion (properties) of silicone sealants were measured. In the sealants preparation, stable reaction was achieved by adjusting composition variance ratio in the sealant mixture temperature below $40^{\circ}C$. The adhesion properties of sealant differ from substrate composition. The order of adhesion strength was glass/glass > glass/aluminum > aluminum/aluminum system. The elongation of sealant was increased as polymer viscosity and plasticizer content increased. The strength was increased as crosslinker and plasticizer decreased, while catalyst increased.

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Physio-Chemical Studies on the After-Ripeng of Hot Pepper Fruit -Part VII. Effects of Ethephon on the Major Compoments- (신미종(辛未種) 고추의 추숙(追熟)에 관(關)한 생리화학적(生理化學的) 연구(硏究) -제7보 주요성분(主要成分)에 미치는 Ethephon의 효과(?果)-)

  • Lee, Sung-Woo;Kim, Kwang-Soo;Kim, Soon-Dong
    • Korean Journal of Food Science and Technology
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    • v.7 no.4
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    • pp.194-199
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    • 1975
  • The physiological and chemical investigations to explain the after-ripening processes in got green pepper fruit were carried out by treating the fruit with ethephon either alone or with phenylalanine. The studied metabolic changes in fruit during after-ripening period was carbon dioxide and oxygen concentration in interior of the pepper fruit, total carotenoid, ${\beta}-carotene$, total sugar, and free reducing sugar in pepper fruit. These metabolic changes were explained inrelation to the color enhancement judged by the color score to explain the after-ripening processes. Ethephon treatment at 500 ppm significantly accelerated color enhancement as compared to the control and further ethephon treatment increased the number by 20 percent which was not possible in control during same after-ripening period. The oxygen concentration in interior of the pepper fruit during after-ripening period was increased in control when the color score (color enhancement) increased rapidly. However, with ethephon treatment, the oxygen concentration was decreased when the color score increased. Although total and free reducing sugar content were decreased during the after-ripening period total carotenoid and ${\beta}-carotene$ content was increased by 50 and 200 percent, respectively, over control. Also the capsaicin contents was increased by 20 percent by ethephon treatment over control. Although phenylalanine treatment did not affect the capsaicin content, capsaicin content tended to be increased by phenylalanine treatment when treated with ethephon. Acknowledgements: This work was supported by funds from Korean Traders Scholarship Foundation.

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Effect of the Dietary Supplementation of Fermented Spent Mushroom (Pleurotus eryngii) Substrates on the Growth Performance and Carcass Characteristics in Hanwoo Steers (새송이버섯 수확 후 배지 발효산물 첨가급여가 한우 거세우의 성장과 도체등급에 미치는 영향)

  • Gal, Sang-Wan;Moon, Yea-Hwang;Cho, Soo-Jeong
    • Journal of Life Science
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    • v.21 no.12
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    • pp.1705-1709
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    • 2011
  • This study was carried out to investigate the feeding effects of the dietary supplementation of fermented spent mushroom (Pleurotus eryngii) substrates with Bacillus amyloliquefaciens CS47 and Saccharomyces cerevisiae (F-SMS) on growth performance and carcass characteristics of Hanwoo steers. Thirty two Hanwoo steers were allocated into two feeding groups and assigned equally to two dietary treatments; Control (commercial formula feed for Hanwoo steers and rice straw) and TMR including 30% F-SMS. The nutritional values of TMR including 30% F-SMS was higher crude protein (11.67%) and TDN (72.11%) than rice straw, but not significantly different from commercial formula feed (p<0.05). Feed intake was significantly greater in the TMR including 30% F-SMS than the control (p<0.05), but body weight gain and carcass grades were not influenced by the experimental diets. Based on this study, fermented spent mushroom (Pleurotus eryngii) substrate with Bacillus amyloliquefaciens CS47 and Saccharomyces cerevisiae is may be used as an ingredient of feed in TMR for Hanwoo steer.