• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.185-198
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• 2008

Influences of dietary brown seaweed(BSW) on the nutrient metabolism, anti-oxidant enzyme activity and cell-mediated immune response were studied in broiler chicks activated acute phase response. 72 Hatched male broiler chicks(Ross) were divided into 12 pens, 6 heads per pen, and fed the BSW 0.0% (Basal) or 2.0% diet, respectively, and injected with the Salmonella typhimurium lipopoly saccharide(LPS) for activation of the acute phase response three times at 8, 10 and 12 d of age. During 4 wks of experimental feeding, growth performance of broiler chicks was not affected by dietary BSW and the acute phase response. Compared with control birds, the acute phase response did not affect the daily weight gain in birds fed BSW 2.0% diet, decreased nitrogen balance(NB) or metabolizable energy(ME) utilization per metabolic body size(kg0.75), and enhanced activities of peroxidase or extracellular SOD(EcSOD), tumor necrosis factor-alpha and ovotransferrin in plasma and MnSOD and CuZnSOD in erythrocyte cytosol. Compared to BSW 0.0% diet, 2.0% diet enhanced protein retention(NB) per kg0.75 regardless the acute phase response, did not affect uric acid nitrogen excretion(UAN) per kg0.75 in birds during the acute phase response, decreased(p<0.05) the UAN excretion per kg0.75 in control birds. And BSW 2.0% diet also decreased(p<0.05) plasma peroxide level and erythrocyte peroxidase or MnSOD activity but increased plasma peroxidase and EcSOD activity and interleukin-1 activity secreted from LPS-stimulated PBMC in 4 week broiler chicks.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.1-20
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• 1997

목재를 분해시키는 담자균류들은 목재 및 목질복합체에 쉽사리 침투하여 복잡한 리그노셀룰로오스 복합체를 분해시킨다. 이러한 분해에는 많은 효소시스템들이 복합적으로 작용하면서 상호 협동하는 것으로 보고되고 있다. 지금까지 일려진 효소들은 통상 3개의 그룹으로 나눌 수 있는데 그 하나는 목재성분을 직접적으로 공격하는 효소균들, 예를 들면 cellulase complex, laccase(LAC), lignin peroxidase(LIP), horse-radish peroxidase(HRP), manganese-independent peroxidase(MIP) 및 protocatechuate 3,4-dioxygenase(PCD) 등이 있고, 두번째 그룹으로서 manganese-dependent peroxidase(MnP), aryl alcohol oxidase(AAO) 및 glyoxal oxidase(GLO) 등인데, 이들 효소들은 목질을 직접적으로 공격하지 않고 제1그룹의 효소들과 협동하여 작용하는 것으로 알려지고 있다. 제3그룹의 효소들은 glucose oxidase(GOD) 및 cellobiose : quinone oxidoreductase(CBQ)로서 feedback type의 효소들로서 목재고분자의 분해시 대사의 고리를 결합시켜 주는 매우 중요한 기능을 하는 효소군들이다. 그러나 이 이외에도 다른 분해기구가 밝혀지고 있으며 기타 효소들에 의한 리그노셀룰로오스의 분해반응기구의 해명에는 상당한 시간이 걸릴 것으로 사료된다.

• Microbiology and Biotechnology Letters
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• v.42 no.1
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• pp.11-17
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• 2014

Selenium is an essential trace element for mammals, but it is very toxic. Therefore, the control of selenium concentrations should be precisely and effectively monitored. Selenium is naturally obtained through foods and seleno-L-methionine (LSeMet) is a major form of selenium. It has been reported that L-SeMet is only converted into Se-adenosyl-L-SeMet. However, a recent study suggested that L-SeMet was directly metabolized into methylselenol ($CH_3SeH$) in mouse liver extract by the reaction of cystathionine ${\gamma}$-lyase (CGL). The canonical reaction of CGL was known to catalyze the cleavage of L-cystathionine to L-cysteine, ${\alpha}$-ketobutyrate and $NH_3$. In the present study, we found that L-SeMet could be directly converted to $CH_3SeH$ using purified homogenous human CGL instead of mouse liver cytosol. Authentic $CH_3SeH$ was prepared by reduction of dimethyldiselenide with sodium tetrahydroborate. The gaseous product of the enzymatic reaction with L-SeMet was analyzed by GC/MS spectrometry. The GC/MS data was identical to that of authentic dinitrophenyl selenoether. We also analyzed the kinetic parameters for the formation of $CH_3SeH$ from L-SeMet by human and mouse CGL. These results suggest that human CGL is a critical enzyme which is responsible for L-SeMet metabolism.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.181-181
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• 1994

포유 동물의 중추 신경계에서 주 억제성 신경전달물질로 알려진 4-aminobutyrate(GABA) 대사에 관여하는 효소인 GABA transaminase (GhBA-T)와 Succinic semialdehyde reductase(SSR)를 각각 여러 가지 크로마토그래픽 방법을 사용하여 순수 분리 정제하였다 GABA-T는 subunit 분자량 50kDa을 가진 dimer이며 화학 변형(chemical modification), 흡광, 형광스펙트럼 연구에 의하면 cysteinyl잔기가 활성 부위에 존재하고 있음을 보여주었다 SSR은 2-mercaptoethanol이 존재하든 안하든 o-pthalaldehyde(OPA)에 의하여 효소 활성도가 상실되었으며 흡광 및 형광스펙트럼에 의하면 OPA가 효소의 활성 부위의 lysyl잔기와 반응하여 cysteinyl잔기와 함께 intermolecular cross-linking을 이루는 것을 알 수 있었다. 한편 SSR은 몇가지 anticonvulsant drug에 의하여 부분적인 저해 효과를 나타내었다.

• Journal of Food Hygiene and Safety
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• v.2 no.1
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• pp.35-40
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• 1987

The antilipidperoxidative effects of Brazilin and Hematoxylin were investigated at the levels of liver~total homogenates, -microsomal fraction, -mitochondrial fraction and the sera of SD-rats intoxicated with $CCl_4$ and ethanol. Both natural dyes markedly inhibited the lipidperoxidation induced by $CCl_4$ and ethanol. Brazilin and Hematoxylin showed the inhibitory effects on the both enzymatic (NADPH-dependent) and nonenzymatic (Ascorbate-induced) lipidperoxidation pathways. but it is supposed that the antilipidperoxidative powers of them mainly result from the inhibition of the nonenzymatic lipidperoxidation.

• KSBB Journal
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• v.16 no.6
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• pp.527-532
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• 2001

Trichlooethylene (TCE) has become a widespread contaminant in air, soil, and underground water due to extensive industrial used and improper disposals. Since TCE is a suspected carcinogen and constitutes public health concerns, many treatment systems have been investigated to remove this hazardous waste. One of the most premising reactor systems for the treatment of TCE is trickling biofilter (TBF), in which monooxygenase (MO), the corresponding enzyme for initiating primary substrate oxidation, fortuitously degrades TCE via cometabolism. TCE, however, is not easily treated by simple TBF. This is mainly due to the toxicities of TCE and its degradation products to microbial film in TBF. In this paper, recent progresses on the development of bioreactor system for the treatment of TCE, especially gas-phase TCE, are reviewed. The potentials of novel biofilm reactor systems were also discussed for the long-term continuous treatment of TCE.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.133-133
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• 1993

DA-125의 rat blood중 분해반감기는 4.28분으로, DA-125는 정맥 투여후 신속히 M1으로 분해되었으며, DA-125는 투여 10분 후부터 검출되지 않았다. Mouse에 25mg/kg 정맥주사 한 후의 M1의 phamacokinetic parameter는 terminal t$\frac{1}{2}$ 344분, MRT 371분, Vss 25.7 $\ell$/kg, CL$_{total}$ 69.3 ml/min/kg이었으며 투여 2hr후에 M1및 대사체가 폐, 위, 신장등에는 다량 존재하였으나 심장에서는 검출되지 않았다. Rat에 10 mg/kg 정맥주사한 후의 혈장농도는 terminal phase에 도달하지 못하고 혈장농도가 변동을 나타내었다. 담즙으로의 배설은 주로 M2의 형태로 이루어졌으며 M1이 소량 차지하고 M3와 M4는 검출되지 않았다. DA-125는 rat 및 mouse liver homogenate에 의해 대사되어 FT-ADM(M1) ,13-dihy-dro FT-ADM(M2), 7-deoxy-adriamycinone(M3) 및 7-deoxy-13-dihydro adriamyci-none(M4)를 형성하였다. DA-125는 혐기, 호기 및 보효소, 종차에 관계얼이 반응개시 30분후에 약 90%가 분해되었으나 각 대사체의 생성여부 및 속도는 조건에 따라 변화하였다.

• Journal of Plant Biotechnology
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• v.41 no.4
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• pp.169-179
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• 2014

Intracellular antioxidants include low molecular weight scavengers of oxidizing species, and enzymes which degrade superoxide and hydroperoxides. Such antioxidants systems prevent oxidative damage to cellular component by scavenging free radicals and activated oxygen species. Hydrophobic scavengers are found in cell membrane where they interrupt chain reactions of lipid peroxidation. The three major lipophilic antioxidant classes for human health are carotenoids, vitamin E and coenzyme Q10. The biofortification of staple crops with these lipid soluble antioxidants is an attractive strategy to increase the nutritional quality of human food. Here, we have summarized the biosynthetic pathways of three lipid soluble antioxidants in plants and current status of genetic engineered plants for elevated levels of each lipophilic antioxidant.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.171-176
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• 2004

Nonyphenol (NP) used actively as non-ionic surfactant is classified as one of most potent endocrine disrupting chemicals. Effects of NP on mixed function oxygenase (MFO) system in rockfish (Sebastes schlegeli) were investigated for seven days after intraperitoneal injection (10 and 25 mg $kg^{-1}$). Hepatosomatic index (BSI) of fishes exposed to NP of 25 mg $kg^{-1}$ was significantly reduced compared to those in control group. NP exposure enhanced cytochrome P450 levels in the fish liver, while 7 ethoxyresorufin-O-deethylase (EROD) activity was inhibited. NP exposure levels in this study were much higher than those found in the coastal environment of Korea. Effects on HSI and liver MFO system, which is involved in steroid hormone metabolism, imply that W may influence on reproduction of fish by not only hormone receptor mediated response but also through effects on the MFO system.

• Journal of The Korean Association For Science Education
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• v.27 no.3
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• pp.212-224
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• 2007

Metabolism is one of the pivotal biology concepts, but many students have difficulty understanding it. The purposes of this study were (1) to explore 8th graders' conceptual change of an enzyme after classes of experimenting enzyme reaction and interpreting data using systematic analogies, (2) to discover the role of systematic analogies to enhance students' understanding, and (3) to explain students' difficulty understanding concepts as the ontological features. Systematic analogies were designed to encourage students to interpret their lab activities on enzyme reaction rates. Data were collected by using the pre-test and the post-test of open-ended form, students' worksheets, and interviews with students. After classes, the number of students to engender scientific conceptions about the function of enzyme, its structure, and its mechanism has increased. But more students failed to understand the reaction mechanisms having ontological features of equilibration processes than to understand the function of enzyme having ontological features of event-like processes. Even though the concepts of enzymes are hard to grasp owing to their ontological attributes of equilibration processes, a part of students' conceptions successfully progressed from the idea belonging to event-like processes to one belonging to equilibration processes. And systematic analogies were found to contribute in enhancing students' conceptual change of the enzyme reaction.