• 대한화학회지
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• 제45권1호
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• pp.61-66
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• 2001

효소결정을 격자화하여 안정화한 CLEC은 생촉매제로써 뿐아니라 효소센서로 이용할 수 있다. 전자이동 중개체로 사용되고 있는 PMS는 HLADH에 대하여 가장 효율적인 전자이동 활성도를 가졌다. NQS는 PMS에 비하여 52%, phenothiazine은 37%, ferrocene aldehyde는 3 5%의 전자 이동 활성도를 가졌다. HLADH는 용액상태에서 PMS, NQS에 대하여 매우 불안정하였다. 반면에 HLADH-CLEC은 용액상태에서 불안정했던 PMS, NQS, ferrocene aldehyde에 대하여 매우 안정하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.167-179
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• 2005

Chiral epoxides are highly valuable intermediates, used for the synthesis of pharmaceutical drugs and agrochemicals. They have broad scope of market demand because of their applications. A major challenge in modern organic chemistry is to generate such compounds in high yields, with high stereo- and regio-selectivities. Epoxide hydrolases (EH) are promising biocatalysts for the preparation of chiral epoxides and vicinal diols. They exhibit high enantioselectivity for their substrates, and can be effectively used in the resolution of racemic epoxides through enantioselective hydrolysis. The selective hydrolysis of a racemic epoxide can produce both the corresponding diols and the unreacted epoxides with high enantiomeric excess (ee) value. The potential of microbial EH to produce chiral epoxides and vicinal diol has prompted researchers to explore their use in the synthesis of epoxides and diols with high ee values.

• 한국해양바이오학회지
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• 제1권1호
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• pp.9-21
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• 2006

Foods and related substances from diverse sources known to have a potential for disease risk reduction are called functional foods, while nutraceuticals are bioactive compounds isolated from food and sold in dosage form. Nutraceutical and functional food industries are rapidly growing in recent years and most of the cases development of these functional materials involves certain biotransformation processes. A number of bioactive compounds has been identified up to date and isolated from seafood related products through enzyme-mediated hydrolysis. The enzymatic bioconversion process require suitable biocatalysts and appropriate bioreactor systems to incubate byproducts with digestive enzymes. Membrane bioreactor technology is recently emerging for the development of bioactive compounds from seafood processing byproducts.

• 한국미생물·생명공학회지
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• 제27권3호
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• pp.184-190
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• 1999

To acquire an industrially useful biocatalyst for the enzymatic synthesis and production of various D-amino acid aminotransferase (D-AAT) activity. The enzyme activity was found from 110 strains of isolated thermophiles revealing its wide occurrence in thermophiles. Enzyme activity and thermal stability of the D-AAT producers were compared. Finally we have selected four thermophiles as producers of potent biocatalysts for the D-amino acid production; two thermophiles, Bacillus sp. Lk-1 and LK-2, having higher specific activity and two thermophiles, B. stearothermophilus KL-01 and Bacillus sp. KLS-01, having higher thermal stability than the D-AAT producers. Taxonomic and physiological characteristics of the four isolated thermophiles were described herein.

• 한국패류학회지
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• 제32권1호
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• pp.63-65
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• 2016

Carbonic anhydrase (CA), which is involved in shell formation processes in bivalves, is one of the major biocatalysts for carbon capture and storage. In this study we investigated CA activity in the total hemocytic proteins of five bivalves. The highest CA activity was observed in Scapharca broughtonii, which had more than twice the activity found in Crassostrea gigas. No CA activity was observed among the total hemocytic proteins of Pinctada fucata and Saxidomus purpuratus. The results suggest that marine invertebrates may provide a better source of CA, as an alternative to mammalian sources.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.159-162
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• 2005

In this paper, we report a novel technique for the manufacture of polymeric bar-coded strips having diverse characteristics such as sensing with biocatalysts using a microfluidic platform and 'on the fly' photopolymerization. This method is a very simple, cost-effective means for mass production, and diverse materials sensitive to hazardous environments such as enzymes, DNA, or antigens are expected to be immobilized stably, as the fabrication process does not need any hazardous environments. On the basis of this technology, we fabricated enzyme-immobilized barcoded strip for multiple bio-analysis.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권1호
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• pp.42-50
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• 2001

The activity of immobilized cell-support particle aggregates is influenced by physical and biochemical elements, mass transfer, and physiology. Accordingly, the mathematical model discussed in this study is capable of predicting the steady state and transient concentration profiles of the cell mass and substrate, plus the effects of the substrate and product inhibition in an immobilized cell-support aggregate. The overall mathematical model is comprised of material balance equations for the cell mass, major carbon source, dissolved oxygen, and non-biomass products in a bulk suspension along with a single particle model. A smaller bead size and higher substrate concentration at the surface of the particle, resulted in a higher supply of the substrate into the aggregate and consequently a higher biocatalyst activity.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권1호
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• pp.1-8
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• 2003

With current developments in enzyme-catalyzed reactions and techniques available for rational redesign of natural biocatalysts, the enzymatic biosynthesis can become one of the most valuable Synthetic methods. Enzymatic regioselective catalysis in organic media has played a key role in pursuing asymmetric synthesis for active chiral compounds. Here, we shortly do-scribe some historical issues of the rapidly growing area, enzymatic catalysis in synthetic organic chemistry and then review researches that have been carried out in the regioselective enzymatic catalysis for the past two decades. An application of this technology to the modification of some potential target drug co m pound will be adios presented.

• Journal of Microbiology and Biotechnology
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• 제24권1호
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• pp.44-47
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• 2014

A biotransformation approach using microbes as biocatalysts can be an efficient tool for the targeted modification of existing antibiotic chemical scaffolds to create previously uncharacterized therapeutic agents. By employing a recombinant Streptomyces venezuelae strain as a microbial catalyst, a reduced macrolide, 10,11-dihydrorosamicin, was created from rosamicin macrolide. Its chemical structure was spectroscopically elucidated, and the new rosamicin analog showed 2-4-fold higher antibacterial activity against two strains of methicillin-resistant Staphylococcus aureus compared with its parent rosamicin. This kind of biocatalytic approach is able to expand existing antibiotic entities and can also provide more diverse therapeutic resources.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.147-150
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• 2004

Permeabilization is known to overcome cell membrane barriers of whole cell biocatalysts. The use of organic solvents is advantageous in terms of cost, simplicity, and efficiency. In this study, Ochrobactrum anthropi SY509 was permeabilized with various organic solvents. Treatment with organic solvents resulted in lower permeability barriers due to falling out lipids of the cell membrane. Therefore, permeabilized cells showed higher enzyme activity with no cell viability. Among various organic solvents, 0.5% (v/v) chloroform was selected as the most efficient permeabilizing reagent. Changes in the cell membrane structure were observe d and the residual amounts of phospholipids of the cell membrane were measured to investigate the mechanism of the improved permeability.