• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.739-747
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• 1997

This study was performed to clarify various conditions on the test of lipoxygenase-l and to establish the application of new test method for varietal improvement of soybeans in order to decrease beany flavors. Potassium borate and Tris were used as buffer and O.1M potassium borate solution showed the best result for the lipoxygenase-l test. In the range of pH 8.5~9.0 of the buffer, 2mM linoleic acid as substrate was effective. For color development, 100$\mu$l of two solutions(KI and starch) were added to the half soybean seed, successively. The substrate solution included linoleic acid was stored safely for 10 days at 4$^{\circ}C$ in refrigerator and for 4 days at room temperature. The best result was as follows; the 1ml of substrate solution[0.1M potassium borate(pH 9.0), 0.1％ Tween-20, 2mM linoleic acid] was added to the chipped half soybean seed in l.5ml plastic tube, waited for 15 minutes, and 100$\mu$l of color development solutions(5％ saturated KI in 15％ acetic acid, 1％ starch) were added to the tube, successively. After 4 hours, the purple color was observed in the upper phase of the plastic tube in the presence of lipoxygenase-1 and milky color in absence of lipoxygenase-1. The purple color was stable from 4 to 24 hours. There was no interfering effect by lipoxygenase-2 and -3. The plastic tube should be placed in the tube stand without shaking during the lipoxygenase-l test.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.12
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• pp.667-675
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• 2016

Nanoscale zero-valent iron (nZVI) has been effectively applied for environmental remediation due to its ability to reduce various toxic compounds. However, quantification of nZVI reactivity has not yet been standardized. Here, we adapted colorimetric assays for determining reductive activity of nZVIs. A modified indophenol method was suggested to determine reducing activity of nZVI. The method was originally developed to determine aqueous ammonia concentration, but it was further modified to quantify phenol and aniline. The assay focused on analysis of reduction products rather than its mother compounds, which gave more accurate quantification of reductive activity. The suggested color assay showed superior selectivity toward reduction products, phenol or aniline, in the presence of mother compounds, 4-chlorophenol or nitrobenzene. Reaction conditions, such as reagent concentration and reaction time, were optimized to maximize sensitivity. Additionally, pretreatment step using $Na_2CO_3$ was suggested to eliminate the interference of residual iron ions. Monometallic nZVI and bimetallic Ni/Fe were investigated with the reaction. The substrates showed graduated reactivity, and thus, reduction potency and kinetics of different materials and reaction mechanism was distinguished. The colorimetric assay based on modified indophenol reaction can be promises to be a useful and simple tool in various nZVI related research topics.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.11-18
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• 2000

This study was conducted to establish an efficient screening method of membrane-disrupting herbicides, based on the result that membrane leakage leading to evolution of carbonyl compounds and aldehydes could be colorimetrically assessed by formation of stable chromophores with MBTH and ferric chloride. Assay conditions including plant material, light intensity, irradiation time, concentrations of reagents for colorization, and reaction time were optimized, and activities of different types of known herbicides were investigated with cucumber cotyledon discs. That result indicated that this assay was sensitive to membrane-disrupting herbicides, such as protoporphyrinogen oxidase inhibitors (acifluorfen, oxyfluorfen, oxadiazon) and an electron interceptor from photosystem I(paraquat). With seven compounds newly synthesized, highly positive correlation was observed between herbicidal activities measured by greenhouse bioassay and MBTH method. Because only a single disc(4 mm diameter) from cucumber cotyledon in 60 ${\mu}L$ of incubation solution was required to assay, a large number of herbicides could be tested simultaneously using 96-well microtitre plates. But the assay efficiency is not likely to significantly increase because of the boiling step during the reaction.

• The Korean Journal of Mycology
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• v.39 no.2
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• pp.99-104
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• 2011

Shiitake breeding requires the procedures of mating of two different parental strains and selection of hybrid strains that have good traits for the mushroom production. In this study, we tested the possibility of the use of chromogenic plate-based assay for extracellular enzyme production in order to assess and find good biochemical properties-possessed hybrid strains that were generated from genetic cross of the monokaryotic strains derived from two different parental strains of Lentinula edodes Sanjo-101ho and Sanjo-108ho. We observed that there was difference in the ability of producing ${\beta}$-glucosidase, avicelase, CM-cellulase, amylase, pectinase, xylanase, and protease among the monokaryotic strains. We could also comparatively assess that the ability of the seven extracellular enzymes production in the hybrid strains depended on the mating combination of the monokaryotic strains. Our results demonstrate that the assessment method for extracellular enzyme production using chromogenic plate assay could be usefully applied to the assessment of the hybrid strains derived from the breeding procedure of L. edodes.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.57-63
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• 2002

The hydropurification reaction of CTA (crude terephthalic acid) was carried out with hydrogen over PdRu/CCM (carbon-carbonaceous composite material) catalyst in a batch reactor at high temperature. The first order kinetics of hydropurification is confirmed with the linear dependence of ln(4-CBA; 4-carboxybenzaldehyde) with reaction time. The reaction condition studied is thought to represent the hydropurification well because of the linear dependence of catalytic activity on the catalyst weight. The p-toluic acid (p-tol) in solid and liquid increases with the conversion of reaction or the decrease of 4-CBA. However, the benzoic acid (BA) concentration does not depend much on the conversion. The AT (alkali transmittance) does not depend on the 4-CBA when the concentration is higher than about 0.2% which shows the 4-CBA, in itself, does not cause the coloring effect. The AT of PTA depends inversely with the concentration of 4-CBA when the 4-CBA is less than about 0.15%. This may show the coloring materials are removed in parallel with the hydrogenation of 4-CBA. The (0.3%Pd-0.2%Ru)/CCM shows larger residual catalytic activity than a commercial catalyst, 0.5%Pd/C, after using in a commercial reactor even though the former has smaller fresh activity than the latter. The palladium and ruthenium in PdRu/CCM show the synergetic effect in activity when the ruthenium concentration is about $0.2{\sim}0.35$ wt%. It may be supposed that the PdRu/CCM catalyst can be a promising candidate to replace the commercial Pd/C catalyst.

• Analytical Science and Technology
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• v.13 no.5
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• pp.549-557
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• 2000

FRIR-ATR spectrometry has been used to monitor the aqueous reactions of compounds without distinct chromophores in ultraviolet and visible regions. For example, hydrolysis reactions of ${\alpha}$-cyclodextrin and ${\gamma}$-cyclodextrin in acidic aqueous solution were studied. FTIR-ATR method has been used for the monitoring of cyclodextrin hydrolysis in 1.0 M. 0.5 M, and 0.1 M HCl solutions, respectively. We also found that the hydrolysis of ${\alpha}$-cyclodextrin produced glucose, but the hydrolysis of ${\gamma}$-cyclodextrin proceeded further to give more fragmented products than glucose.

• Journal of the Korean Chemical Society
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• v.27 no.3
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• pp.218-223
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• 1983

Triazinyl reactive dye containing two different chromophore was synthesized by using trifluoro-s-triazine as reactive component. The yield of this dye was 72% and its colour was yellowish red as a mixed shade. The hydrolysis rate and dyeing properties of this dye were studied and compared with monochlorotriazinyl reactive dye. It was found that monofluorotriazinyl reactive dye showed much higher hydrolysis rate than monochlorotriazinyl reactive dye.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.04a
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• pp.340-341
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• 2000

환경부에서 규제하고 있는 악취규제물질 중 자극적이며 화장실에서 나는 냄새와 유사한 성격을 가진 암모니아는 식품 및 화학공장 둥의 산업시설은 물론 환경기초시설, 대규모 농수산시장 등에서 발생하여 생활환경에서 빈번하게 감지할 수 있는 대표적인 악취유발물질의 하나이다. 이러한 암모니아를 분석할 수 있는 방법은 피리딘-피라졸론법, 네슬러법, 인도페놀법, CG-FTD법 둥 여러 실험방법이 제안되고 있으나 공기를 강제적으로 흡입하여 붕산흡수액과 접촉시켜 암모니아를 채취하고, 발색시약과의 반응에 의해 생성되는 푸른색의 인도페놀을 측정하여 암모니아를 정량하는 인도페놀법이 가장 광범위하게 이용되고 있다. (중략)

• Clean Technology
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• v.23 no.2
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• pp.196-204
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• 2017

CdZnS/ZnO composite was prepared through low-temperature precipitation and drying method. The property of CdZnS/ZnO as a recyclable photocatalyst for the degradation of rhodamine B (RhB) under visible light irradiation was examined. The sample was characterized by XRD, FE-SEM, XPS, UV-vis DRS and photoluminescence techniques before and after repeated reaction to investigate the change of properties during the photocatalytic reaction. During repeated reaction, the CdZnS/ZnO showed an improved photocatalytic activity and recycle stability. Among two feasible reaction pathways for photocatalytic degradation of RhB, the cleavage of conjugated chromophore was found to predominate over N-dealkylation of chromophore skeleton in the present work. The results indicate that the CdZnS/ZnO, prepared by a simple precipitation method, can be used as a visible-light driven photocatalyst with enhanced cycle stability and activity.

• Applied Microscopy
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• v.40 no.4
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• pp.261-266
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• 2010

ATP is the energy source synthesized at the electron transferase that consist of complex I, II, III, IV and V in mitochondrial cristae. The complex V functions as ATPase which composed of sub-complex $F_0$ and $F_1$. Porin or VDAC (voltagedependent anion-selective channel), is a family of small pore-forming proteins of the mitochondrial outer membrane, and play important roles in the regulated flux of anion, proton and metabolites between the cytosolic and mitochondrial compartments. The channel allows the diffusion of negatively charged solutes such as succinate, malate, and ATP in the fully open state, but of positively charged ions in subconducting state. In this study, in order to investigate the relationship of the function and localization between porin and ATPase we observed the distribution of porin and ATPase in the mitochondria of the bovine heart. Monoclonal antibodies against porin and ATPase ${\beta}$-subunit were used to detect porin and ATPase using light microscope with immunohistochemistry and immunofluorescence, and using electron microscope with immunogold-labeling. ATPase were stained in longitudinal section region in cardiac muscle, porin were stained in longitudinal section region in cardiac muscle. We viewed more specific pattern of localization and distribution of these proteins using immunofluorescence method. There were some region which were labeled with porin or ATPase respectively, and others which were labeled both proteins in cardiac muscle. The electron microscope results showed that immunogold labeled porin were labeled locally at mitochondrial outer membrane and ATPase were labeled evenly at mitochondrial cristae. But ATPase was not labeled at mitochondria cristae. These results confirmed the subcellular localizations of porin and ATPase in mitochondrial outer membrane and cristae. Also, we assumed that ATP synthesis always does not activation in all mitochondria exist in the bovine cardiac muscle.