• Korean Journal of Environmental Biology
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• v.26 no.2
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• pp.102-108
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• 2008

Many alternative biocidal additives were applied to antifouling paint to replace TBT, and Sea-Nine 211 is one of alternating organic booster compounds used in antifouling paint. In this study, extent of Sea-Nine 211 toxicity on marine benthic bivalve is evaluated. Sea-Nine 211 was injected to surf clam, Pseudocardium sachalinensis, that inhabitate northern part of Gangwon Province, Korea. Survival rate of the clam and xenobiotics metabolizing enzyme activities in digestive gland were measured during 4 day-exposure period. The results were compared with those of TBT exposed clam. There were no mortality of clam in the solvent (DMSO) control group and the three Sea-Nine 211 exposure groups (5, 25, 50 mg kg$^{-1}$ body weight), while the clam exposed to 1, 2 and 5 mg kg$^{-1}$ TBT chloride (TBTC) demonstrated 70, 30 and 0% survival rate, respectively. The Sea-Nine 211 exposure group showed a tendency of cytochrome P450 (CYP) induction according to the exposure duration, on the other hand, CYP content was decreased in the TBT exposure group. NADPH cytochrome P450 reductase activity slightly increase according to the exposure duration in the Sea-Nine 211 exposure group, while TBTC inhibit its activity as CYP content. Moreover, there was no significant change of NADH cytochrome b5 reductate activity in the clam epxosed to Sea-Nine 211. In the TBTC exposure group, its activity increased in early exposure period and then significantly decreased the rest of exposure period. All the results indicate that Sea-Nine 211 demonstrated a tendency to induce CYP level, while TBTC inhibits the CYP level, NADPH cytochrome P450 reductase and NADH cytochrome b5 reductase activities.

• Clean Technology
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• v.17 no.4
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• pp.285-299
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• 2011

As one of the REACH obligations, the extended safety data sheet (eSDS) should be communicated within the supply chain under the REACH Regulation. Based on technical guidance documents published on the ECHAs website and survey of EU's recent REACH-related informations, this paper includes a study on details of how to develop exposure scenarios (ES) such as structure of ES, process of ES develpoment, standard workflows and key input data to develop ES with an introduction of eSDS concept. This paper also contains an overview on operational conditions (OCs) and risk management measures (RMMs) that are what to consider when building an ES. The structure of Chesar (Chemical Safety Assessment and Report tool) developed by European Chemicals Agency (ECHA) is studied with a review of the available exposure estimation tools for workers, environment and consumers. Case example of generic exposure scenario (GES) for organic solvent is presented. To guide Korean EU-exporting companies, their participating roles in three steps of preparing ES are addressed.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.564-570
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• 1995

N-Benzoyl-L-aspartyl-L-phenylalanine methyl ester(BzAPM), a novel aspartame precursor, was investigated for its enzymatic synthesis by immobilized thermolysin using a water-miscible organic solvent system. The substrate used were N-benzoyl-L-aspartic acid(BzAsp) and L-phenylalanine methyl ester (PheOMe). Synthetic conditions such as substrates concentration, temperature, pH, and some metallic ions were varied to study their effects on BzAPM synthesis. The synthetic reaction rate increased linearly as the PheOMe concentration increased at a constant concentration of BzAsp(100 mM), and the maximum reaction rate was obtained at BzAsp concentration of 200 mM when 300 mM PheOMe was used. The optimum pH and temperature were found to be 6.1 and $40^{\circ}C$, respectively. The metallic ions such as $Zn^{2+},\;Mg^{2+},\;Mn^{2+},\;Fe^{2+},\;Pb^{2+}\;and\;Cu^{2+}$ at 5 mM level showed inhibitory effect on BzAPM synthesis, while $Co^{2+}$ and $Ca^{2+}$ ion increased synthesis. $Co^{2+}$ ion was also found to have synergistic effect with $Ca^{2+}$ ion. Benzoic acid, L-phenylalanin and NaCl showed inhibitory effect.

• Journal of Adhesion and Interface
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• v.12 no.2
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• pp.47-55
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• 2011

UV-curable coatings have been used in various industries due to their advantages such as high mechanical property, good solvent resistance, fast curing process and low volatile organic compounds. However, a lack of flexibility of UV-cured films is a weak point for the pre-coated system of roll-to-roll process. In this study, UV-curable polycarbonate-based methacrylates were synthesized with polycarbonate diol, isophorone diisocyanate and 2-hydroxyethylmethacrylate to improve flexibility of the UC-cured films. The effects of polyol molecular weight, content of photoinitiator and monomers on the UV-curing behavior, flexibility and properties were investigated. The UV-curing behavior was measured by a photo-DSC, the pendulum hardness, tensile strength, viscoelastic properties were also evaluated.

• Clean Technology
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• v.25 no.2
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• pp.140-146
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• 2019

Flammable substances, such as organic solvents, are commonly used in laboratories and industrial processes. The flash point of flammable liquid mixtures is a very important parameter for characterizing the ignition and explosion hazards, and the flash points of mixtures of $C_2{\sim}C_3$ alcohols and 2,2,4-trimethylpentane were measured in the present study. The 2,2,4-trimethylpentane is an important component of gasoline and is frequently used in the petroleum industry as a solvent. Lower flash point data were measured for the binary systems {ethanol + 2,2,4-trimethylpentane}, {1-propanol + 2,2,4-trimethylpentane}, and {2-propanol + 2,2,4-trimethylpentane}. The flash point measurements were carried out according to the standard test method (ASTM D3278) using a Stanhope-Seta closed cup flash point tester. The measured flash points were compared with the predicted values calculated using Raoult's law and also following $G^E$ models: Wilson, Non-Random Two Liquid (NRTL) and UNIversal QUAsiChemical (UNIQUAC). These models were able to predict the experimental flash points for different compositions of {$C_2{\sim}C_3$ alcohols + 2,2,4-trimethylpentane} mixtures with minimal deviations. The average absolute deviation between the predicted and measured lower flash point was less than 1.28 K. A minimum flash point behaviour was observed in all of the systems as in the many observed cases for the hydrocarbon and alcohol mixtures.

• Journal of Life Science
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• v.28 no.12
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• pp.1438-1447
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• 2018

We investigated the anti-inflammatory activities of various organic solvent extracts with and without Lactobacillus plantarum fermentation of Aralia continentalis Kitagawa which has hypotensive effects in addition to excitatory effects on the central nervous system. It has been used to treat arthritis, colds, neuralgia, rheumatism, and itchy skin. Our extracts were tested for their anti-inflammatory potential on NO production and the expression of inflammatory factors in lipopolysaccharide-stimulated RAW264.7 macrophages. Extracts with and without L. plantarum fermentation were prepared using water, ethanol, hexane, ethyl acetate, and butanol. The RAW264.7 cells were tested for toxicity and the anti-inflammatory activity of each extract was determined at a concentration with no toxicity to the cells. The extracts used in this study significantly inhibited both the production of NO and the mRNA expression of COX-2 and iNOS, the major inflammatory factors. The production of inflammation-related cytokines $IL-1{\beta}$, IL-6, and $TNF-{\alpha}$ was also significantly reduced. These results suggest that the extracts involving fermentation by L. plantarum can inhibit cytokines by controlling the expression of inflammatory cytokine genes. It is considered that the water, ethanol, and butanol extracts after fermentation with L. plantarum could be useful as functional natural materials with anti-inflammatory effects.

• Design & Manufacturing
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• v.13 no.2
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• pp.30-36
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• 2019

Traditional cell culture(2-dimensional) is the method that provide a nutrient and environment on a flat surface to cultivate cells into a single layer. Since the cell characteristics of 2D culture method is different from the characteristics of the cells cultured in the body, attempts to cultivate the cells in an environment similar to the body environment are actively proceeding in the industry, academy, and research institutes. In this study, we will develop a technology to fabricate micro-structures capable of culturing cells on surfaces with various curvatures, surface shapes, and characteristics. In order to fabricate the hemispheric plastic structure(thickness $50{\mu}m$), plastic preform mold (hereinafter as "preform mold") corresponding to the hemisphere was first prepared by injection molding in order to fabricate a two - layer structure to be combined with a flat plastic film. Then, thermoplastic polymer dissolved in an organic solvent was solidified on a preform mold. As a preliminary study, we proposed injection molding conditions that can minimize X/Y/Z axis deflection value. The effects of the following conditions on the preform mold were analyzed through injection molding CAE, [(1) coolant inlet temperature, (2) injection time, (3) packing pressure, (4) volume-pressure (V/P). As a result, the injection molding process conditions (cooling water inlet temperature, injection time, holding pressure condition (V / P conversion point and holding pressure size)) which can minimize the deformation amount of the preform mold were derived through CAE without applying the experimental design method. Also, the derived injection molding process conditions were applied during actual injection molding and the degree of deformation of the formed preform mold was compared with the analysis results. It is expected that plastic film having various shapes in addition to hemispherical shape using the preform mold produced through this study will be useful for the molding preform molding technology and cast molding technology.

• Journal of Life Science
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• v.18 no.11
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• pp.1499-1506
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• 2008

To examine antitumor activity of the edible plant Zanthoxylum schinifolium, the cytotoxic effect of various organic solvent extracts of its stems on human acute leukemia Jurkat T cells was investigated. Among these extracts such as methanol extract (SS-7), methylene chloride extract (SS-8), ethyl acetate extract (SS-9), n-butanol extract (SS-10), and residual fraction (SL-11), SS-8 exhibited the most cytotoxic activity against Jurkat T cells. The methylene chloride extract (SS-8) possessed the apoptogenic activity capable of inducing sub-G1 peak along with apoptotic DNA fragmentation in Jurkat T cells. Western blot analysis revealed that SS-8 induced apoptosis via mitochondrial cytochrome c release into cytoplasm, subsequent activation of caspase-9 and caspase-3, and cleavage of PARP, which could be blocked by overexpression of Bcl-xL. Jurkat T cell clone I2.1 $FADD^{-/-}$) and Jurkat T cell clone I9.2 (caspase-$8^{-/-}$ were as sensitive as was the wild-type Jurkat T cell clone A3 to the cytotoxic effect of SS-8, suggesting no contribution of Fas/FasL system to the SS-8-mediated apoptosis. The GC-MS analysis of SS-8 showed that it was composed of 16 ingredients including 9,12-octadecanoic acid (18.62%), 2,4-dihydro-5-methyl-4- (1-methylethylidene)- 2-(4-nitrophenyl)-3H- pyrazol-3-one (14.97%), hexadecanoic acid (14.23%), (z,z)-6,9-pentadecadien- 1-ol (13.73%), 5,6-dimethoxy-2-methyl benzofuran (10.95%), and 4-methoxy-2-methylcinnamic acid (5.38%). These results demonstrate that the methylene chloride extract of the stems of Z. schinifolium can induce apoptotic cell death in Jurkat T cells via intrinsic mitochondria-dependent caspase cascade regulated by Bcl-xL without involvement of the Fas/FasL system.

• Journal of Preventive Medicine and Public Health
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• v.31 no.4 s.63
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• pp.692-707
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• 1998

Aim. A neurobehavioral test for workers exposed to organic solvents in the workplace can be affected by many factors : age, education, motivation, ethnicity, etc. To apply more suitable neurobehavioral test for Korean workers, we evaluated the validity of several items of computerized and traditional neurobehavioral tests. Methods. We have applied eleven tests : four items of computerized neurobehavioral test(Swedish Performance Evaluation System) including Addition, Symbol-Digit, Dig-it Span, and Finger tapping speed, and seven items of traditional neurobehavioral test consisting of Addition, Digit-Symbol, Digit Span, Benton visual retention test, Pursuit aiming, Pegboard, and Tapping. These tests were performed on 96 workers exposed to solvents, and 100 reference workers. The concurrent and construct validities were evaluated by group difference, correlation with age, educational level, hippuric acid level, neurotoxic symptom, current exposure level, multitrait-multimethod matrix, fator analysis, and discriminant analysis. Results. Statistically significant differences were observed between the workers exposed to solvents and referents in computerized Symbol-Digit, Finger tapping speed, traditional Digit-Symbol and Pegboard. The computerized Symbol-Digit, traditional Digit-Symbol, Addition, Benton visual retention test, and Pegboard were found to be related to the age. The performance of computerized Symbol-Digit, Addition, and traditional Digit-Symbol were found to be related to the educational level significantly. The computerized Symbol-Digit, Finger tapping speed, and traditional Digit-Symbol were found to be related to hippuric acid, and neurotoxic symptom. The discriminability of Finger tapping speed, and Pegboard was better than the other tests. In discriminant analysis, the model with two variables, the computerized Symbol-Digit and Pegboard, classified almost 70 percent of the workers correctly. Conclusions. These results suggest that the computerized Symbol-Digit, Finger tapping speed, and Pegboard are more satisfactory for our purpose, and the Addition, Tapping, Benton visual retention test, and Pursuit aiming are less valid than other items. These may allow the reasonable selection of core neurobehavioral tests for workers exposed to solvents in Korea.

• Korean Journal of Food Science and Technology
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• v.49 no.3
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• pp.304-310
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• 2017

The aim of this study was to compare the physicochemical properties of domestic and imported commercial plain wheat flour and dough. Four types of domestic wheat flour (DW; DW1-4) were compared to four types of imported wheat flour (IW; IW1-4). DWs exhibited lower moisture content, lightness (L), and whiteness, and higher protein content, redness (a), and yellowness (b), than those exhibited by IWs. Solvent retention capacity of DWs and IWs was similar; however, DWs showed higher gluten performance index. Pasting properties, analyzed by rapid visco analyzer (RVA), were similar for DW1, DW2, and IWs; however, DW3 and DW4 showed different RVA patterns. Considering that DW3 and DW4 were organic wheat flour, possible incorporation of damaged kernel might increase amylase activities resulting in decreased peak viscosity. Dough resistance (108.4-159.9 g) and extensibility (11.8-16.7 mm) of IWs were higher than those of DWs (78.0-118.7 g, 8.7-12.5 mm, respectively).