• Proceedings of the Botanical Society of Korea Conference
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• 1995.06a
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• pp.79-90
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• 1995

Production of a cardiac glycoside, digoxin, by 12$\beta$-hydroxylation from digitoxin was studied in plant cell suspension cultures of Digitalis lanata. In order to increase the conversion yield, various culture conditions including immobilization were investigated and optimized. Since digoxin was released in the medium temporarily and converted further into a glucosylated product, deacetyllanatoside C, in situ adsorption of digoxin was employed to recover the product continuously. Amberlite resin XAD-8 showed the best adsorption characteristics for digoxin among the examined resins, and an integrated process was developed to increase the productivity. In addition, it was found that the utilization of $\beta$-cyclodextrin to entrap digoxin during the culture enhanced the biotransformation yield significantly.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.302-302
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• 1994

오메프라졸의 산 불안정성을 개선하기 위하여 신규 합성한 오메프라졸 cholestyramin resin 염 복합체와 오메프라졸 hydroxypropyl-$\beta$-cyclodextrin (HP-$\beta$-CD) 포접화합물의 약효를 검색하였다. 생체외 실험 (in vitro test)으로 H$^{+}$/K$^{+}$-ATPase 활성도 저해효과를 검토하였으며 생체내 실험 (in vivo test)으로 Shay 결찰법에 의한 위산분비 억제효과에 대한 실험을 실시하였다. 오메프라종 염 복합체와 오매프라졸 포접화합물은 1$\times$$10^{-5}$-1$\times$$10^{-3}$M농도 범위에서 용랴의존적으로 H$^{+}$K$^{+}$-ATPase 활성을 억제시켰으며 $IC_{50}$/치는 오메프라졸 결과와 유사하였다. 셍체네 실험에서는 오메프라졸 HP-$\beta$-CD 포접화합물이 오메프라졸과 그 resin염복합체보다 위액분비량, 펩신 활성도에 대한 $IC_{50}$/치가 낮았으며 이는 생체내에서 포접 화합물이 오메프라졸의 안정성을 증가시킴으로서 위산분비 억제효과를 증가시킨것으로 사료된다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.118-118
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• 1997

Solid dispersions were used to increase the dissolution rate of biphenyl dimethyl dicarboxylate (DDB) in water, with the ultimate goal of optimizing its bioavailability when incoporated into pharmaceuticals. Carriers used were Kollidon 30, Kollidon VA 64, 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD), sodium salicylate or sodium benzoate. DDB solid dispersions were prepared at drug to carrier proportions ranging from 1 : 5 to 1 : 20 (w/w) by solvent evaporation method. DDB tablets (7.5 mg) were prepared by compressing the powder mixture composed of solid dispersions, lactose, corn starch, crospovidone and magnesium stearate using a single-punch press. DDB capsules (7.5 mg) were prepared by filing the mixture into empty hard gelatin capsules (size #1). Dissolution studies of DDB from powdered solid dispersions, tablets and capsules were performed in 900 $m\ell$ of water at 100 rpm and 37$^{\circ}C$ by the paddle method. The dissolved amount was assayed by HPLC and expressed as the mean(%)of three determinations.

• Journal of Microbiology and Biotechnology
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• v.8 no.6
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• pp.710-713
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• 1998

A material with the same high performance liquid chromatography (HPLC) retention profile as authentic ascorbic acid 2-Ο-$\alpha$-glucoside (AA-2G) was detected in kimchi. This material was identified as AA-2G by testing its susceptibility to $\alpha$-glucosidase hydrolysis, the HPLC profile, and through the elementary analysis. Among several strains of bacteria isolated from fermented kimchi, four strains could produce cydodextrin glucanotransferase (CGTase) which catalyzes the transglucosylation reaction of ascorbic acid. By using starch as the glycosyl donor, AA-2G was produced as the major product through this reaction.

• Macromolecular Research
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• v.14 no.2
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• pp.214-219
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• 2006

Cast Nafion-based composite membranes containing different amounts of organic, nanorod-shaped polyrotaxane were prepared and characterized, with the aim of improving the properties of polymer electrolyte membranes for direct methanol fuel cell applications. Polyrotaxane was prepared using the inclusion-complex reaction between ${\alpha}$-cyclodextrin and poly(ethylene glycol) (PEG) of different molecular weights. The addition of polyrotaxane to Nafion changed the morphology and reduced the crystallinity. The conductivity of the composite membranes increased with increasing polyrotaxane content up to 5 wt%, but then decreased at higher polyrotaxane contents. Well-dispersed, organic polyrotaxane inside the membrane can provide a tortuous path for the transport of methanol, as the methanol permeability depends on the aspect ratio of polyrotaxane, which is controlled by the molecular weight of PEG. All of the Nafion-based, polyrotaxane composite membranes showed a higher selectivity parameter than the commercial Nafion films did.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.91-92
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• 2006

The fine-tuned dendrons provide unique supramolecular self-assemblies in various environments such as in water, organic media, and solid-liquid interfaces. They form nanotubes, vesicles, thin films, columns, lamellar nanoribbons depending on the condition of self-assembly process. Unique characteristics of self-assembly of the amide dendrons are described. In addition, elucidation of the structural correlation between the building blocks and the assemblies, stabilization of assembled structure, and transformation of supramolecular assemblies by using external stimuli. Particular emphasis is placed on the formation of cyclodextrin-covered organic nanotubes derived from self-assembly of amide dendrons and their supramolecular transformation. Finally, unique biosensory characteristics of the self-assembled nanotubes will be discussed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.1
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• pp.67-71
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• 2001

Most of the Cyclodextrin glucanotransferase (Gtases) which have been produced from B. subtilis were found to be excreted from the cells during cultivation. Immobilized whole cell CGTase from B. subtilis was prepared by encapsulating the broth solution which had been concentrated ten times with a rotary vacuum evaporator. Cyclization activity of CGTase was reduced by about 10% during the concentrating process, however, its transglycosylation activity, to convert xylitol to glucosyl-xylitol, using dextrin as glucosyl donor, increased by a factor of 3 or 5.

• Journal of Pharmaceutical Investigation
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• v.15 no.3
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• pp.130-139
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• 1985

Inclusion compounds of suprofen with ${\alpha}-$ and, ${\beta}-cyclodextrins\;({\alpha}-CyD,\;{\beta}-CyD)$ were studied in comparison with suprofen alone and commercial suprofen capsules. Inclusion compound formations of suprofen with ${\alpha}-$, and ${\beta}-CyDs$ in aqueous solution and in solid state were confirmed by UV absorption, circular dichroism spectroscopies, IR spectroscopy, differential scanning calorimetry and X-ray diffraction measurements. Solid inclusion complexes were prepared by freeze-drying method, and their molar ratios were found to be 1 : 1. The dissolution rate of inclusion complexes of suprofen with CyDs was notably higher than that of suprofen alone.

• Journal of the Korean Society of Tobacco Science
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• v.25 no.2
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• pp.120-127
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• 2003

Cyclodextrin glucanotransferase (CGTase) from Bacillus stearothermophilus synthesized vanillin and ethyl vanillin monoglucoside, with a series of its maltooligoglucosides by transglycosylation with dextrin as a donor, and vanillin or ethyl vanillin as an acceptor. The monoglucoside formed from reaction mixture of vanillin or ethyl vanillin by the successive actions of CGTase and Rhizopus glucoamylase was isolated by extraction with n-butanol saturated with water and silica gel column chromatography. The structure of the isolated monoglucoside was identified as vanillin- $\alpha$ -D-glucoside and ethyl vanillin- $\alpha$ -D-glucoside, respectively, by FAB-MS, UV, IR, 1H-NMR, 13C-NMR spectra and products by hydrolysis with acid, $\alpha$ - and $\beta$ -glucosidases.

• Korean Journal Plant Pathology
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• v.13 no.2
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• pp.125-128
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• 1997

Reactions of Pseudomonas syringae pv. actinidiae to 95 carbon sources in a 96-well microplate (BiOLOG GN MicroPlateTM) were investigated. The bacterium used 9 carbon sources such as D-mannitol, sucrose, etc., but did not use 62 carbon sources such as $\alpha$-cyclodextrin, dextrin, etc. Based on the reactions, a user data base for identification of P. syringae pv. actinidiae was constructed in Biolog program (BiOLOG MicroLogTM 2 system). P. syringae pv. actinidiae isolates collected from kiwifruits could be identified automatically with high similarity using the user data base, which could diagnose rapidly and easily whether the tree was infected with bacterial canker or not.