• Journal of Photoscience
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• 제9권3호
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• pp.75-79
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• 2002

Solubility of carbon tetrachloride ($CCl_4$) in water increases appreciably in presence of $\beta$-cyclodextrin ($\beta$CD). $CCl_4$ is a very good quencher of 1-naphthol (1ROH) fluorescence. By studying the quenching of fluorescence of 1ROH included in $\beta$CD cavity, it was found that there is an increase in the availability of $CCl_4$ around $\beta$CD in the aqueous medium. This could help to rationalize the enhanced solubility of $CCl_4$.

• 생명과학회지
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• 제4권3호
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• pp.92-101
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• 1994

With the rapid development of bioorganic chemistry recently, a field of artificial enzymes has a great concern from the industrial point of view. A number of possibilities now exist ofr the construction of artificial enzymes. They must posses two structural entities, a substrate-binding site and a catalytically effective site. It has been found that producing the facility for substrate binding is relatively straightforward but catalytic sites are somewhat more difficult. Therefore, synthetic catalysts do not yet match all the properties of an enzyme, however, the design of catalysts has lead to very powerful effects. This article reviews the existing literature on the modeling of artificial enzymes using cyclodextrin, modified cyclodextrin and crown compounds.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.399.2-399.2
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• 2002

Capillary electrophoretic direct chiral separation method is described for the determination of the absolute configuration of chiral aromatic acids, The enantiomeric separation was achieved by capillary electrophoresis using HP $\beta$-cyclodextrin (CD) as the chiral selector. The effect of CD concentration was investigated to optimize the chiral separation and resolution. When applied to microbial culture fluid. the present method allowed positive identification of chiral aromatic acids and their chirality as well.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.400.1-400.1
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• 2002

Because of the differences in pharmacological properties between enantiomers of chiral acidic non-steroidal antiinflammatory drugs (NSAIDs) in human body. accurate determinations of their optical purities have been in great need. An efficient capillary electrophoretic (CE) profiling method was developed for the enantioseparation of NSAIDs. Capillary electrophoretic conditions were optimized using TM$\beta$-cyclodextrin as the chiral selectors under MES buffer. (omitted)

• 대한화학회지
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• 제53권4호
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• pp.399-406
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• 2009

금속콜로이드에 흡착된 4-biphenyl acetonitrile(BPAN)을 $\alpha$-cyclodextrin($\alpha$-CD)으로 포접시킴으로 써 흡착배향을 변화시킬 수 있는지 여부를 알아보기 위하여 형광분광법을 이용하여 연구를 수행하였다. Au와 Ag 콜로이드 표면에 BPAN이 직접 흡착되는지 확인하기 위하여 온도증가에 따른 형광의 소광을 관찰하였다. 흡착이 이루어진 BPAN은 금속콜로이드의 종류에 상관없이 $\alpha$-CD와 포접화합물을 형성함을 발견하였으며 Benesi-Hildebrand 도시로부터 Au와 Ag에 흡착된 BPAN과 $\alpha$-CD의 포접화합물에 대한 형성 상수가 각각 32 $M^{-1}$과 13 $M^{-1}$인 것을 알아냈다. Au와 Ag 두 금속콜로이드에 흡착된 분자의 유사한 거동으로부터 $\alpha$-CD를 이용하여 분자의 흡착배향을 변화시킬 수 있음을 알게 되었다.

• Bulletin of the Korean Chemical Society
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• 제25권2호
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• pp.216-220
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• 2004

${\beta}$-CD and CM- ${\beta}$-CD as chiral NMR shift agents were used to resolve the enantiomers of noradrenaline (NA). The stoichiometry of each complex formed between the CDs and the enantiomers of NA was found to be 1 : 1 through the continuous variation plots. The binding constants (K) of the complexes were determined from $^1H$ NMR titration curves. This result indicated that both ${\beta}$-CD and CM- ${\beta}$-CD formed the complexes with the S(+)-NA more preferentially than its R(-)-enantiomer. The K values for the complexes with ${\beta}$-CD ($K_{S(+)}$ = 537 $M^{-1}$ and $K_{R(-)}$ = 516 $M^{-1}$ was larger than those with CM- ${\beta}$-CD ($K_{S(+)}$ = 435 $M^{-1}$ and $K_{R(-)}$ = 313 $M^{-1}$), however, enantioselectivity (${\alpha}$) of S(+)- and R(-)-NA to CM- ${\beta}$-CD ( ${\alpha}$ = 1.38) was larger than that to ${\beta}$-CD ( ${\alpha}$ = 1.04), indicating that CM- ${\beta}$-CD was the better chiral NMR solvating agents for the recognition of the enantiomers of NA. Two dimensional rotating frame nuclear Overhauser enhancement spectroscopy (ROESY) experiments were also performed to explain the binding properties in terms of spatial fitting of the NA molecule into the macrocyclic cavities.

• 한국환경보건학회지
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• 제28권5호
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• pp.65-70
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• 2002

Recently, surfactants were frequently used in order to desorb the hydrophobic organic compounds (HOCs) from soil and to enhance the bioavailability. Among them, -cyclodextrin ($\beta$-CD) is one of those. This study was performed to investigate the binding characteristics between benzene and $\beta$-CD and to examine the bioavailability of benzene. First, we investigated binding characteristics between benzene and $\beta$-CD in water and water/soil system. Then, we examined the effect of $\beta$-CD on the biodegradation of benzene in water and water/soil system. Experimental results on the binding characteristics showed that $\beta$-CD resulted in an efficient complex formation with benzene. As -CD concentration increased, the benzene concentration complexed with $\beta$-CD rapidly increased to 30-40% initial benzene added, and reached the equilibrium. We also investigated the effect of $\beta$-CD on the desorption of benzene from soil in the water/soil system. As $\beta$-CD concentration increased, benzene concentration desorbed into water increased up to 90%. How-ever, in its application to biodegradation of benzene in water and water/soil system, the biodegradation rate of benzene did not improved in the presence of $\beta$-CD compared with in the absense of $\beta$-CD. This result indicated that $\beta$-CD was more preferentially used as a carbon source than benzene. Therefore, for remediation of benzene contaminated soils, $\beta$-CD can be used as a surfactant to desert benzene from soil, and then ex-situ chemical treatment can be applied for the remediation.

• 한국축산식품학회지
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• 제29권5호
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• pp.566-572
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• 2009

This study was designed to elucidate the quantities of milk nutrients entrapped during cholesterol removal from milk by crosslinked $\beta$-cyclodextrin ($\beta$-CD, 0.4~1.2%, w/v) and to evaluate the amounts of the residual $\beta$-CD in cholesterol-reduced milk treated by crosslinked $\beta$-CD. The content of lactose in the control milk (without treatment by crosslinked $\beta$-CD) was 4.86%, and the amounts of lactose entrapped by crosslinked $\beta$-CD ranged from 0.00 to 0.03%. The total amounts of the entrapped short-chain free fatty acid (FFA) and free amino acid (FAA) ranged from 0.03 to 0.09 ppm and from 0.28 to $0.71{\mu}mol/mL$, respectively. The amounts of the entrapped water-soluble vitamins (L-ascorbic acid, niacin, thiamine and riboflavin) ranged from 0.02 to 0.05 ppm, 0.01 to 0.06 ppm, 0.00 to 0.06 ppm and 0.01 to 0.06 ppm, respectively. The entrapped amounts of lactose, short-chain FFAs, FAAs and water-soluble vitamins were not remarkably affected by the concentrations of crosslinked $\beta$-CD (0.4~1.2%, w/v). Only very small amounts of residual $\beta$-CD in the cholesterol-removed milk were measured (1.22~3.00 ppm). Based on the data obtained from the present study, it was concluded that the amounts of entrapped nutrients were negligible during cholesterol removal from milk by crosslinked $\beta$-CD, and only trace amounts of residual $\beta$-CD were present in cholesterol-removed milk.

• Journal of Microbiology and Biotechnology
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• 제8권2호
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• pp.152-157
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• 1998

To analyze the role of the C and D domains in the cyclization activity of cyclodextrin glucanotransferase (CGTase), two plasmids, pKB1ΔC300 and pKB1ΔD96, were constructed in which DNA regions encoding 100 and 32 amino acids, respectively, from the C and D domains of B. stearothermophilus NO2 CGTase were deleted. The mutated CGTase from the pKBlΔC300 produced much lower amounts of ${\alpha}$-, ${\beta}$-, and $\gamma$-cyclodextrin (CD) than the parental CGTase. However, the mutated CGTase from the pKBlΔD96 showed a similar production pattern of CDs to wild-type CGTase. The production ratios of the ${\alpha}$-, ${\beta}$- and $\gamma$-CDs were not affected by the deletions, when compared to those of parental CGTase. The optimum temperature of the mutated CGTase from the pKBlΔC300 was decreased from $60^{\circ}C$ to $55^{\circ}C$. The optimum pH of the mutated CGTase from the pKB1D96 was shifted from 6.0 to 7.0. The thermostability of the two mutant CGTases were not changed. From these results, it is suggested that the C and D domains are not related to cyclization activity directly because mutant-enzymes deleted C or D domains still possessed their activity. However, they are important for other enzymatic properties such as productivity and pH optimum as a partition of CGTase tertiary structure.

• Journal of Pharmaceutical Investigation
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• 제27권1호
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• pp.11-14
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• 1997

This laboratory has recently reported the solubility and in vivo absorption enhancement of diclofenac sodium by ${\beta}-cyclodextrin$ complexation. The acute gastroduodenal mucosa injury provoked by administration of 34 mg/kg and 68 mg/kg of a diclofenac sodium (DS) and equivalent dose of new formulation [diclofenac sodium-beta-cyclodextrin complexation$(DS-{\beta}-CD)$] was evaluated and compared. Microscopic examinations, performed after 18-hrs treatment, demonstrated that $DS-{\beta}-CD$ was less gastrolesive than DS. The drop in gastrophy after a single dose of the assigned drug was considerably greater for DS than for $DS-{\beta}-CD$, which registered similar values to control. Since gastrophy is an expression of the anatomy-functional integrity of the gastric barrier, the results indicate that $DS-{\beta}-CD$ exerts less direct acute damage on the gastric mucosa. Therefore, when administered short-term, $DS-{\beta}-CD$ appears to be less gastrolesive than the standard DS formulation.