• KSBB Journal
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• v.13 no.6
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• pp.693-699
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• 1998

The relationship between bioluminescence of immobilized Photobacterium phosphoreum and toxic substances was investigated to monitor toxic substances in aqueous solution. The sodium alginate was used as an immobilization matrix. A bioluminescence intensity was maximum when OD660 for cell concentration were between 1.0 and 1.2 and the biolumescence was stable at the pH range of between 6.0 and 8.0. The optimum concentration of alginate for immobilization was found to be 5.0%(w/v) in which dilution was carried out with 2.5%(w/v) NaCl solution that is an optimum environmental condition for the growth of P. phosphoreum. The bioluminescence intensity responded against the toxic substances was proportional to the concentration and a regression curve were established with linearity by using specific bioluminescence reduction rate and Gamma values. It was also found that the response was very rapid and sensitive. The response with such rapidity and sensitivity is a very important factor for the real time monitoring. The immobilized cells showed higher sensitive response to the toxic substances than free cells.

• BMB Reports
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• v.32 no.1
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• pp.98-102
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• 1999

Since carbohydrates are major mediators in cell-to-cell adhesion and communication, the development of specific and strong binders against them could generate promising therapeutics. As the first step towards that goal, sugar molecules have to be immobilized to be used as an affinity matrix. The amino functionality in sugar is the most active nucleophile for the immobilization, if the amino group is available. An alternative and general method is to use the hydroxyl group as a direct nucleophile, but the quantitation of immobilized hydroxyl groups is not easily done. To overcome this limitation, we have developed a method to immobilize various isomers of monosaccharides with p-nitrophenyl groups to the beads by using their hydroxyl groups. It was found that the amount of immobilized sugar was independent of the structure of the sugar, but was dependent on the number of hydroxyl groups. We also developed a sensitive method to quantify the amount of immobilized sugar at the picomolar scale by utilizing commercially available glycosidases to release a sensitive reporter molecule, p-nitrophenol, and detect it by HPLC. This new technique would allow a facile quantitation method for immobilized sugar molecules, which could be used as the affinity matrix to develop strong binders against biologically important sugars.

• Microbiology and Biotechnology Letters
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• v.22 no.3
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• pp.296-303
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• 1994

An immobilized Trigonopsis variabilis cells having an high activity of D-amino acid oxidase(DAO) was used to convert CPC into GL-7-ACA. The optimal pH of the reaction system was 8.0-8.5, and the optimal temperature was 40$\circ$C. When immobilized cell was used repeatedly in semi-batchwise reaction, the system retained 80% of the initial activity after used of 12 times for over 12 hours. The storage stability of the immobilized cell was maintained for 30 days at 4$\circ$C. The CPC concentration for the maximal reaction rate was about 30 mM and 40 mM for free and immobilized cells, respectively. Substrate inhibition of CPC concentration more than 50 mM was overcomed by 20~25% by immobilization. Pure oxygen supply into reaction system was most efficient in D-amino acid oxidase reaction. Continuous conversion to GL-7-ACA from CPC has been developed with an bioreactor system containing immobilized T variabilis cells. By opera- tion of the reactor for 5 hours, the average conversion yield of >80% and GL-7-ACA production of 40~45 mM per hour could be obtained.

• The Journal of Korean Physical Therapy
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• v.10 no.2
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• pp.71-76
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• 1998

Twelve Spraque-Dawley healthy male rats(average weight ; 250g)were used to study the morphological changes of mitochondria, myofibril, muscle cell nucleus, triad. They were devided into 3 groups : normal daily activity (Group 1), 2weeks immobilization (Group 2), 4 weeks immobilization(Group 3). Left ankle of Group 2 and 3 were immobilized with plaster cast in $65^{\circ}$ plantarflexed position. The gastrocnemius were removed from 12 rats. Muscle fibers were observed electronmicroscopically by double staining with uranyl acetate and lead citrate, All the variables of Group 2 and 3 that selected in this study were significantly decreased when decreased with control value (p<.05) but also muscle fibers showed extensive damage, characterized by irregularity of mitochondrias and wide separation of myofibrils. irregularity and thinness of myofilaments and abnormal shape of muscle cell nucleus and unclear triad. Especially, sarcomere length of Group 3 were singnificantly decreased when compared with Group 2(p<.01).

• The Korean Journal of Mycology
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• v.11 no.3
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• pp.109-114
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• 1983

${\beta}-Galactosidase$ activity of Aspergillus phoenicis was studied using ONPG and lactose as substrate. It increased monotonically during the exponential growth phase and dropped rapidly at the beginning of the stationary one. It exhibited high tolerable temperature and acidic optimal pH which provides certain advantages from the industrial view point. Enzyme of ${\beta}-galactosidase$ had more subsrate affinity for ONPG than for lactose and its apparent maximum activity was also higher with the former as substrate. Activity of this enzyme depended upon the conditions of immobilization. Optimum crosslinking reaction was occurred at pH 7.2 and 0. 35 vol. % of glutaraldehyde concentration.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.429.1-429.1
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• 2014

We present a method of surface functionalization of a single layer graphene for linking and detecting MDA-MB-231 human breast cancer cell. The methodology is done by utilizing 1-pyrenebutanoic acid and succinimidyl ester for immobiling CD44 antibodies. This work shows that the single layer graphene is an efficient fixing substance to capture the MDA-MB-231 human breast cancer cell, selectively. The immobilization method of the cancer cell on the graphene layer will be an effective cell counting system. Moreover usage of the linking with non-covalent bonding is expected to develope a sensor scheme of electrical cell-detecting diagnosis system.

• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.209-212
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• 1985

The cell density and packing characteristics of Escherichia coli immobilized in a dual hollow fiber bioreactor consisting of outer silicone membrane for oxygen transport and three inner isotropic polypropylene hollow fibers for substrate transport were investigated. The cells have grown forming the layer like animal tissue in a nearly 100％ packing density. The dry biomass density was 550g/liter of void volume for cell growth, which was the highest among the biomass densities ever reported.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.6
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• pp.1585-1593
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• 2005

The genetic effects of restraint stress challenge on HPA axis and the therapeutic effect of Boshimgeonbi-tang on the stress were studied with cDNA microarray analyses, RT-PCR on hypothalamus using an immobilization-stress mice as an animal model. Male CD-1 mice were restrained in a tightly fitted and ventilated vinyl holder for 2hrs once a day, and this challenge was repeated for seven· consecutive days. In the change of body weight it showed that the Boshimgeonbi-tang is effected recovery on weight loss caused by the immobilization-stress. Seven days later, total RNA was extracted from the organs of the mouse, body-labeled with $CyDye^{TM}$ fluorescence dyes and then hybridized to CDNA microarray chip. Scanning and analyzing the array slides were carried out using GenePix4000 series scanner and GenePix $Pro^{TM}$ analyzing program, respectively. The expression profiles of 109 genes out of 6000 genes on the chip were significantly modulated in hypothalamus by the immobilization stress. Energy metabolism-, lipid metabolism-, apoptosis-, stress protein, transcriptional factor, and signal transduction-related genes were transcriptionally activated whereas DNA repair-, protein biosysthesis-, and structure integrity-related genes were down-regulated in hypothalamus. The 58 genes were up-regulated by the mRNA expression folds of 1.5 to 7.9. and the 51 genes were down-regulated by 1.5 - 5.5 fold. The 11 genes among them were selected to confirm the expression profiles by RT-PCR. The mRNA expression levels of Tnfrsf1a (apoptosis), Calm2 (cell cycle), Bag3 (apoptosis), Ogg1 (DNA repair), Aatk (apoptosis), Dffa (apoptosis), Fkbp5 (protein folding) were restored to the normal one by the treatment of Boshimgeonbi-tang.

• Journal of Microbiology and Biotechnology
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• v.7 no.5
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• pp.345-351
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• 1997

An aqueous/organic two-phase reaction system was applied to the production of catechol using immobilized resting cells of Pseudomonas putida CY 400. Water/ethyl ether system was used because of high partition coefficient of catechol and thus to reduce the product inhibition and degradation. Among the tested immobilization carriers, polyacrylamide gel gave the highest catechol productivity. The immobilization seemed to protect the cells against solvent toxicity. From the simulation of reaction conditions based on two-phase models, it was found that there was an optimum acetate concentration at fixed benzoate and cell concentrations for the catechol productivity. A lower phase volume ratio (lower fraction of organic phase) gave a higher productivity. However, the substrate conversion was low at low phase volume ratio.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.411.2-411.2
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• 2014

The design of DNA nanostructures is of fundamental importance, the intrinsic value of DNA as a building-block material lies in its ability to organize other bio-molecules with nanometer-scale spacing. Here, we report the fabrication of DNA scaffolds with nano-pores (<10 nm size) that formed easily without the use of additives (i.e., avidin, biotin, polyamine, or inorganic materials) into large-scale structures by assembling DNA molecules at near room temperature ($30^{\circ}C$) and low pH (~5.5). Protein immobilization results also confirmed that a fibronectin (FN) proteins/large scale DNA scaffolds/aminopropylytriethoxysilane (APS)/SiO2/Si substrate with high sensitivity formed in a well-defined manner. The DNA scaffolds can be applied for use with DNA-based biochips, biophysics, and cell biology.