• KSBB Journal
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• 제5권2호
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• pp.183-189
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• 1990

1,000l 규모의 인뇨로부터 순수한 urokinase를 정제하는 새로운 공정이 고안되었다. 2가 금속이온인 아연을 첨가하여 선택적으로 urokinase를 침전시켰으며, 이 방법은 뇨 중에 포함된 다른 단백질을 100~1,000배 농축할때도 사용할 수 있으며 10~20배의 경제효과를 얻었다. 침전물 속에 포함된 urokinate를 경제적으로 용출할기 위하여 0.1M EDTA/0.5M glycine, pH 9.0용액이 조성되었고, 용출액속에 포함된 높은 농도의 salt와 ion,뇨색소 등이 CM-Toyopeal column에 의해 신속하고 효과적으로 제거되었다. 최종적으로 사용된 benzamidine-Sepharose chromatog-raphy는 urokinase 정졔에 매우 효과적이었다. 이상의 공정을 통해, 1,000liter의 인뇨로부터 3$\times$$O^6IO$의 urokinase가 순수 정제 되었으며, 수욜은 약 50%, 정제도는 1,300배이었다. 또한 urokinase중에 12~14%의 pro-urokinase가 함유되어 있음이 확인되었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권2호
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• pp.122-127
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• 2005

A size exclusion chromatography (SEC) process, in the presence of denaturant in the refolding buffer was developed to refold recombinant human $interferon-\gamma$ ($rhIFN-\gamma$) at a high concentration. The $rhlFN-\gamma$ was overexpressed in E. coli resulting in the formation of inactive inclusion bodies (IBs). The IBs were first solubilized in 8 M urea as the denaturant, and then the refolding process performed by decreasing the urea concentration on the SEC column to suppress protein aggregation. The effects of the urea concentration, protein loading mode and column height during the refolding step were investigated. The combination of the buffer-exchange effect of SEC and a moderate urea concentration in the refolding buffer resulted in an efficient route for producing correctly folded $rhIFN-\gamma$, with protein recovery of $67.1\%$ and specific activity up to $1.2\times10^7\;IU/mg$.

• 대한방사성의약품학회지
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• 제3권2호
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• pp.98-102
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• 2017

We demonstrate a detail protocol for the radiosynthesis of a $^{125}I-labeled$ tetrazine prosthetic group and its application to the efficient radiolabeling of trans-cyclooctene-group conjugated human serum albumin (3) using inverse-electron-demand Diels-Alder reaction. Radioiodination of the stannylated precursor (2) was carried out by using [$^{125}I$]NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified $^{125}I-labeled$ azide ([$^{125}I$]1) was obtained with high radiochemical yield ($65{\pm}8%$, n = 5) and excellent radiochemical purity (>99%). Inverse-electron-demand Diels-Alder reaction between ([$^{125}I$]1) and 3 gave the $^{125}I-labeled$ human serum albumin ([$^{125}I$]4) with more than 99% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly indicate that the present radiolabeling method will be useful for the efficient and convenient radiolabeling of trans-cyclooctene-group containing biomolecules.

• Journal of Microbiology and Biotechnology
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• 제31권5호
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• pp.740-746
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• 2021

Efficient cellulolytic enzyme production is important for the development of lignocellulose-degrading enzyme mixtures. However, purification of cellulases from their native hosts is time- and labor-consuming. In this study, a constitutive expression system was developed in Penicillium oxalicum for the secreted production of proteins. Using a constitutive polyubiquitin gene promoter and cultivating with glucose as the sole carbon source, nine cellulolytic enzymes of different origins with relatively high purity were produced within 48 h. When supplemented to a commercial cellulase preparation, cellobiohydrolase I from P. funiculosum and cellobiohydrolase II from Talaromyces verruculosus showed remarkable enhancing effects on the hydrolysis of steam-exploded corn stover. Additionally, a synergistic effect was observed for these two cellobiohydrolases during the hydrolysis. Taken together, the constitutive expression system provides a convenient tool for the production of cellulolytic enzymes, which is expected to be useful in the development of highly efficient lignocellulose-degrading enzyme mixtures.

• KSBB Journal
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• 제23권6호
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• pp.557-560
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• 2008

본 연구에서는 식물세포배양으로부터 항암제 paclitaxel 정제를 위한 전처리 공정으로 계면활성제 (surfactant)를 이용한 마이셀(micelle) 공정을 개발하였으며, 특히 마이셀 공정에서의 계면활성제 영향에 대해 조사하였다. 마이셀은 친수성 그룹과 소수성 그룹으로 구성되어 있어 마이셀 내부로는 물에 녹지 않는 paclitaxel을 소수성 그룹이 감싸게 되고 외부는 친수성 그룹이 되어 수용액에 용해될 수 있게 된다. 따라서 식물세포인 biomass로부터 유기용매 추출액을 건조하여 상 분리에 적합한 유기용매에 녹인 후 마이셀 형성에 적합한 계면활성제를 첨가하고 교반하여 정체시키면 물에 녹지 않는 paclitaxel이 마이셀 내부의 소수성 그룹에 감싸여 수용액 상로 이동하고 paclitaxel을 제외한 여러 가지 불순물들 (특히 lipid 성분들)은 유기용매 상에 그대로 존재하게 되어 paclitaxel과 불순물들을 효율적으로 분리하게 된다. 본 실험에서는 분리 및 정제에 많이 쓰이는 대표적인 양이온(CPC, CTMAC, LTMAC), 음이온 (SDS, AOT), 비이온 (Tween, PEG, Triton) 계면활성제의 영향에 대한 실험을 수행하였다. 양이온 계면활성제인 CTMAC (5%, w/v)을 이용한 마이셀 공정에서 가장 높은 수율 (${\sim}99%$)과 순도 (${\sim}21%$)를 얻었으며 또한 마이셀 형성 후 상 분리에 30 min 정도 소요되어 가장 단시간에 상 분리가 이루어짐을 알 수 있었다. 전처리 공정에서의 마이셀 형성 및 상 분리 방법은 불순물로부터 효과적으로 높은 순도의 paclitaxel을 고수율로 회수할 수 있어 최종 정제를 위한 전처리 공정으로 매우 유용하게 활용될 수 있을 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제17권6호
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• pp.1-8
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• 2012

This study is to suggest a few efficient ways of rainwater utilization, through monitoring and analyzing 143 rainwater storage systems and 110 artificial recharge systems, which are installed in the recommended facilities by law, among the rainwater harvesting systems in Jeju Island. In the case that catchment facilities are damaged, rainwater could be contaminated by leaves and debris so that the rates of rainwater usages come to be lower. It is possible that contaminated rainwater could contaminate artificial recharge wells or rainwater discharging out of the rainwater harvesting system could result in flood and damage for the downgradient area. For maintaining high quality of rainwater and increasing rainwater utilization rate, it is necessary to install screening facilities and purification plant functioning precipitation and filtration. Also, in order to efficiently preclude the overflowing rainwater exceeding storage capacity, it is recommended to associate rainwater storage tanks with artificial recharge well or infiltration trench facilities.

• 화약ㆍ발파
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• 제27권2호
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• pp.56-60
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• 2009

물리학적 측면에서 에너지의 개념은 일하는 능력으로 정의된다. 기존의 석탄 석유등 화석연료를 대체하기 위해 1980년 이후부터 천연가스 원자력 등의 사용이 증가하였으나 환경오염문제로 태양열 풍력 조력 지열 등 대체에너지로의 전환을 촉진하고 있다. 그러나 에너지 이용효율 측면에서는 원자력 에너지와 화약 가스 등 화학에너지와는 비교가 되지 않는다. 본 논문에서는 환경(대체)에너지의 한계점을 뛰어 넘을 수 있는 방안을 연구하기 위하여 그린에너지의 현황을 조사하였으며, 고효율 에너지원에 대한 청정화와 응용 및 개발방향에 대해 검토, 연구 하였다.

• 한국세라믹학회지
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• 제52권3호
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• pp.173-179
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• 2015

We report the facile synthesis of graphene-$CdLa_2S_4$ composite through a facile solvothermal method at low temperature. The as-prepared products were characterized by X-ray diffraction (XRD) and by Scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis and BET analysis, revealing the uniform covering of the graphene nanosheet with $CdLa_2S_4$ nanocrystals. The as-prepared samples show a higher efficiency for the photocatalytic degradation of typical MB dye compared with P25 and $CdLa_2S_4$ bulk nanoparticles. The enhancement of visible-light-responsive photocatalytic properties by decolorization of Rh.B dye may be attributed to the following causes. Firstly, graphene nanosheet is capable of accepting, transporting and storing electrons, and thus retarding or hindering the recombination of the electrons with the holes remaining on the excited $CdLa_2S_4$ nanoparticles. Secondly, graphene nanosheet can increase the adsorption of pollutants. The final cause is that their extended light absorption range. This work not only offers a simple way to synthesize graphene-based composites via a one-step process at low temperature but also a path to obtain efficient functional materials for environmental purification and other applications.

• 대한방사성의약품학회지
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• 제4권2호
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• pp.85-89
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• 2018

We demonstrate a detail protocol for the radiosynthesis of an $^{125}I$-labeled MSTP prosthetic group and its application to the efficient radiolabeling of human serum albumin (HSA). Radioiodination of the precursor (2) was carried out by using $[^{125}I]$NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified $^{125}I$-labeled MSTP ($[^{125}I]1$) was obtained with high radiochemical yield ($73{\pm}5%$, n = 3) and excellent radiochemical purity (>99%). Site-specific reaction between ($[^{125}I]1$) and HSA gave the $^{125}I$-labeled human serum albumin ($[^{125}I]3$) with more than 99% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly demonstrate that the present radiolabeling method will be useful for the efficient and convenient radiolabeling of thiol-bearing biomolecules.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1697-1702
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• 2011

A facile, green, efficient and environment-friendly protocol for the synthesis of 14-aryl- or alkyl-14Hdibenzo[a,j]xanthene, 1,8-dioxooctahydroxanthene and 12-aryl-8,9,10,12-tetrahydrobenzo[a]xanthene-11-one have been developed by one-pot condensation of various aldehydes with (i) ${\beta}$-naphthol (ii) cyclic 1,3-dicarbonyl compounds and (iii) ${\beta}$-naphthol and cyclic 1,3-dicarbonyl compounds, in the presence of 1,3,5-trichloro-2,4,6-triazinetrion (trichloroisocyanuric acid, TCCA) as catalyst under solvent-free conditions. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, easy purification, and economic availability of the catalyst.