• Journal of the Korean Chemical Society
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• v.59 no.3
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• pp.225-232
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• 2015

A liquid chromatography-electrospray ionization-tandem mass spectrometry method (LC-ESI-MS/MS) was used for determining seven pesticides (2,4-dichlorophenoxyacetic acid, methomyl, aldicarb, 2-methyl- 4-chlorophenoxy- acetic acid, molinate, carbaryl and carbofuran) and two synthetic materials (quinoline and bisphenol-A) in surface water. The analytes were extracted using solid-phase extraction (SPE). The eluate was concentrated by nitrogen gas. 100 microliters of 30% (v/v) methanol aqueous solution were used to dissolve the residue and an aliquot of the reconstituted solution was directly injected into LC-ESI-MS/MS after the filtration using 0.2 μm polytetrafluoroethylene (PTFE) syringe filter. Under the established condition, the calibration curves of the analytes were linear with correlation coefficients of above 0.997. The quantification limit was 0.002~0.011 μg/L and the relative standard deviations were less than 16.4%. In addition, accuracy was in the range of 84~107% and the recoveries were values between 56.2 and 98.6%. In this study, the developed method was applied to the analysis of real surface water samples.

• Korean Journal of Food Science and Technology
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• v.52 no.4
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• pp.409-414
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• 2020

In this study, we conducted a physiochemical property analysis using commercial faba bean flour (CFBF), faba bean flour (FBF), and faba bean starch (FBS). We observed that the FBS granules were elliptical and cracked on the surface. Moreover, FBS showed significantly lower solubility and apparent viscosity than FBF and CFBF. With respect to the pasting properties, FBS exhibited a peak viscosity of 1349.3 cP at 94.8℃ and a breakdown of 42.7 cP, whereas FBF and CFBF displayed no pasting properties. The FBS gelatinization enthalpy (12.9 J/g) was relatively high compared with the values obtained for FBF and CFBF (5.9 and 4.6 J/g, respectively). The FBS X-ray diffraction patterns showed a C-type pattern with peaks at diffraction angle (2θ) of 5.9°, 15.2°, 17.3°, and 23.1°, which were the same in FBF and CFBF with relatively low peak intensity. These results represent basic data for using faba bean as a food material.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.255-260
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• 1997

Glucomannan was isolated from konjac (Amorphophallus konjac) flour by precipitating in aqueous alcohol solution. Konjac glucomannan films were prepared at various concentrations up to 1.0% (w/v) in aqueous glycerol solutions. Tensile strength (TS), percent elongation (E), water vapor permeability (WVP) as the barrier property and the solubility of the films were varied with glucomannan concentrations, glycerol contents and storage humidities. TS was decreased as the glucomannan concentration in the film and relative humidity for storage increased, and E was vice versa. WVP showed better barrier properties compared with other polysaccharides films. Glycerol contents in the film significantly affccted TS and E, but did not affect WVP. The glucomannan films were completely dissolved in the water by 150 min stirring at room temperature.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.69-74
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• 2004

'Mixing' and 'immersion' $CaCl_{2}$ treatment methods were tested for preparation of bio-degradable films using powders of sea mustard (Undaria pinnatifida) (leaf, stem, and sphorophyll), sweet tanlge (Laminaria japonica), and fusiforme (Hizikia fusiforme) by extracting alginate through acid-alkali extraction method. Except fusiforme powder, flexible, free-standing films were produced by both methods using all marine algae powders tested. Except water solubility (WS), surface color, tensile strength (TS), elongation at break (E), and water vapor permeability (WVP) did not show distinct difference between $CaCl_{2}$, treatment methods. Although TS, WVP, and WS of marine algae powder films were lower than those of alginate films, they indicate potential in application as a new source of bio-degradable packaging materials.

• Journal of Life Science
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• v.19 no.6
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• pp.836-838
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• 2009

Tissue plasminogen activator (tPA) is very useful for dissolving the clots of blood, however, the use of tPA is limited to only 3-5% of ischemic stroke patients because of the narrow therapeutic time windows and negative side effects. Previous evidences suggest that limitation of tPA in thrombolytic therapy may be related to the upregulation of MMPs. However, little is known about the regulatory mechanism. In this study, we examined the role of tPA on MMP upregulation in rat neuronal cells. tPA (5 ${\mu}g$/ml) increased MMP-9 levels of neuronal cells in a time dependent manner. Hypoxia/reoxygenation amplified tPA-induced MMP-9 levels significantly. Pretreatment with JNK inhibitor SP600125 reduced the MMP-9 response. These results suggest that tPA can upregulate MMPs in neuronal cells and that JNK kinase may be involved.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.2
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• pp.167-175
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• 2005

Houttuynia cordata THNUB (He; Uh-Sung-Cho) is a medicinal plant which has been widely used as a component of blood-building decoctions. This study was performed to investigate the immunomodulative effect of He in mice. In vitro experiment, the mice splenocytes proliferation and three kinds of cytokines (IL-1$\beta$, IL-6, TNF- $\alpha$) production by mice peritoneal macrophages cultured with six (methanol, hexane, chloroform, ethylacetate, butanol and water) fractions of He were used to indicate the immunomodulative effect. Ex vivo experiment, the different concentrations of He water extract was orally administrated every other day for two weeks. The production of cytokines IL-1$\beta$, IL-6, TNF- $\alpha$) secreted by activated macrophages and the mice splenocytes proliferation were used as an index for the immunocompetence. The supplementation of all six fractions of He enhanced the splenocytes proliferation at the level of 6.58$\pm$1.23∼47.82$\pm$5.48 compared to that of control in the range of 1∼50 $\mu\textrm{g}$/mL. IL-1$\beta$ production was significantly increased with the supplementation of chloroform and water extract of He. Higher level of IL-6 production was detected by the supplementation of ethylacetate, butanol and water extract. TNF - $\alpha$ production was enhanced by the supplementation of all six fractions of He. From the ex vivo study, the highest proliferation of splenocytes was seen from the mice orally administrated with the He water extract at the concentration of 500 mg/kg bw In case of cytokines production, IL-1$\beta$, IL-6, and TNF- $\alpha$ release by activated peritoneal macrophages were augmented by the oral administration of He water extract. These results indicated that He may enhance the immune function by regulating the splenocytes proliferation and cytokines production capacity in mice.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.423-429
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• 2008

Currently, Ash-free clean coal producing process by solvent extraction is under development. The produced ash-free clean coal can be directly combusted in a gas turbine which results in substantial improvement of power generation efficiency. However, the clean coal produced by the solvent extraction still contain trace amount of alkali metal which may cause corrosion on turbine blades during the direct combustion. In present work ${\alpha},{\beta}$-metal (Zr and Ti) phosphates and H-Y zeolite were synthesized and their ion exchange characterizations were investigated for the application on alkali metal removal for clean coal production. $Na^+$ ion removal capacities of the metal phosphates and H-Y zeolite were measured and compared in both aqueous solution (100 ppmw, $Na^+$) and coal dissolved N-methyl-2-pyrrolidone (NMP, 12 ppmw $Na^+$) at elevated temperature. In aqueous solution, the ${\beta}$ form metal phosphates showed very high ion exchange capacities compared to ${\alpha}$ form. ${\beta}$ form metal phosphates also showed higher $Na^+$ removal capacities than H-Y zeolite. In ion exchange medium of NMP, all the ${\alpha}$ form metal phosphates showed over 90% of $Na^+$ ion removal efficiency in the temperature range of 200 to 400 while that of H-Y zeolite decreased as a half when the temperature was over 350. In addition, the regenerated metal phosphates by acid treatment showed no sign of degradation in $Na^+$ removal efficiency. Among the metal phosphates used, $Zr_{0.75}Ti_{0.25}(HPO_4)_2$ showed the best performance in $Na^+$ removal and is expected to be the most suitable inorganic ion exchanger for the alkali metal removal process.

• Economic and Environmental Geology
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• v.36 no.1
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• pp.27-38
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• 2003

Arsenic contamination around Au-Ag mining areas occurs mainly from the oxidation of arsenopyrite which is frequently contained in mine tailings. In weathered tailings, oxidation of sulfide minerals typically results in the formation of abundant ferric (oxy)hydroxides or (oxy)hydroxysulfates near the tailings surface, and arsenic may be associated with these secondary precipitates. In this study, solid phases of arsenic in weathered tailings of some Au-Ag mines were investigated through the SEM/EDS and sequential extraction analyses. The stability of As solid phases and the leaching potential were assessed with the variation of pH and Eh conditions. Oxidation of sulfides in the tailings samples was indicated by depletion of S molar concentrations compared to As and heavy metals. Under XRD examinations, jarosite as an Fe-oxyhydroxysulfate was found in the tailings of Deokeum, Dongil and Dadeok, and scorodite as an As-bearing crystalline mineral was identified from Dadeok which has the highest concentration of As (4.36 wt.%). Beudantite-like phases and some Pb-arsenates were also found under SEM/EDS analysis, and most of As phases were associated with Fe-(oxy)hydroxides and (oxy)hydroxysulfates despite a few arsenopyrite from Samgwang and Gubong. Sequential extraction analysis also showed that As was present predominantly as coprecipitated with Fe hydroxides from Dongil, Dadeok and Myungbong (72∼99%), and as sulfides (58%) and Fe hydroxide-associated forms (40%) from Samgwang and Gubong. In the tailings leaching experiment, As was released with high amounts by the dissolution of As-bearing Fe(oxy)hydroxysulfates in the lowest pH (2.7) conditions of Deokeum, and by desorption under alkaline conditions of Samgwang and Gubong. Higher leaching rates of arsenite(+3) were found under acidic conditions, which pose a higher risk to water quality. Changes in pH and Eh conditions coupled with microbial processes could influence the stabilities of the As solid phases, and thus, time amendments or landfilling of weathered tailings may result in enhanced As mobilization.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.2
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• pp.171-181
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• 2018

Genistein is one of the representative isoflavone compounds isolated from soybeans and has been studied very well for its anti-aging and anti-inflammatory activity through previous studies. However, although genistein exhibits high solubility in organic solvents, it shows low bioavaility due to the low water solubility. In this study, we compared directly the functional difference between genistein and genistein cyclodextrin complex which has the improved water solubility and stability by cell based assay. Cell cytotoxicity experiment were carried out on RAW264.7 with CCK-8 assay and cytotoxicity was appeared from $10{\mu}g/mL$, thereby maximum concentration was set to $10{\mu}g/mL$ in all condition. We discovered that genistein CD complex suppressed NO production and iNOS expression as concentration dependent manner in the condition of LPS rather than genistein. Also, we could understand that genistein CD complex was able to down-regulate mRNA expression of anti-inflammatory cytokines such as $IL1-{\alpha}$, $IL1-{\beta}$, IL-6, and $TNF-{\alpha}$ as concentration dependent manner in the presence of LPS. In addition, we verified that genistein CD complex increased TEER of HaCaT human keratinocyte cells as concentration dependent pattern and stimulated cell division and migration rather than genistein in cell migration assay. Thus, it is expected that it can be used as an effective cosmetic raw material for improving atopic dermatitis or skin barrier if clinical studies on skin regeneration and skin barrier of the genistein CD complex are carried out.