• The Korean Journal of Physiology
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• 제25권2호
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• pp.115-123
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• 1991

Molecular association of glucose transporters with the other proteins in the plasma membrane was assessed by gel electrophoresis and immunoblot techniques. Approximately $31.5{\pm}5.1%$ of GLUT-4, $64.8{\pm}2.7%$ of clathrin, 48.7% of total protein in the plasma membrane (PM) were found insoluble upon extraction with 1% Tx-100. Sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the Tx-100 insoluble PM fraction contained about 4 major polypeptides with apparent molecular weight of above 200, 100-120, 80 and 30-35 KDa that were readily removed upon wash with a high pH buffer which is known to remove clathrin and 0.5 M Tris-buffer which is known to remove assembly proteins (AP). Immunoblotting of GLUT4 and clathrin against specific antibodies showed that GLUT-4 and clathrin were co-solubilized up to 84.6% and 82.7% respectively by wash with a high pH buffer and 1% Tx-100. When the membrane was pre-washed with a high pH buffer and 0.5 M Tris solution, GLUT4 and clathrin were not solubilized further suggesting that GLUT4 molecules are in molecular association with clathrin, AP and/or other extrinsic membrane proteins in plasma membrane and the formation of clathrin-coated structures might be involved in insulin stimulated glucose transporter translocation mechanism.

• 한국응용과학기술학회지
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• 제19권4호
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• pp.265-272
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• 2002

$CaCO_{3}$ absorbed sodium lauryl sulfate (SLS) surfactant was prepared, Core-shell polymers of inorganic/organic pair, which have both core and shell component, were synthesized by sequential emulsion polymerization using styrene(St) as a shell monomer and potasium persulfate (KPS) as an initiator, We found that when $CaCO_{3}$; core prepared by adding 2,0 wt% SLS, $CaCO_{3}$ core/PSt shell polymerization was carried out on the surface of $CaCO_{3}$ particle without forming the new PSt particle during St shell polymerization in the inorganic/organic core-shell polymer preparation, The structure of core-shell polymer were investigated by measuring the degree of decomposition of $CaCO_{3}$ using HCl solution, thermal decomposition of polymer composite using thermogravimetric analyzer and morphology by scanning electron microscope.

• Macromolecular Research
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• 제17권12호
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• pp.1010-1014
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• 2009

Monodispersed microparticles with a poly(D,L-lactide-co-glycolide) (PLGA) core and a poly(ethyl 2-cyanoacrylate) (PE2CA) shell were prepared by Shirasu porous glass (SPG) membrane emulsification to reduce the initial burst release of doxorubicin (DOX). Solution mixtures with different weight ratios of PLGA polymer and E2CA monomer were permeated under pressure through an SPG membrane with $1.9\;{\mu}m$ pore size into a continuous water phase with sodium lauryl sulfate as a surfactant. Core-shell structured microparticles were formed by the mechanism of anionic interfacial polymerization of E2CA and precipitation of both polymers. The average diameter of the resulting microparticles with various PLGA:E2CA ratios ranged from 1.42 to $2.73\;{\mu}m$. The morphology and core-shell structure of the microparticles were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The DOX release profiles revealed that the microparticles with an equivalent PLGA:E2CA weight ratio of 1:1 exhibited the optimal condition to reduce the initial burst of DOX. The initial release rate of DOX was dependent on the PLGA:E2CA ratio, and was minimized at a 1:1 ratio.

• 한국미생물·생명공학회지
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• 제18권4호
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• pp.360-367
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• 1990

토양으로부터 rutin을 유일한 탄소원으로 생육하는 세균을 분리하여 그 중 rutin 가수분해활성이 높은 MT-57균을 Arthrobacter sp.로 동정하였다. Arthrobacter sp.MT-57에서 수 종류의 rutin 가수분해효소가 확인되었으며 이들 중 rutinosidase를 전기영동상 단일한 효소 단백질까지 정제하였다. Rutinosidase으 분자량은 SDS page와 gel filtration으로 부터 42,000의 단량체로 추정 되었다. 효소반응의 최적 pH와 온도는 pH 7.5와 $45^{\circ}C$였으며, 20분간 열처리하였을 때 $50^{\circ}C$까지 안정하였다.

• 상하수도학회지
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• 제18권6호
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• pp.724-730
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• 2004

Effects of the biosurfactant produced by Rhodococcus erythropolis on the solubilization and biodegradation of phenanthrene were investigated. Based on surface tension measurements, the average critical micelle concentration of the biosurfactant was estimated to be about 16mg TOC/L. The apparent solubility of phenanthrene increased linearly with the addition of biosurfactants above the CMC, and the concentration of solubilized phenanthrene was 38.9mg/L in 322mg TOC/L biosurfactant solution. The weight-solubilization ratio of biosurfactants for phenanthrene was approximately 118.8mg/g, this value was over 5 times greater than that of sodium dodecyl sulfate. Using a known phenanthrene degrader, batch phenanthrene biodegradation experiments were conducted with and without biosurfactants in liquid culture. The rate and extent of phenanthrene mineralization by the phenanthrene degrader with biosurfactants were much greater than those without biosurfactants. The greater phenanthrene mineralization observed in the presence of biosurfactants is attributed to the increased phenanthrene concentration in the aqueous culture due to the partitioning of the compound to biosurfactant micelles. The biosurfactant did not exhibit any toxic effect on mineralization of glucose by the phenanthrene-degrader.

• Animal cells and systems
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• 제16권6호
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• pp.455-461
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• 2012

Amongst the various antimicrobial peptides, lysozyme plays a central role in initiating and maintaining the antibacterial defense response of insect. Here we propose the biosynthesis and refolding of recombinant lysozyme in Escherichia coli expressed in inclusion body form. The Agrius lysozyme gene was amplified using gene specific primers and then ligated into the pGEX-4T-1 vector, which contained the glutathione S-transferase (GST) gene as a fusion partner. A recombinant lysozyme was expressed in E. coli Rosetta cells using a pGEX-4T-1 expression vector, and the fusion protein was induced by ioporpyl-${\beta}$-D-thiogalactopyranoside (IPTG). The recombinant protein produced as an inclusion body was resolubilized in solubilization buffer, and the resultant solution was dialyzed in refolding buffer. After thrombin cleavage, the recombinant lysozyme was purified by ion exchange chromatography and reverse phase chromatography. The recombinant lysozyme was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis and immunoreactivity against the anti-Agrius lysozyme was observed by western blot analysis of this protein. The recombinant lysozyme displayed antibacterial activity against Bacillus megaterium and Micrococcus luteus, which was confirmed by the inhibition zone assay.

• 한국응용과학기술학회지
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• 제28권2호
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• pp.140-145
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• 2011

Cationic gemini-surfactant, namely 1,4-butane-bis(N-alkanoyloxyethyl-N,Ndimethyl)-diammonium bromide was synthesized and their inhibition effect on corrosion of mild steel in 1 M HCl solution was tested by weight loss method. The synthesized product was confirmed by FT-IR and $^1H-NMR$ spectroscopy. Surface tensions were measured by surface tensiometer Sigma 70. Their c.m.c. values evaluated by surface tension method was $4.1{\times}10^{-5}{\sim}5.4{\times}10^{-5}$ mol/L. The Krafft point of the these surfactants were <0~$10.7^{\circ}C$. The emulsifying properties of synthesized cationic gemini surfactants and sodium dodecyl sulfate (SDS), tetradecyl trimethyl ammonium bromide (TTAB) was investigated. Of these, 1,4-butane-bis(N-lauroyloxyethyl-N,N-dimethyl)- diammonium bromide, CGL 14-4-14 has been confirmed as a good emulsifier. The inhibition efficiency increases by increasing cationic gemini surfactant concentration. As a result, these surfactants are expected to be applied as corrosion inhibitors.

• 한국응용과학기술학회지
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• 제31권1호
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• pp.1-6
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• 2014

Gemini type of cationic surfactant, namely ${\alpha},{\omega}$-alkane-bis(N-lauroyloxyethyl-N,N-dimethyl)-diammonium bromide was synthesized and confirmed by FT-IR and $^1H$-NMR spectroscopy. Their inhibition effect on corrosion of mild steel in 1 M HCl solution was tested by weight loss method. Surface tensions were measured by surface tensiometer Sigma 70. Their c.m.c. values evaluated by surface tension method was $4.01{\times}10^{-5}{\sim}4.99{\times}10^{-5}mol/L$. The Krafft point of the these surfactants were < $0^{\circ}C$. The emulsifying properties of synthesized cationic gemini surfactants and sodium dodecyl sulfate (SDS), tetradecyl trimethyl ammonium bromide (TTAB) was investigated. Of these, ${\alpha},{\omega}$-alkane-bis(N-lauroyloxyethyl-N,N-dimethyl)-diammonium bromide has been confirmed as a good emulsifier. The inhibition efficiency increases by increasing cationic gemini surfactant concentration. As a result, these surfactants are expected to be applied as corrosion inhibitors.

• 대한화학회지
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• 제32권3호
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• pp.195-202
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• 1988

Acetonitrile 용액중에서 3-phenyl-4-nitrosydnone의 전기화학전 환원을 direct current, differential pulse polarography, cyclic voltammetry 그리고 controlled potential coulometry 방법으로 연구하였다. Phenyl-N 단일 결합의 분리 이전에 nitro 기능기의 비가역적 전자 전달-화학반응(EC)기구의 진행으로 다전자 이동에 의한 amino(또한 hydroxylamino)기를 형성하고, 높은 음 전위 영역에서 2,3 비가역성 환원파의 일전자전달-화학반응에 의한 phenyl hydrazine을 생성하였다. 음극 반파 전위들은 cetyltrimethyl ammonium bromide의 억제 효과에 의해 음의 값으로 이동하였고 한편, sodium lauryl sulfate micelle은 높은 음전위 영역에서 제 2,3 환원파의 가역성산화 peaks를 보였다.

• Journal of Pharmaceutical Investigation
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• 제29권3호
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• pp.205-210
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• 1999

To formulate the parenteral delivery of a new cephalosporin derivative, 7-${\beta}$-[(2)-2-(2-arninothiazol-4-yl)-2methoxyiminoacetamido]- 3- [(2,3-cyclopenteno-4-carbamoyl-l-pyridinium)methyl]- 3-cephem-4-carboxylate sulfate( CKD604), the stability and solubility of CKD-604 in various aqueous media were investigated. The degradation kinetics of CKD-604 in aqueous solutions (ionic strength 0.1, pH 1-8) were studied at $37^{\circ}C$. The observed degradation rates followed pseudo first order kinetics. The pH-rate profile exhibited a minimum degradation rate at pH 5. The Arrhenius activation energy was 14.2 kcal/mol in pH 5 buffer solution. Excellent agreement between the cephalosporins' theoretical pH-rate profile and the experimental data indicated that the degradation pathway of CKD-604 could be predicted according to the general pathway of cephalosporins. The solubility of CKD-604 was 8.16 mg/ml at $25^{\circ}C$. To enhance the solubility and adjust the suitable pH, CKD-604 was solubilized by using sodium ascorbate, ascorbic acid and urea. The compositions were obtained to satisfy optimum pH and concentration, and the total amount of additives was several times of the active ingredient, CKD-604.