• Title/Summary/Keyword: polyethylene glycol(PEG)

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Effects of Polyethylene Glycol on Glucoamylase Production in Recombinant Yeast Culture (Polyethylene Glycol이 재조합 효모 배양에 의한 Glucoamylase 생산에 미치는 영향)

  • 차형준;유영제
    • KSBB Journal
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    • v.11 no.3
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    • pp.311-316
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    • 1996
  • The effects of polyethylene glycol (PEG) on glucoamylase production in recombinant Saccharomyces cerevisiae were studied. By PEG addition, the cell growth was not affected. However, the glucoamylase production was increased in all range of PEG molecular weights and concentrations. The optimal molecular weight of PEG was 6000 and the optimal concentration was 1g/L. Using these optimals, the extracellular glucoamylase activity was 23% higher in PEG-containing medium than that in medium without PEG.

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Enhancement of Dissolution from Pharmaceutical Preparation of Hydrophobic Drugs ( II ) -Dissolution Rates of Sulpiride-Polyethylene Glycol Coprecipitates- (Sulpiride-Polyethylene Glycol Coprecipitates의 용출속도(溶出速度)에 관한 연구(硏究))

  • Ku, Young-Soon
    • Journal of Pharmaceutical Investigation
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    • v.13 no.3
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    • pp.100-103
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    • 1983
  • Coprecipitates of sulpiride and polyethylene glycol (PEG) decrease the dissolution rate of sulpiride and the degree of decrease is reversely proportional to molecular size of PEG and proportional to increase of PEG ratios in coprecipitates. The physical mixtures of sulpiride and PEG increase the dissolution rate of sulpiride.

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Oxidative Conversion of Bisphenol A with Laccase in the Presence of Polyethylene Glycol (Polyethylene glycol (PEG) 수용액에서 laccase를 이용한 비스페놀A의 처리)

  • Kim, Young-Jin
    • Journal of Environmental Health Sciences
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    • v.31 no.4 s.85
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    • pp.241-245
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    • 2005
  • Laccase catalyzes the oxidation and polymerization of aromatic compounds in the presence of molecular oxygen. Studies were conducted to characterize the use of polyethylene glycol (PEG) as an additive to keep up the enzymatic stability. The enzymatic activities highly remained and bisphenol A (BPA) was rapidly converted in the presence of 5 mg/l of PEC. These effects were accomplished with PEG of molecular weight 3,350. A linear relationship was found between the quantity of BPA to be converted $(10-120\;{\mu}M)$ and the optimum dose of PEC required for greater than $95\%$ conversion. This result suggests that it is the interaction between the PEG and the reaction products. In the optimum dose of PEG, the aeration of reaction mixture neither enhanced the conversion of BPA nor retarded the inactivation of the enzyme.

Effects of the Methods of Polyethylene Glycol Impregnation and Drying on the Volumetric Shrinkage of Wood (Polyethylene Glycol 주입방법과 건조방법이 목재 부피수축률에 미치는 효과)

  • Lee, Won-Hee;Kang, Chun-Won;Hong, Seung-Hyun;Kang, Ho-Yang
    • Journal of the Korea Furniture Society
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    • v.27 no.1
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    • pp.43-48
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    • 2016
  • PEG (Polyethylene glycol) impregnation in wood reduces the occurrence of checking during kiln drying. The volumetric shrinkages of wood PEG impregnated by pressure (PEG-P) or soaking (PEG-S) methods, and oven-dried by vent (VD) or air-tight (AD) methods were measured and compared with the controls. The average oven-dry weight of PEG impregnated specimens was larger than that of the controls by 3.6 g, but was not influenced by the drying methods. The average of the total volumetric shrinkage of PEG-P-VD specimens was the least (2.3%), while that of CON-S-AD specimens was the largest (28.9%). Within a drying method the total volumetric shrinkage of the control was the largest followed by PEG-S and PEG-P specimens, which implied that residual PEG in wood restrained its shrinkage during drying.

Mechanical properties of domestic small-diameter logs treated with Polyethylene glycol (PEG(Polyethylene Glycol)처리재의 역학적 특성)

  • 권구중;김남훈
    • Journal of the Korea Furniture Society
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    • v.12 no.2
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    • pp.19-27
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    • 2001
  • This study was carried out to investigate the mechanical properties of woods treated with 30% aqueous solution of PEG 1000. Compressive, bending and shearing strengths were slightly decreased by PEG treatment. Absorbed energy in impact bending did not show any significant differences between untreated and PEG-treated woods.

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Polyethylene glycol (PEG)-modified cationic liposome mediated gene delivery

  • Kim, Jin-Ki;Choi, Sung-Hee;Ahn, Woong-Shick;Kim, Chong-Kook
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.426.1-426.1
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    • 2002
  • In this study. we modified the cationic liposomes by polyethylene glycol (PEG)-grafted or PEG-added methods. The PEG-grafted transfection complexes were prepared by adding the plasmid DNA to the PEG-grafted cationic liposomes, composed of PEG and cationic lipids. PEG-added transfection complexes were prepared by adding the PEG to the mixture of cationic lipids and plasmid DNA. The particle sizes of PEG-modified transfection complexes did not change during storage compared to conventional transfection complexes. (omitted)

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The Effect of Polyethylene Glycol on the Trivalent Chromium Electroplating (Polyethylene glycol이 3가크롬 전기도금에 미치는 효과)

  • Lee, Joo-Yul;Phuong, Nguyen Van;Lim, Sung-Hwan;Han, Seung-Zeon;Kwon, Sik-Chol
    • Journal of Surface Science and Engineering
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    • v.44 no.1
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    • pp.7-12
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    • 2011
  • The effect of organic additives, polyethylene glycol (PEG), on the trivalent chromium electroplating was analysed in the view point of current efficiency, solution stability and metallurgical structure. It was measured that PEG-containing trivalent chromium solution had about 10% higher current efficiency than pure solution and controlled the micro-crack density of electrodeposits. PEG exhibited profound effect on the solution stability by reducing the consumption rate of formic acid which acts as a complexant to lower the activation energy required for electrochemical reduction of trivalent chromium ions. It was also revealed that the formation of chromium carbide layer was facilitated in the presence of polyethylene glycol, which meant easier electrochemical codeposition of chromium and carbon, not single chromium deposition. Trivalent chromium layer formed from PEG-containing solution was amorphous with local nano-crystalline particles, which were prominently developed on the entire surface after non-oxidative heat treatment.

Enhancing Transfection Efficiency Using Polyethylene Glycol Grafted Polyethylenimine and Fusogenic Peptide

  • Lee, Haeshin;Jeong, Ji-Hoon;Lee, Je-Hoon;Park, Tae-Gwan
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.6 no.4
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    • pp.269-273
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    • 2001
  • This study presents a new formulation method for improving DNA transfection effi-ciency using a fusogenic peptide and polyethylene glycol-grafted polyethylenimine. Succinimidyls succinate polyethylene glycol (PEG-SSA) was conjugated with polyethylenimine(PEL). PEL is well known for a good endosomal escaping and DNA condensign agent. The positively charged syn-thetic fusogenic peptide, KALA was coated on the negatively charged PEG-g-PEI/DNA and PEI/DNA complexes. The KALA/PEI/ DNA complexes exhibited aggregation behavior at higher KALA coating amount with an effective diameter of around 1,000 nm. However, the LALA/PEG-g-PEI/DNA complexes were 100-300 nm in size with a surface zeta-potential (ζ)value of about +20mV. The conjugated PEG molecules suppressed any KALA-mediated inter-particle aggregation, and thereby improved the transfection efficiency, Consequently, the transfection efficiency of the KALA/PEG-g-PEI/DNA complexes was obtained by utilizing both the fusogenic activity of KALA and the steric repulsion effect of PEC.

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Chemical Modification of Sheep Hemoglobin with Methoxy-Polyethylene Glycol

  • Jeong, Seong-Tae;Byun, Si-Myung
    • BMB Reports
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    • v.29 no.3
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    • pp.261-265
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    • 1996
  • Sheep hemoglobin (SHb) was modified with methoxy-polyethylene glycol (mPEG) to develop a potential blood substitute. mPEG has been used to decrease antigenicity and immunogenicity of foreign proteins. When the mPEG was attached to SHb, the modified hemoglobins showed decreased electrophoretic mobility on SDS-PAGE and decreased free amino groups. When the remaining free amino groups of mPEG modified SHb were determined by TNBS free amino group titration methods. about 34% of total free amino groups were modified with mPEG. This mPEG-SHb conjugate of 34% amino groups modified showed no precipitation by double immunodiffusion with polyclonal antibodies against SHb. This modified hemoglobin still has oxygen transport activity. So this antigenicity decreased hemoglobin may be used in humans as a potential blood substitute.

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Syntheses of Biologically Non-Toxic ZnS:Mn Nanocrystals by Surface Capping with O-(2-aminoethyl)polyethylene Glycol and O-(2-carboxyethyl)polyethylene Glycol Molecules

  • Kong, Hoon-Young;Song, Byung-Kwan;Byun, Jonghoe;Hwang, Cheong-Soo
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1181-1187
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    • 2013
  • Water-dispersible ZnS:Mn nanocrystals were synthesized by capping the surface of the nanocrystal with O-(2-Aminoethyl)polyethylene glycol (PEG-$NH_2$, Mw = 10,000 g/mol) and O-(2-Carboxyethyl)polyethylene glycol (PEG-COOH, Mw = 10,000 g/mol) molecules. The modified PEG capped ZnS:Mn nanocrystal powders were thoroughly characterized by XRD, HR-TEM, EDXS, ICP-AES and FT-IR spectroscopy. The optical properties were also measured by UV/Vis and photoluminescence (PL) spectroscopies. The PL spectra showed broad emission peaks at 600 nm with similar PL efficiencies of 7.68% (ZnS:Mn-PEG-NH2) and 9.18% (ZnS:Mn-PEG-COOH) respectively. The measured average particle sizes for the modified PEG capped ZnS:Mn nanocrystals by HR-TEM images were 5.6 nm (ZnS:Mn-PEG-NH2) and 6.4 nm (ZnS:Mn-PEG-COOH), which were also supported by Debye-Scherrer calculations. In addition, biological toxicity effects of the nanocrystals over the growth of wild type E. coli were investigated. They showed no biological toxicity to E. coli until very high concentration dosage of 1 mg/mL of the both nanocrystal samples.