• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.227-233
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• 1996

Tyrosinase is an enzyme which catalyzes an enzymatic browning of some foods and in vivo synthesis of melanin. In order to produce natural and edible inhibitor of the enzyme which is expected to have whitening effect on melanogenesis, a microorganism was selected from fermented foods. It was named as NU-7, and cultured in mushroom (Lentinus edodes, Shiitake) media. Optimal media to produce tyrosinase inhibitor was formulated by varing nitrogen or carbon content. If glucose content was in a range of 3-20% and ammonium sulfate was in a range of 0-0.25%, production of inhibitor was independent of cell mass. Addition of ammonium sulfate as a nitrogen source had little effect on inhibitor production. Production of inhibitor (Y) was proportionally related to shiitake content (X) with a regression equation of Y= -0.96X$^{2}$ + 13.07X + 14.43 (R = 0.96). These results indicate that shiitake and glucose are necessary for the production of tyrosinase inhibitor. In the analysis of mycotoxin in culture broth, aflatoxin was not detected, suggesting that it would be probably edible.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.682-688
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• 1999

We threat sludge by heating methods with low pollution and high efficiency. Organic and inorganic components in Sludge can be almost removed through the heaging treatment process, and thefinal products are called artifical aoil or artificial media which are depended on temperature control. It can be recycled on the agricultural sites. Because it contained sort of organic matters while high heaging process with addition. To use them as agricultural materials, it need to know their characteristic transform in the nature. So we have planting bean and corn for two years with standard planting methods and to anticipate changing characteristics of artificial media and artificial soil by staying it natural condition, analyze it physical and chemical characteristics. This study will be contributed to reduce mass enviornmental problems by the treatment of Sludge and make it possible application for a agriculture use.

• Korean Journal of Organic Agriculture
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• v.8 no.1
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• pp.101-109
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• 1999

In order to investigate the possibility of treating the different mixture ratios of apple pomace and nightsoil sludge by vermicomposting was performed and the stability of worm casts, and availability of worm casts as plant growth media was evaluated by the analysis of chemical composition. The results were obtained as follows ; 1. The value of cast production at 100% apple pomace treatment was higher than those of other mixture ratios of apple pomace and nightsoil sludge. 2. The highest values of increasing rate and reproductive efficiency were obtained at mixture ratios of 60% apple pomace with 40% nightsoil sludge. 3. The value of increasing rate at 100% nightsoil sludge treatment was lower that those of other mixture ratios of apple pomace and nightsoil sludge. 4. Organic matter, available inorganic nutrients and stability of worm casts showed high values in all treatments. It means that worm casts are an excellent plant growth media source with a high chemical composition and their stability.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2377-2381
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• 2007

Solvolyses of 3,4-dimethoxybenzenesulfonyl chloride (DSC) in water, D2O, CH3OD, and in aqueous binary mixtures of acetone, acetonitrile, 1,4-dioxane, ethanol, methanol, and 2,2,2-trifluoroethanol (TFE) have been investigated at 25.0 oC. Kinetic solvent isotope effects (KSIE) in water and in methanol and product selectivities in alcohol-water mixtures are also reported. The Grunwald-Winstein plot of first-order rate constants for the solvolyic reaction of DSC with YCl shows marked dispersions into separated lines for various aqueous mixtures. With use of the extended Grunwald-Winstein equation, the l and m values obtained are 1.12 and 0.58 respectively for the solvolyses of DSC. The relatively large magnitude of l is consistent with substantial nucleophilic solvent assistance. From Grunwald-Winstein plots the rate data are dissected approximately into contributions from two competing reaction channels. This interpretation is supported for alcohol-water mixtures by the trends of product selectivities, which show a maximum for ethanol-water mixtures. From the KSIE of 1.45 in methanol, it is proposed that the reaction channel favored in methanolwater mixtures and in all less polar media is general-base catalysed and/or is possibly (but less likely) an addition-elimination pathway. Also, the KISE value of 1.35 for DSC in water is expected for SN2-SN1 processes, with minimal general base catalysis, and this mechanism is proposed for solvolyses in the most polar media.

• Korean Journal Plant Pathology
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• v.13 no.4
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• pp.225-231
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• 1997

Activities of polygalacturonase, laccase, and intra- and extra-cellular $\beta$-glucosidase produced by 20 Botrytis cinerea isolates in liquid culture media containing cucumber cell was as a carbon source were measured and their relationships to the pathogenicity were analyzed. No significant correlations between these enzyme activities and the pathogenicity of B. cinerea were found. Mycelial growth rate on Bayendamm media, however, was higthly correlated with the pathogenicity (r=0.522) anong these isolates. Immuno-blot analysis of the culture filtrate using antibody against against exo-polygalacturonase revealed that only one band with molecular weight of 66 kDa was detected amone 34 tested isolates. It appears that these enzymes may not be primary factors in dermining the pathogenicity of B. cinerea.

• Korean Journal of Environmental Biology
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• v.29 no.1
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• pp.1-10
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• 2011

Amphibian population declines globally. Aquatic contamination by organic pollutants including endocrine disrupters has been suspected to the one of the reason for distinction of amphibia which has obligate aquatic life style during larval period. Amphibians have been widely accepted as animal model for the study of endocrine disruption in aquatic ecosystem at molecular as well as individual levels. There are increasing need for toxicological data in amphibians at multiple endpoints for management of contamination and development of safety guideline for important EDs in aquatic media. Alkylphenols have been widely used in agricultural, industrial, and housekeeping activities, contaminating the aquatic media and evoking endocrine disruption in aquatic animals. In this review, we summarized data concerning the endocrine disruption by alkylphenol organic pollutants on amphibians according to route, concentration, terms, and developmental stage of exposure together with mechanism of endocrine disruption.

• Journal of Microbiology and Biotechnology
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• v.27 no.7
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• pp.1242-1248
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• 2017

Several medicinal plants are ethnomedically used in Korea as agents for treating infection, anti-inflammation, and pain relief. However, beyond typical inhibitory effects on cell growth, little is known about the potential anti-biofilm activity of these herbs, which may help to prevent cavities and maintain good oral health. This study aimed to investigate the antimicrobial and anti-biofilm activities of the methanol extracts of 37 Korean medicinal plants against dental pathogens Streptococcus mutans and Candida albicans, which synergize their virulence so as to induce the formation of plaque biofilms in the oral cavity. The antimicrobial activities were investigated by broth dilution and disk diffusion assay. The anti-biofilm and antioxidant activities were evaluated based on the inhibitory effect against glucosyltransferase (GTase) and the DPPH assay, respectively. Among 37 herbs, eight plant extracts presented growth and biofilm inhibitory activities against both etiologic bacteria. Among them, the methanol extracts (1.0 mg/ml) from Camellia japonica and Thuja orientalis significantly inhibited the growth of both bacteria by over 76% and over 83% in liquid media, respectively. Minimum inhibitory concentration (MIC) values of these methanol extracts were determined to be 0.5 mg/ml using a disk diffusion assay on solid agar media. Biofilm formation was inhibited by more than 92.4% and 98.0%, respectively, using the same concentration of each extract. The present results demonstrate that the medicinal plants C. japonica and T. orientalis are potentially useful as antimicrobial and anti-biofilm agents in preventing dental diseases.

• Korean Journal of Environmental Agriculture
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• v.19 no.2
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• pp.122-127
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• 2000

A stream purification system was applied to the upper reaches of the Masan Reservoir to improve the water quality. This system consisted of two channels which were constructed on both sides of the stream, one side packed with crushed gravels and the other with plastic filter media. The system operated under low pollutant concentrations and high hydraulic loadings during a dry season to avoid clogging of the filter media. Removal rate and efficiency of chemical oxygen demand (COD) in the channel packed with crushed gravel were $14.8g/m^3/d$ and 11.5%, and for the channel with plastic filter media, $50.1g/m^3/d$ and 13.5%, respectively. Removal efficiencies of total phosphorus (T-P) were 6.6% (gravel) and 10.0% (plastic media). These results indicated plastic filter media having relatively high specific surface areas were more efficient than crushed gravels in removing pollutants. However, due to low influent water quality during dry season, the removal efficiencies were low. The proportion of nitrate nitrogen to total nitrogen (T-N) of the inflow was high but, as the system operated under aerobic condition, nitrate nitrogen could not denitrified. Accordingly, total nitrogen was not attenuated with this system. To improve the reservoir water quality effectively, this system should be able to treat the storm runoff containing higher pollutant loadings. When the filter materials are clogged by the storm runoff instead of backwashing, it would be more efficient to replace them, Therefore, the use of natural materials which are light, easily obtaining and replaceable, and have high specific surface areas is recommended.

• Bulletin of the Korean Chemical Society
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• v.12 no.4
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• pp.454-455
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• 1991

• Journal of Satellite, Information and Communications
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• v.9 no.1
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• pp.6-12
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• 2014

The traditional broadcasting service has advanced into a smart media service with the help of communication network. in In the smart media ecosystem, a variety of innovative media services have been provided by new players. However, terrestrial broadcasting service companies seem to lag comparatively behind new players in spite of their powerful contents production capacity and stable terrestrial media delivery networks. In this paper, we design a proposed media platform based on a set-to-box (STB) with various new function for terrestrial ultra-high definition(UHD) broadcasting service. Also we suggest specific transmission network architecture and platform components for UHD broadcasting service. The proposed media platform is expected to increase the number of direct home reception and to enhance the right of the free-viewers which is one of the natural mission of terrestrial broadcasting company. Also it can provide some profit model of UHD terrestrial broadcasting service with new value-added services.