• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.808-811
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• 2001

The rheological properties of exopolysaccharide(EPS-R) produced by marine bacteria Hahella chjuensis KCTC 2395 was investigated. EPS-R solution showed a characteristic non-Newtonian behavior fluid properties. In aqueose dispersions of EPS-R 1%, consistency index(K) and flow behavior index(n) were 1,410 cp and 0.73. EPS-R solution was pseudoplastic fluid by power-low model. Rheological propertie of EPS-R was found to be influenced by the concentration of salt, pH, temperature and ionic compounds.

• Korean Journal of Microbiology
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• v.14 no.3
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• pp.99-99
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• 1976

Some properties of xylanase produced by Pleurotus ostreatus during its gorwth in a rice straw medium were investigated. The results are summarized as follows : 1) The optimum pH of xylanase was 5.0 and the stable pH ranged from 4.5 to 6.0. 2) The optimum temperature for the xylanse was around $50^{\circ}C$ and the xylanse activity was completely lost in 10 minutes at $70^{\circ}C$ 3) The activity of xylanse was inhibited by managanous ion, but was increased by other metalic ions. Especially K, Mg and Ca ions considerably increased the activity.

• Korean Journal of Microbiology
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• v.14 no.3
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• pp.93-104
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• 1976

Some properties of xylanase produced by Pleurotus ostreatus during its gorwth in a rice straw medium were investigated. The results are summarized as follows : 1) The optimum pH of xylanase was 5.0 and the stable pH ranged from 4.5 to 6.0. 2) The optimum temperature for the xylanse was around $50^{\circ}C$ and the xylanse activity was completely lost in 10 minutes at $70^{\circ}C$ 3) The activity of xylanse was inhibited by managanous ion, but was increased by other metalic ions. Especially K, Mg and Ca ions considerably increased the activity.

• YAKHAK HOEJI
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• v.30 no.3
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• pp.157-162
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• 1986

$\alpha$-Adrenoceptor subtypes in the isolated rat aortic strips were examined by using agonists and antagonists which have varying selectivity for $\alpha_1$- and $\alpha_2$- adrenoceptors. Norepinephrine and phenylephrine produced a similar magnitude of maximum contractions. $pA_2$ values for prazosin and yohimbine were not significantly different using norepinephrine or phenylephrine as the agonist, suggesting a single population of alpha-adrenoceptor. Contractile responses produced by alpha-agonists were antagonized more effectively by prazosin (approximately 1000 fold) than by yohimbine.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.219-227
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• 2008

Bacillus thuringiensis was isolated as a pathogen of the sotto disease of silkmoth larvae about a hundred years ago. Since then, this bacterium has attracted attentions of not only insect pathologists but also many other scientists who are interested in its strong and specific insecticidal activity. This has led to the recent worldwide development of B. thuringiensis-based microbial insecticides and insect-resistant transgenic plants, as well as a landmark discovery of par asp orin, a cancer cell-specific cytotoxin produced by B. thuringiensis. In this review, we describe examination of interaction between inclusion proteins of B. thuringiensis and brush border membrane of insects using a surface plasmon resonance-based biosensor, identification and characterization of parasporin-4, the latest parasporin produced by the B. thuringiensis A1470 strain, and an effective method for preparing the parasporin-4 from inclusion bodies expressed in the recombinant Escherichia coli cells.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.461-463
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• 2004

We investigate the role of secondary electrons in galaxy clusters and in ultra-luminous infrared galaxies (ULIGs). The radio emission in galaxy clusters and ULIGs is believed to be produced by the synchrotron radiation of relativistic electrons. Nonetheless, the sources of these relativistic electrons are still unclear. Relativistic secondary electrons can be produced from the hadronic interactions of cosmic-ray nuclei with the intra-cluster media (ICM) of galaxy clusters and the dense molecular clouds of ULIGs. We estimate the contribution of the secondary electrons in galaxy clusters and ULIGs by comparing observational results with theoretical calculations for the radio emission in these sources. We find that the radio halos of galaxy clusters can not be produced from the secondary electrons; on the other hand, at least for some ULIGs, the radio emission can be dominated by the synchrotron emission of the secondary electrons.

• Journal of Animal Environmental Science
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• v.4 no.1
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• pp.37-45
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• 1998

There are a lot of trace gas of gaseous pollutants produced from farm animals. CO2 and CH4 are gases produced directly by the animal. NH3, N2O are produced from animal waste. Most of the effects of these gaseous pollutants on the farm animals have not been investigated in detail. CO2 emission from animal is very little. CH4 release from ruminant is also considered to be a significant factor in potential global warming. Nitrous oxide (N2O) emissions could be avoided by using organic or mineral fertilizer only as much as is needed by plant growing. This paper gives an overview about problems and solving strategies for possibilities for reduction of gaseous pollutants. The way to reduce the gaseous pollution risks from livestock systems are discussed.

• Microbiology and Biotechnology Letters
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• v.27 no.6
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• pp.458-465
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• 1999

Streptomyces luteogriseus KT-10 isolated from Korean farm soil produced a strong cathepsin B inhibitor. Optimal conditions for the cathepsin B inhibitor production by s. luteogriseus KT-10 were evaluated. The cathepsin B inhibitor was produced with maximal yield in the cultural condition of pH 7.0 and $25^{\circ}C$ for 4 days. Optimal medium for the cathepsin B inhibitor production was determined to be a medium containing 20g, peptone 3g, yeast extract 1g, K2HPO4 0.5g, MgSO4.7H2O 0.5g, NaNO3 0.5g, NaCl 0.5g per l. The cathepsin B inhibitor produced by S. luteogriseus KT-10 could also inhibit the other proteinases such as trypsin, papain, and cathepsin D.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.405-407
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• 2009

A Bacillus subtilis mannanase gene was subcloned into an Escherichia coli- Corynebacterium lactofermentum shuttle vector pHE83, and the resultant plasmid pHE83M was transferred into an endogenous plasmid-free strain of C. lactofermentum. Mannanase produced by the recombinant C. lactofermentum (pHE83M) was secreted extracellulary at the level of 86%, and the remaining activity of mannanase was detected in the cell-free extract. The maximum mannanase productivity of the recombinant strain reached 8.1 unit/mL in the culture filtrate of LB medium. According to the zymogram of mannanase on SDS-PAGE, it was found that the mannanase produced by the recombinant C. lactofermentum could be maintained stably with a migration identical to the mannanase produced by the parental strain, B. subtilis WL-3.

• Microbiology and Biotechnology Letters
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• v.19 no.4
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• pp.413-418
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• 1991

When L, bulgurzcus KFCC 35462 and S. uvarum KFCC 32021 were mixed cultured in soymilk, gorwth of L. bulgaricus was stimulated with growth of S. uvarunz little affected. Cultured in soymilk singly, L. bulgaricus produced only 0.07%) of acids. S. uvarum, cultured singly, produced 0.40% of ethanol and 0.18% of acids. Mixed culture of both produced 0.27% of acids and 0.42% of ethanol. Thus. S. uvarurrz was not much affected in growth and ethanol fermentation by L. bulgariccus, while L, bulgarzcus was stimulated by Sacch. uvarunz in growth but not in acid fermentation.