• Corrosion Science and Technology
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• 제16권4호
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• pp.161-166
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• 2017

The qualitative composition of active components of the corrosion inhibitor CGW-85567 was studied. It was found that С18:2 and С18:1 imidazolines and the corresponding imidazolin-amides are the major components. The HPLC/MS technique was developed for their determination in the water solutions of monoethylene glycol (MEG). Industrial application of the inhibitor showed that MEG solution retained high concentration of the inhibitor for a long time after ceasing its addition into pipelines. Low values of the partition coefficients (0.010-0.014) of imidazolines in the system "water solution of MEG (concentration of MEG 62-85% v/v) - gas condensate" have allowed to pass on from the technology of continuous pumping of the inhibitor into protected pipelines to the periodic dosing technology. Taking into account a long time of circulation in the system and high temperatures during MEG regeneration process possible degradation products of the inhibitor were studied. N, N-dimethyl-dodecanamine-1, and N, N-dimethyl-tetradecanamine-1 were identified as major degradation products of the corrosion inhibitor CGW-85567.

• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.895-900
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• 2002

A soil microorganism producing ${\alpha}$- and ${\beta}$-glucosidase inhibitors was identified as Bacillus lentimorbus, based on the fatty acid and morphological analyses, along with biochemical and physiological tests. The ${\alpha}$-glucosidase inhibitor was highly produced by this strain in a culture medium containing $0.25\%$ of sodium glutamate and $0.5\%$ of glucose, pH 8.0 at $30^{\circ}C$ for 2 days. The ${\alpha}$-glucosidase inhibitor from culture filtrate of his strain was identified as water soluble, organic solvent nonextractable, and heat stable. In addition to ${\alpha}$-glucosidase inhibitor, this strain also produced ${\beta}$-glucosidase inhibitor in he same culture medium and this inhibitor showed an antifugal activity against Botrytis cinerea. While the production of ${\alpha}$- glucosidase inhibitor was decreased by a glucose concentration higher than $1\%$, the production of ${\beta}$-glucosidase inhibitor was lot Influenced by a glucose concentration higher than $20\%$. The ${\alpha}$-glucosidase inhibitor from culture filtrate of this strain was separated from the ${\beta}$-glucosidase inhibitor through Sephadex G-100 column chromatography.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2002년도 창립10주년기념 및 국립독성연구원 의약품동등성평가부서 신설기념 국재학술대회:생물학적 동등성과 의약품 개발 전략을 위한 국제심포지움
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• pp.238-238
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• 2002

We studied whether kinase pathways are involved in TCDD-induced gene expression by treating specific kinase inhibitors ncluding MEK1 inhibitor PD98059, p38 inhibitor SB202190, PI-3 kinase inhibitor Wortmannin or LY294002 or protein tyrosine kinase inhibitor Genestein and then tested the effects of individual inhibitors on TCDD-induced gene expression of cytochromelAl gene (CYPlAl). Our results show that PD98059, MEK-1 inhibitor reduces dioxin-inducible transcription of CYPlAl. p44/p42MAPK, that is phosphorylated by Mek-1, are phosphorlylated by treatment of TCDD, peaking at lnM, 30min treatments. Overexpressions of p44/p42 MAPK dominant negative mutants suppress dioxin dependent transcription of DRE-driven reporter gene in a dose-dependent manner. Our results demonstrate that p44/p42 MAPK is essential for transcriptional activity of AHR/ARNT heterodimer. We found that PD98059 dose-dependently blocks TCDD-induced DRE binding of the AHR/ARNT heterodimer, thereby it reduces TCDD-induced gene expression. Therefore, our results indicate that Mek-1/p44/p42 MAPK pathway is involved in TCDD-induced gene expression, [This study was supported by a grant from Korean Research Foundation Grant (X01529)to H. Park]

• Tuberculosis and Respiratory Diseases
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• 제70권6호
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• pp.462-473
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• 2011

Background: Smoking is a risk factor for idiopathic pulmonary fibrosis (IPF), but the mechanism of the association remains obscure. There is evidence demonstrating that plasminogen activator inhibitor-1 (PAI-1) is involved in the progression of pulmonary fibrosis. This study was to determine whether the administration of small interfering RNA (siRNA) targeting PAI-1 or PAI-1 inhibitor to the cigarette smoking extract (CSE)-exposed rat alveolar type II epithelial cells (ATII cells) limits the epithelial-mesenchymal transition (EMT). Methods: ATII cells were isolated from lung of SD-rat using percoll gradient method and cultured with 5% CSE. The EMT was determined from the ATII cells by measuring the real-time RT PCR and western blotting after the PAI-1 siRNA transfection to the cells and after administration of tiplaxtinin, an inhibitor of PAI-1. The effect of PAI-1 inhibitor was also evaluated in the bleomycin-induced rats. Results: PAI-1 was overexpressed in the smoking exposed ATII cells and was directly associated with EMT. The EMT from the ATII cells was suppressed by PAI-1 siRNA transfection or administration of tiplaxtinin. Signaling pathways for EMT by smoking extract were through the phosphorylation of SMAD2 and ERK1/2, and finally Snail expression. Tiplaxtinin also suppressed the pulmonary fibrosis and PAI-1 expression in the bleomycin-induced rats. Conclusion: Our data shows that CSE induces rat ATII cells to undergo EMT by PAI-1 via SMAD2-ERK1/2-Snail activation. This suppression of EMT by PAI-1 siRNA transfection or PAI-1 inhibitor in primary type II alveolar epithelial cells might be involved in the attenuation of bleomycin-induced pulmonary fibrosis in rats.

• 상하수도학회지
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• 제19권1호
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• pp.68-77
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• 2005

This study was performed to evaluate the application of corrosion inhibitor and to examine the correlation between corrosion rate and red water in a series of batch tests and a test using auto corrosion monitoring system at A water treatment plant in Gyeonggido. The corrosion study in the auto corrosion monitoring system indicated that Fe concentration decreased by 30~50% and corrosion rate also reduced remarkably with corrosion inhibitor at $1.8mg\;PO_4/L$. After addition of corrosion inhibitor, it was indicated the effective adsorption of the inhibitor on the surface of the pipe line forming a protective film. The corrosion rate increases with the increase in Fe concentration. With $1.8mg\;PO_4/L$ of corrosion inhibitor, the corrosion rate decreased remarkably. Fe concentration had correlation to not only red water problems but also the corrosion rate that actually dissolved into the water, primarily due to the deposition of oxidized iron or other compounds as a scale, which serves as a large reservoir of corrosion by-product. Therefore, corrosion rate can be estimated by Fe concentration. For these reasons, an effective corrosion inhibitor is also an effective red water control reagent. The effect of the corrosion inhibition can last for some time even the application the corrosion inhibitor is discontinued. For the cost effective and efficient corrosion control, the concentration and timing of corrosion inhibitor addition must be determined properly.

• Korean Journal of Mathematics
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• 제9권1호
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• pp.9-20
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• 2001

We are concerned with an activator-inhibitor system proposed by Ohta [8]. The purpose of this paper is to study the dynamics of interfaces in an interfacial problem which is reduced from the system in order to examine how this problem is different from an activator-inhibitor system [3, 7].

• Asian-Australasian Journal of Animal Sciences
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• 제4권3호
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• pp.285-291
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• 1991

Two experiments were conducted to evaluate the effect of mold inhibitor in the ration which had two different protein levels (18% and 12%) and two different particle sizes (80 or 40% of the particles in the ration less than 1.19 mm). The experimental diets with ave. 12.7% moisture which were treated at the level of 0.1% mold inhibitor were stored under 85% humidity and at $29{\pm}1^{\circ}C$ for 10 to 40 days. In experiment 1, after 40 days of storage the $CO_2$ production in the feed treated with mold inhibitor was higher (p < 0.01) than when 40% of the ration's panicle size was 1.19 mm. Aflatoxin production in the experimental diet with mold inhibitor was affected (p<0.05) by the levels of protein and the different particle size ranges after 40 days storage. The interaction of protein levels and particle size ranges on the anatoxin and $CO_2$ production was significant (p<0.05) at 40 days storage. In experiment 2, there was a decrease in total body weight gain and total feed intake observed in chicks fed the untreated diet of 18% protein with 40% of the particles in the ration less than 1.19 mm stored for 40 days. Feed conversion was depressed (p<0.05) in the chicks fed the untreated diets of both particle sizes. Particle size X types of feed interaction in feed conversion was significant (p<0.05).

• Mycobiology
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• 제41권3호
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• pp.149-154
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• 2013

An ${\alpha}$-glucosidase inhibitor was developed from Aspergillus oryzae N159-1, which was screened from traditional fermented Korean foods. The intracellular concentration of the inhibitor reached its highest level when the fungus was cultured in tryptic soy broth medium at $27^{\circ}C$ for five days. The inhibitor was purified using a series of purification steps involving ultrafiltration, Sephadex G-25 gel permeation chromatography, strong cation exchange solid phase extraction, reverse-phase high performance liquid chromatography, and size exclusion chromatography. The final yield of the purification was 1.9%. Results of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis indicated that the purified ${\alpha}$-glucosidase inhibitor was a tri-peptide, Pro-Phe-Pro, with the molecular weight of 360.1 Da. The IC50 value of the peptide against ${\alpha}$-glucosidase activity was 3.1 mg/mL. Using Lineweaver-Burk plot analysis, the inhibition pattern indicated that the inhibitor acts as a mixed type inhibitor.

• 약학회지
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• 제37권2호
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• pp.149-157
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• 1993

Protein methylase inhibitor which is a modulator of biological methylation has been purified and characterized from porcine liver soluble fraction by cell fractionation, Sephadex G25 chromatography, reverse phase HPLC, size exclusion HPLC. The results are summarized as follows. 1) The purified inhibitor shows apparent homogeneity, as judged by HPLC. 2) A molecular weight of the purified inhibitor which is composed of 18 amino acid residues is about 1,400 daltons. 3) A single absorption peak of ultraviolet spectrum was observed at 260nm. 4) The inhibitor was not inactivated by heating at $100^{\circ}C$ until 60min. and its activity was not influenced by treatment with digestive enzymes, such as trypsin, pepsin, pronase, chymotrypin, lysozyme, DNase, and RNase. 5) The purified inhibitor inhibited protein rnethylase I, II, III and phospholipid methyltransferase activities. 6) The purified inhibitor inhibited noncompetitively protein methylase II from porcine liver, spleen, and testis. 7) The $K_{i}$ values for protein methylase II from porcine liver, spleen, and testis were 300nM, 250nM, 297nM, respectively.

• 한국미생물·생명공학회지
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• 제23권5호
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• pp.602-608
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• 1995

The aim of the present research program was to construct an optimum fermentation system and to characterize the properties of cathepsin B inhibitor from Streptomyces chromofuscus SMF28. Glucose and casitone were proved to be good carbon source and nitrogen source, respectively. The production of inhibitor was high at lower concentration than 10 mM of inorganic phosphate. The optimum temperature and pH for the production of inhibitor were 30$\circ$C and pH 7, respectively. The production of inhibitor was related to mycelial growth and was affected by medium composition. The inhibitor in culture filtrate of S. chromofuscus SMF28 was purified by butanol extraction, silica gel chromatography, Amberlite IRC-50 (H$^{+}$ form) chromatography, preparative TLC, and preparative HPLC. From amino acid analysis and UV, IR, $^{1}$H-NMR spectroscopic analysis, the inhibitor was identified as a peptide containing valine and phenylalanine derivative.