• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.103-106
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• 2002

Solubilization isotherms for methyl tort-butyl ether (MTBE) in sodium dodecyl sulfate(SDS), dowfax 8390, sodium dodecylbenzenesulfonate and cetylpyridinium chloride (CPC) were investigated for application to micellar enhanced remediation. Dowfax 8390 showed maximum extent of solubilization among surfactants tested in this study. It seems that sulfate group in anionic surfactants playes a important role in solublization of MTBE. Chemical shiftes in NMR of surfactant and MTBE supports this point.

• Journal of Pharmaceutical Investigation
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• 제40권spc호
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• pp.45-61
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• 2010

Polymeric based nanomedicines have been developed for diagnosing, treating, and preventing diseases in human body. The nanosized drug delivery systems having various structures such as micelles, nanogels, drug-conjugates, and polyplex were investigated for a great goal in pharmaceutics: increasing therapeutic efficacy for diseases and decreasing drug toxicity for normal tissues. The functional polymers used for constituting these drug delivery systems should have several favorable properties such as stimuli-responsibility and biodegrdability for controlled drug release, and solublization capacity for programmed drug encapsulation. This review discusses recent developments and trends of functional polymers (e.g., pH-sensitive polymers, biodegradable polymers, and cationic polymers) used for nanosized drug carriers.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.311-315
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• 1995

Assay conditions for screening of $\beta$-1,3-glucan synthase inhibitor were evaluated. Cells in the beginning of mid-log phase showed the highest activity of the $\beta$-1,3-glucan synthase. Cells permeabilized with 1% digitonin treatment could be used as a good crude enzyme source for convenient screening of the $\beta$-1,3-glucan synthase inhibitors. Calcofluor white (0.125% in final) and papulacandin B (25 $\mu$g/ml) inhibit 90% and more than 50% of the $\beta$-1,3-glucan synthase activity, respectively. Cells grown at 37$\circ$C showed higher enzyme activity than those of 25$\circ$C. Catalytic factor of the $\beta$-1,3-glucan synthase was solubilized from particulated membrane preparations, holoenzyme, by extracting with 0.00938% CHAPS.

• BMB Reports
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• 제41권5호
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• pp.404-407
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• 2008

A 345-bp gene that encodes human bone morphogenetic protein-2 (hBMP-2) has been synthesized. The codon usage of the resulting gene was modified to include those triplets that are utilized in highly expressed Escherichia coli genes. The hBMP-2 gene was efficiently expressed in E. coli as a soluble and active protein. Since the recombinant hBMP-2 was readily solublized, no further solublization steps were required throughout purification. No additional tagging residues were introduced into the synthetic hBMP-2 gene product. The developed synthetic gene is a promising approach for scaling-up the soluble expression of hBMP-2.

• 한국토양비료학회지
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• 제47권2호
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• pp.127-132
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• 2014

The effect of thermal pretreatment conditions on hydrolysis characteristics of dairy manure and sawdust mixtures has been evaluated. Thermal pretreatment temperature varied between 35 and $120^{\circ}C$ and the period of the treatment changed between 30 and 1440min (24h). As thermal pretreatment temperature and duration increased, organic material solublization rates were improved. Maximum solubilizations of chemical oxygen demand (SCOD), carbohydrates, and volatile fatty acids(VFAs) were observed when dairy manure treated for one day at $120^{\circ}C$. Although one day treatment duration at $120^{\circ}C$ showed the highest SCOD, soluble carbohydrates, and VFAs concentration, its hydrolysis rate was only about 12%. The results reveal that the thermal pretreatment conditions tried in this study are not enough to solubilize the organic matter contained in dairy manure and sawdust mixtures. In order to maximize hydrolysis performance, the further research needs to determine the factors influences on organic material solubilization in addition to thermal pretreatment temperature and duration.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.586-589
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• 2001

본 연구에서는 P. agglomerans를 이용하여 불용성 인산염인 hydroxyapatite 와 인광석을 가용화 하여 유리 인산을 생산하였고, P. agglomerans를 Ca-alginate에 고정화하여 이를 불용성 인산염을 가용화시키는 가능성올 조사하였다. HY 배지에 서 $30^{\circ}C$, lOOrpm 으로 pH 7에서 48시간 배양한 경우 520mg/L 의 유리인산이 생성되었고 hydroxyapatite 대신 같은 농도의 인광석을 첨가하였을때 생성되는 유리 인산 의 양은 86.09mg/L였다. 또한 P. agglomerans를 Ca-alginate에 고정화하였을 때 HY 배지에서 같은 조건으로 120 시간 동안 계속적으로 인산이 생성되었고 , 이때 생성된 인산의 농도는 74Omg/L였으며, 인광석을 첨가한 경우에서도 182mg/L 정도의 유리 인산이 생성되었다.

• 한국토양비료학회지
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• 제44권4호
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• pp.625-636
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• 2011

Cold-adapted bacteria survive in extremely cold temperature conditions and exhibit various mechanisms of adaptation to sustain their regular metabolic functions. These adaptations include several physiological and metabolic changes that assist growth in a myriad of ways. Successfully sensing of the drop in temperature in these bacteria is followed by responses which include changes in the outer cell membrane to changes in the central nucleoid of the cell. Their survival is facilitated through many ways such as synthesis of cryoprotectants, cold acclimation proteins, cold shock proteins, RNA degradosomes, Antifreeze proteins and ice nucleators. Agricultural productivity in cereals and legumes under low temperature is influenced by several cold adopted bacteria including Pseudomonas, Acinetobacter, Burkholderia, Exiguobacterium, Pantoea, Rahnella, Rhodococcus and Serratia. They use plant growth promotion mechanisms including production of IAA, HCN, and ACC deaminase, phosphate solublization and biocontrol against plant pathogens such as Alternaria, Fusarium, Sclerotium, Rhizoctonia and Pythium.

• Preventive Nutrition and Food Science
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• 제3권2호
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• pp.143-151
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• 1998

Protein -surfactant interactions have been investigate by measuring ζ-potential of $\beta$-lactoglobulin-coated emulsion droplets and $\beta$-lactoglobulin in solution in the rpesenceof surfactant, with particular emphasis on the effect of protein heat treatment(7$0^{\circ}C$, 30min). When ionic surfactant (SDS or DATEM) is added to the protein solution, the ζ-potential of the mixture is found to increase with increasing surfactant concentration, indicating surfactant binding to the protein molecules. For heat-denatured protein,it has been observed that the ζ-potential tends to be lower than that of the native protein. The effect of surfactant on emulsions is rather complicated .With SDS, small amounts of surfactant addition induce a sharp increase in zeta potential arising from the specific interaction of surfactant with protein. With further surfacant addition, there is a gradual reductio in the ζ-potential, presumably caused by the displacement of adsorped protein (and protein-surfactant complex) from the emulsion droplet surfac by the excess of SDS molecules. At even higher surfactant concentrations, the measured zeta potential appears to increase slightly, possibly due to the formation of a surfactant measured zeta potential appears to increase slightly, possibly due to the formation of surfactant micellar structure at the oil droplet surface. This behaviour contrastswith the results of the corresponding systems containing the anionic emulsifier DATEM, in which the ζ-potential of the system is found to increase continuously with R, particularly at very low surfactant concentration. Overall, such behaviour is consisten with a combination of complexation and competitive displacement between surfactant and protein occurring at the oil-water interface. In addition, it has also been found that above the CMC, there is a time-dependent increase in the negative ζ-potential of emulsion droplets in solutions of SDS, possibly due to the solublization of oil droplets into surfactant micelles in the aqueous bulk phase.

• 한국산학기술학회논문지
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• 제19권10호
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• pp.16-23
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• 2018

하 폐수 슬러지 발생량의 꾸준한 증가로 인해 폐 슬러지의 효율적인 처리 기술개발이 요구되고 있다. 본 연구에서는 PEF (Pulsed Electric Fields) 기술을 활용하여 슬러지의 가용화를 통한 감량화 가능성을 평가하였다. PEF에 사용되는 스테인레스 재질의 전극에 테프론과 에폭시로 코팅한 후 활성슬러지 혼합액에 전계 펄스를 인가하여 전극 코팅에 따른 가용화 효율을 평가하였다. 또한 인가된 전압의 세기를 6, 12, 15 kV로 변화시켜 가며 가용화 정도를 평가하였다. 에폭시 코팅 전극에서는 MLSS, 용존성-COD, -TN, -TP를 분석한 결과 슬러지의 가용화가 발생하지 않은 것으로 나타났다. 그러나 테프론으로 코팅한 전극에서는 MLSS는 최대 9 % 감소하였고 MLVSS 역시 최대 10 % 감소하였다. 또한 용존성-COD는 최대 496 % 증가하였다. 인가전압 6 kV 하에서는 가용화가 거의 발생하지 않았으나, 12 kV와 15 kV의 전압에서는 슬러지 가용화가 발생한 것으로 나타났다. 또한 슬러지 가용화가 발생한 12 kV와 15 kV의 전압에서는 코로나가 발생한 것으로 보아 슬러지 가용화는 코로나에 의해 유도되었으며, 코로나가 발생하는 임계전압이 존재하는 것으로 판단되었다. 결론적으로 PEF의 인가전압과 적절한 코팅제를 선택하여 코로나 발생을 제어함으로써 슬러지의 가용화를 유도할 수 있음을 확인하였다.

• Korean Chemical Engineering Research
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• 제55권3호
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• pp.369-378
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• 2017

혈관 내피세포 성장인자(Vascular endotherial growth factor, VEGF)는 혈관 투과율 조절이나 혈관 생성에 관련된 단백질로 임상용으로 쓰일 가능성이 높다. 이 단백질은 고순도와 고효율로 상업적으로 대량생산이 필요하다. 유비퀴틴 융합 단백질로 온화한 조건에서 용해시키기 위해 다양한 조건을 연구하였고, pH와 변성제 변화를 시도하였다. BL21 (DE3) 대장균 숙주세포에서 pET28-a 벡터를 사용하여 재조합 대장균을 제조하여, 20 L의 회분식 배양으로 14 g/L농도의 세포배양을 하였다. 발효 후UBP1 효소 분해와 재접힘 단계를 포함한 4단계의 크로마토그래피 공정으로 구성된 정제공정으로 VEGF를 정제하였다. 유비퀴틴 융합단백질로 2 M 요소와 pH10 온화한 조건에서 VEGF의 정제가 가능하였다. 2번의 Ni-affinity 크로마토그래피컬럼을 이용하여 고효율의 재접힘과 이합체화 공정을 수행하였다. DEAE (Diethyl Amino Ethyl) 음이온 교환 컬럼을 통하여 변형체(multimeric, misfolded)단백질과 endotoxin을 제거 할 수 있었다. 젤 여과 크로마토그래피를 이용하여 dimer와 monomer를 분리 하여 이합체화 VEGF를 제조하였다. 최종 VEGF의 특성분석을 SDS-PAGE (Soidum Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis) 전기영동, RP-HPLC (Reversed Phase High Performance Liquid Chromatography)으로 하여 순도 97% (RP-HPLC기준)를 얻었다.