• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1848-1850
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• 2014

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1548-1551
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• 2004

studied on the physicochemistrical property of the clean active water depositting on the ceramic stone by the mineral-Oriental medicine. The results are as follows. The cluster of the clean active water is observed 53-66.5㎐ for contral water. The clean active water is observed 7.2 ph and 1.3330 refractive index for contral water. In the chemical experimental test by ICP, the clean active water is observed 102℃ in boiling point and 4.8㎎/100g V.E for 0㎎g/100g of contral water. In the antibiotic experimentation, an anion, the dimintion index of bacilli, radiation degree and radiate energy of the clean active water increased for contral water. And in the deodorization experimentation, the clean active water is observed 95% deodorization index.

• CELLMED
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• v.2 no.2
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• pp.20.1-20.5
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• 2012

$Gynura$ $segetum$ (Lour.) Merr. ($Compositae$) is a well recognized medicinal plant in Indonesia and Malaysia. It is believed to have an anticoagulant effect and is used in treating snake-bites, inflammations and other skin afflictions. This study was carried out to evaluate the antimicrobial effects of $Gynura$ $segetum$ leaves extracts and its fractions. The chemical compositions of the active extracts were also determined. The antimicrobial activities of different solvent extracts of leaves of $Gynura$ $segetum$ were evaluated using the agar well-diffusion method. The Minimum Inhibitory Concentration (MIC) of the active subfractions was determined by the tube dilution method. Gas Chromatography-mass spectrometry (GC-MS) analysis was carried out to identify the chemical compositions of the active extracts. The ethyl acetate fraction and its subfraction E4 performed potent antimicrobial activities and fifteen known chemical constituents were identified by GCMS analysis as 4-vinylphenol, 1-tetradecene, phenol, 2,4-bis(1,1-dimethylethyl), 1-hexadecene, E-15-heptadecenal, hexadecanoic acid, 1,2-benzenedicarboxylic acid, dibutyl ester, 1-docosene, octadecanoic acid, 1-eicosene, cyclotetracosane, 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl)ester, butanedioic acid, monomethyl ester, niacin and 4-hydroxy-benzoic acid. The results of this study suggested a connection between the antimicrobial activities and the chemical structures. The plant may be used as a potential source for antimicrobial agents.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.280-284
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• 2016

In this study, the extractable content of each parameters from angelica was confirmed using conventional solvent extraction and microwave extraction in order to extract the functional active ingredient. In addition, the functionality of active ingredients was evaluated by measuring the antioxidant activity and the flavonoids and total polyphenols of the active ingredient extracted from angelica, For the conventional solvent extraction at optimal conditions of the extraction time (2 h), ethanol/pure water volume ratio (60%), the extraction temperature ($60^{\circ}C$), 20.6 wt% of the active ingredient were extracted. Also, when using microwave extraction at optimal conditions of the microwave irradiation time (6 min), microwave intensity (600 W) and ethanol/pure water volume ratio (60 vol%) 22.8 wt% of the active ingredient were extracted. The microwave method required shorter time to complete extraction compared to that of using the conventional solvent extraction method. The antioxidant activity of active ingredients extracted from angelica was 31.46% of DPPH radical scavening activity. The flavonoid content was 14.20 mg QE/mg dw, and total polyphenol content was 11.70 mg GAE/g when using the microwave extraction process.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.405-412
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• 2019

In this study, the physical and chemical properties of mortar are evaluated by micro-analysis, taking into account the substitution rate(20%, 30%, and 40%) of zeolite with porous properties and active hwangtoh. First, the physical and chemical properties of zeolite and active hwangtoh are reviewed to confirm that the specific surface area of those is similar with ordinary portland cement, and the main chemical composition is SiO₂, Al₂O₃, Fe₂O₃, etc.. So, it is thought that they have the properties of pozolan reactive materials. As the results of the strength test considering the amount of substitution based on that of cement, It is confirmed that strength decreases with the increase of the replacement amount of zeolite and active hwangtoh, and the strength of mortar with replacement rate of 20% is higher than OPC mortar. It is confirmed that the amount of porosity is increased due to chemical properties of zeolite and active hwangtoh, and in particular, the size of the pore is greater than 1㎛ in mortar mixed with active hwangtoh.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.173-177
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• 1997

Glycerol-3-phosphate cytidylyltransferase from Bacillus subtilis was modified with various chemical modifiers to determine the active sites of the enzyme. Treatment of the enzyme with group-specific reagents diethylpyrocarbonate, N-bromosuccinimide, or carbodiimide resulted in complete loss of enzyme activity, which shows histidine, tryptophan, and glutamic acid or aspartic acid residues are at or near the active site. In each case, inactivation followed pseudo first-order kinetics. Inclusion of glycerol-3-phosphate and/or CTP prevented the inactivation, indicating the presence of tryptophan and glutamic acid or aspartic acid residues at the substrate binding site. Analysis of kinetics of inactivation showed that the loss of enzyme activity was due to modification of a two histidine residues, single tryptophan residue, and two glutamic acid or aspartic acid residues.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.173-176
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• 2008

MJ0684 from Methanococcus jannaschii is a hypothetical protein belonging to the subfamily Ig of amino acid aminotransferases. In the present study, the crystal structure of MJ0684 has been determined at 2.2 resolution. It reveals that MJ0684 has an overall structure similar to subfamily Ig aminotransferases and its active site architecture is most similar to that of kynurenine aminotransferases among several kinds of aminotransferases in the subfamily Ig?. It has two hydrophobic active site residues conserved in the kynurenine aminotransferases for recognizing hydrophobic substrates. In addition, the absence of any basic residue for recognizing the side chain carboxylic group of the aspartate in the active site rules out the possibility that MJ0684 would act as an aspartate aminotransferase. These structural observations collectively imply that MJ0684 is a novel archaeal homolog of the subfamily Ig kynurenine aminotransferase.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.711-714
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• 2004

Peroxynitrite enters erythrocytes through band 3 anion exchanger and oxidizes cytosolic proteins therein. As a protein associated with band 3, carbonic anhydrase II may suffer from peroxynitrite-induced oxidative damages. Esterase activity of carbonic anhydrase II decreased as the concentration of peroxynitrite increased. Neither hydrogen peroxide nor hypochlorite affected the enzyme activity. Inactivation of the enzyme was in parallel with the release of zinc ion, which is a component of the enzyme's active site. SDS-PAGE of peroxynitrite-treated samples showed no indication of fragmentation but non-denaturing PAGE exhibited new bands with lower positive charges. Western analysis demonstrated that nitration of tyrosine residues increased with the peroxynitrite concentration but the sites of nitration could not be determined. Instead MALDI-TOF analysis identified tryptophan-245 as a site of nitration. Such modification of tryptophan residues is responsible for the decrease in tryptophan fluorescence. These results demonstrate that peroxynitrite nitrates tyrosine and tryptophan residues of carbonic anhydrase II without causing fragmentation or dimerization. The peroxynitrite-induced inactivation of the enzyme is primarily due to the release of zinc ion in the enzyme's active site.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2419-2421
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• 2009

A simple and efficient method has been developed for Knoevenagel condensation between aldehydes or ketones and active methylene group by stirring in methylene chloride at 60 ${^{\circ}C}$ under heterogeneous conditions using silica supported ammonium acetate. The products are obtained in excellent yields and are in a state of high purity. The structures of the products were confirmed by IR, $^1H$ NMR and mass spectral data and comparison with authentic samples available commercially.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.30-34
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• 2014

We report a novel approach for fabricating active surface-enhanced Raman scattering (SERS) substrate for sensitive detection. This approach is based on the assembling of gold nanoparticles (AuNPs) onto the electrospun polycaprolactone (PCL) nanofiber film. The hydrophobic surface of PCL nanofiber film was pretreated using UV-inducing graft polymerization with acrylic acid. Afterwards this PCL nanofiber film was incubated with the AuNP solution to promote the assembly of AuNPs onto the PCL nanofibers and the formation of SERS active substrate. 4-aminothiophenol (4-ATP) molecule was used as a test probe for SERS experiments, indicating that the substrate has high sensitivity to SERS response. Our method has great advantage in term of environment-friendly synthesis, large-scale, high stability and good reproducibility. This highly active SERS substrate can be employed to detect the drug molecule, 2-thiouracil.