• Journal of Life Science
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• v.9 no.1
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• pp.99-105
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• 1999

The aims of this studies were carried out to investigate the antioxidant activity on low density lipoprotein(LDL) using substances extracted from Bacillus sp. RH-5. The antioxidative substances produced extracellular in the culture broth by Bacillius sp. RH-S was obtained by elution of chloroform : methanol from silicagel column (80cm x100cm) chromatography. Band 4 eluted from fraction 3 by TLC was appeared at highest level of antioxidative activity using thiocyanate methed. Band 4 at a concentration of 100 or 200$\mu$g/$m\ell$ inhibited oxidation of LDL induced by the mouse transformed macrophage. According to IR. NMR or GC/MASS, the antioxidant substance was identified as 5-hydroxyindole.

• Steel and Composite Structures
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• v.32 no.3
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• pp.411-422
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• 2019

Six shear-critical square tubed steel reinforced concrete (TSRC) columns using the high-strength concrete ($f_{cu,150}=86.6MPa$) were tested under constant axial and lateral cyclic loads. The height-to-depth ratio of the short column specimens was specified as 2.6, and the axial load ratio and the number of shear studs on the steel shape were considered as two main parameters. The shear failure mode of short square TSRC columns was observed from the test. The steel tube with diagonal stiffener plates provided effective confinement to the concrete core, while welding shear studs on the steel section appeared not significantly enhancing the seismic behavior of short square TRSC columns. Specimens with higher axial load ratio showed higher lateral stiffness and shear strength but worse ductility. A modified ACI design method is proposed to calculate the nominal shear strength, which agrees well with the test database containing ten short square TSRC columns with shear failure mode from this study and other related literature.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.3
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• pp.332-340
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• 2007

Storm runoff from road contains significant loads of particulate and dissolved solids, organic constituents and metal elements. Micro particle is important when considering pollution mitigation because pollutant metal and organics have similar behavior with particles. The objective of this research is to evaluate the hydrodynamic filter separator performance for road storm runoff treatment. A various types of media such as perlite, granular activated carbon, zeolite were used for column test packing media and filter separator, and to determine the removal efficiency with various surface loading rate. As the results of column test, the highest SS removal efficiency was using mixed media(granular activated carbon, zeolite and perlite), and granular activated carbon mixed with zeolite has higher heavy metal removal efficiency than perlite. In laboratory scale hydrodynamic filter separator study, the operation ranges of surface loading rates were from 192 to 1,469 $m^3/m^2/day$. The estimated overall removal efficiencies of hydrodynamic filter separator for typical storm runoff were SS 48.1%, BOD 31.9%, COD 32.6%, TN 15.5%, and TP 17.3%, respectively. For the case of heavy metals, overall removal efficiencies were Fe 26.0%, Cu 19.4%, Cr 25.7, Zn 16.6%, and Pb 15.0%, respectively. The most appropriate medium for hydrodynamic filter separator was perlite mixed with granular activated carbon to treatment of road storm runoff.

• Journal of Life Science
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• v.13 no.1
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• pp.90-98
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• 2003

An allium rhizobacterium Serratia plymuthica AL-1 was previously selected as a biocontrol agent of allium white rot. The chitinase from S. plymuthica AL-1 produced in medium containing colloidal chitin was purified by ammonium sulfate precipitation (40~70%), affinity adsorption, column chromatography on DEAE-sephadex A-50 and sephadex C-200 gel filtration. The enzyme was purified 10.8-fold with a yield of 7.3% from the starting culture broth. The purified chtinase gave a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis, it's molecular weight was estimated to be 55 kDa. The optimum pH and temperature of the purified enzyme were pH 5.5 and $55^{\circ}C$, respectively and it is stable up to $50^{\circ}C$ and maintains around 90% of its activity for 60min. The enzyme were activated by $Ca^{2+}$, $Mn^{2+}$ and $Mg^{2+}$ and inhibited by $Cu^{2+}$, SDS, $\rho$-CMB, MIA, respectively. The purified chitinase showed broad spectrum of antifungal activities against plant pathogenic fungi Sclerotium cepivoruin, Alternana alternnta, Colletotrichum glceosporioidrs, Phoma sp., Sclerotinia sclerotiorum, Stemphylium solani, Fusarium oxysporium f. sp. niveum but rarely inhibited Phytophthora capsici and Pythium ultimum.. The purified chitinase from S. plymuthica AL-1 caused swelling, lysis, deceleration and degradation of the hyphal tips of S. sczerotiorum causing allium white rot. It suggest that S. prymuthica AL-1 chitinase play an important part in the bifunctional chitinase / lysozyme activity.

• Biomedical Science Letters
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• v.6 no.3
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• pp.209-221
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• 2000

The purpose of this study was to investigate the practical availability of pretense production that can be used at home after isolating Serratia sp.2000-1 which produced extracellular pretense from clinical specimen. Basic production conditions and partial enzymatic characteristics of pretense produced by Serratia sp. 2000-1 was as follows: The kind and concentration of carbohydrate, nitrogen and metal salts for optimal enzyme production condition were each identified as the concentration of 1.5% glucose, 2.0% CSP, and 0.1% CaCl$_2$, and the optimal temperature, time and initial pH for culture were each 3$0^{\circ}C$, 72 hours, and pH 8.0. The final enzymatic yeild that was purified by 3 steps with ammonium sulfate precipitation (45~80%), DEAE-cellulose column chromatography, and Sephadex G-200 gel chromatography was 14.4%, and enzyme inactivity rate increased approximately 291314s. The optimal temperature and pH for purified pretense activity were 35$^{\circ}C$ and pH 7.0~8.0, and purified pretense activity was relatively stable by 4$0^{\circ}C$ at pH 6~10 for 30 min, however heating at 6$0^{\circ}C$ for 30 min, it liminated detectable pretense activity. The pretense activity was activated by $Mg^{2+}$, $Ba^{2+}$, $Ca^{2+}$, Mn$^{2+}$, but inactiviaed by Hg$^{2+}$, Ag$^{2+}$, Cu$^{2+}$, and the pretense activity was inhibited strongly by SDS among enzyme activity inhibitors. Further study is required to evaluate the practical availability of pretense production that can be used at home by isolating Serratia sp. from more clinical specimen and examining pretense more in details.

• Journal of the Korean Geosynthetics Society
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• v.10 no.2
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• pp.35-43
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• 2011

Permeable Reactive Barriers (PRB) method is an economical method that does not require any other methods to be operated once it is installed as it controls of groundwater flow in the barrier, which is inserted a reactive material on the way of pollutant. The major dominant element of PRB is a reactive material in the reactive wall, and such factors as purification efficiency and used time based on the chemical and physical features in between the reactant and pollutant. High purification efficiency can be expected when a rational design that is synthetically considered in features of packing density, operation period, and adsorption reactant of pollutant. A column test was conducted for an application test using CFW as its adsorption reactant in order to remove copper($Cu^{2+}$) in the PRB system. The CFW was used for the reactant and selected inflow speed, density and thickness of PRB as its necessary factors for design of PRB. As a result of the experiment, the removal efficiency decreased as operating time of PRB increased and the efficiency linearly increased upon the length. Therefore, it is confirmed that the thickness of reactive materials in PRB system can be designed using the proposed formula considering purification time and density of CFW.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.231-237
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• 2006

The extracellular enzyme alginase produced by Bacillus licheniformis AL-577 was purified by ion chromatography on CM-Cellulose column, DEAE-Sepharose column, and followed by gel filtration on Sephadx G-100 column. The optimum pH and temperature for the activity of the purified enzyme were 6.0 and $35^{\circ}C$, respectively. The enzyme was stable at the pH range of $6.0\~9.0$ and at $20^{\circ}C$. The molecular weight of the enzyme was estimated to be about 25,500 daltons by SDS-polyacrylamide gel electrophoresis. NaCl was required for high activity of the enzyme. The enzyme was inhibited by $Ba^{2+},\;Co^{2+},\;Cu^{2+},\;Fe^{2+},\;Mg^{2+},\;Zn^{2+},\;NH_4^+$, EDTA, L-cysteine, and 2-mercaptoethanol, while stimulated by DTT, O-phenanthroline, $K^+$ and $Li^+$. This enzyme was proposed to be an alginase specifically degrading alginic acid.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.1
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• pp.57-62
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• 2008

No matter how small amount of heavy metals it may be cause skin allergies through percutaneous adsorption when existing in cosmetic products as impurities. In order to develop a highly sensitive method for simultaneous determination of $Pb^{2+},\;Fe^{2+},\;Cu^{2+},\;Ni^{2+},\;Zn^{2+},\;Co^{2+},\;Cd^{2+},\;and\;Mn^{2+}$ in coloring agents and cosmetic products with rapidity and accuracy, we carried out the determination on ion chromatography. All of these metals are well separated through a bifunctional ion-exchange column(IonPac CS5A) and detected by post-column reaction and spectrophotometric detection. The calibration graphs are linear($r^2>0.999$) in the range $0.1{\sim}1000{\mu}g/mL$. Detection limits for 200 ${\mu}L$ of sample solution are at the level of ${\mu}g/L$, which is sufficient for judging whether the product is safe or not. The relative standard deviations(RSDs) of the retention time and the peak area are less than 0.21 and 1.24%, respectively. The recovery rates are $97{\sim}104%$. The new method was applied to analyze the amount of heavy metals which were contained in 22 cosmetic products and 11 coloring agents.

• Applied Chemistry for Engineering
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• v.5 no.6
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• pp.1009-1015
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• 1994

Monodisperse porous poly(styrene-co-divinylbenzene)(St-DVB) gel and poly(acrylonitrile-co-ethylene dimethacrylate)(AN-EDMA) gel have been prepared by seed polymerization using polystyrene seeds, which were prepared by dispersion polymerization. The St-DVB and AN-EDMA gels had a narrow size distribution and pores suitable for packing materials of HPLC. The columns packed with these gels were proved to have high efficiency for GPC or HPLC coluuns. Adsorption properties of $Cu^{2+}$, $Cd^{2+}$ and ${UO_2}^{2+}$ ions on AAN-EDMA gel prepared from amidoximation of AN-EDMA gel were also determined.

• Journal of Life Science
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• v.8 no.5
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• pp.598-603
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• 1998

A marine microbe, Vibrio anguillarum was isolated from fish and studied for its concerning pathogenic substance of hemolysin. Purification of hemolysin was achieved by the procedure of ammonium sulfate precipitation from cul-ture filtrate, DEAE-cellulose chromatography, and G-200 gel filtration with 36 fold of purification and 2.3% yield. The molecular weight of the purified hemolysin was 38,000 dalton by SDS-PAGE. The purified hemolysin was stable at pH 6-9, below 45$^{\circ}C$, and up to 1% of NaCl, respectively. $Ca^{2+}, Cu^{2+}, Zn^{2+}, Fe^{2+}$ inhibited the hemolytic activity whereas EDTA and $Mg^{2+}$ did not.