• Journal of Pharmaceutical Investigation
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• v.27 no.4
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• pp.265-269
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• 1997

An inclusion complex of muscone with ${\beta}-cyclodextrin$ (CD), as a solid form of muscone, was prepared to increase the solubility of muscone. The molar ratio of muscone to ${\beta}-CD$ in complex was in the range of $1:1{\sim}1:5$ when prepared by freeze-drying method. The interaction of muscone with ${\beta}-CD$ in solid state was investigated by Infrared (IR) spectroscopy and differential scanning calorimetry (DSC). IR and DSC studies between $muscone-{\beta}-CD$ inclusion complex and physical mixture showed that $muscone-{\beta}-CD$ inclusion complex was prepared stably. From the amount of muscone incorporated in the inclusion complex, it was found that the molar ratio of muscone : ${\beta}-CD$ was 1:1. Relative spatial position of muscone and ${\beta}-CD$ was observed by Hyperchem molecular modelling program.

• Analytical Science and Technology
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• v.15 no.2
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• pp.115-119
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• 2002

The formation of inclusion complexes between cyclodextrin(CD) and Congo red was studied by spectrophotometric methods at various temperatures. The cavity sizes are 0.49 nm, 0.62 nm for $\alpha$-and $\beta$-CD, respectively. Therefore, $\alpha$-CD was not found to form an inclusion complex with Congo red due to steric hinderance. In the $\beta$-CD use two $\beta$-CD molecules formed an inclusion complex with one molecule of Congo red, from the slope of the S-shaped curve increased. Two prominent isosbestic points appear at 346 nm and 478 nm. The formation constants were decreased with the increasing temperatures, due to low binding energy between $\beta$-CD and Congo red. The thermodynamic parameters were calculated from the plot of $lnK_f$ vs 1/T. The $\Delta$H, $\Delta$S and $\Delta$G were -50.73 kJ/mol, $-108.96J/K{\cdot}mol$ and -18.26 kJ/mol, respectively.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.465-471
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• 1997

The cyclodextrin glycosyltransferase (CGTase, EC 3.2.1.19) from Bacillus brevis CD162 was purified by precipitating with ammonium sulfate, DEAE-Sepharose CL-6B column chromatography and Sephadex G-150 column chromatography. The molecular mass and pI of the purified enzyme were estimated to be 74,000 and 6.3 by SDS-PAGE and isoelectric focusing, respectively. The purified enzyme was clearly identified as the CGTase by zymogram after SDS-PAGE. The optimum pH and temperature for the enzyme activity were 8.0 and $55^{\circ}C$, respectively. The enzyme was stable at the range of pH $5.5{\sim}9.0$, and up to $50^{\circ}C$. The amino acid sequence from the $NH_2-terminal$ of the purified CGTase was Ser-Val-Thr-Asn-Lys-Val-Asn-Tyr-Ser-Lys-Asp-Val-Ile-Tyr-Gln. The yields of the products from starch as the substrate were 1.3% for ${\alpha}-$, 33.9% for ${\beta}-$, and 9.7% for ${\gamma}-cyclodextrin$.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.4
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• pp.537-542
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• 2014

This study was carried out to optimize cholesterol removal in whole egg using crosslinked ${\beta}$-cyclodextrin (${\beta}$-CD) and to recycle the ${\beta}$-CD. Various factors for optimizing conditions were concentration of the ${\beta}$-CD, mixing temperature, mixing time, mixing speed and centrifugal speed. In the result of this study, the optimum conditions of cholesterol removal were 25% crosslinked ${\beta}$-CD, $40^{\circ}C$ mixing temperature, 30 min mixing time, 1,200 rpm mixing speed and $2,810{\times}g$ centrifugal speed. The recycling was repeated five times. The cholesterol removal was 92.76% when treated with the optimum conditions. After determining the optimum conditions, the recyclable yields of the crosslinked ${\beta}$-CD ranged from 86.66% to 87.60% in the recycling and the percentage of cholesterol removal was over 80% until third recycling. However, the cholesterol removal efficiency was decreased when the number of repeated recycling was increased. Based on the result of this study, it was concluded that the crosslinked ${\beta}$-CD was efficient for cholesterol removal in whole egg, and recycling is possible for only limited repeating times due to the interaction of the ${\beta}$-CD and egg protein.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.753-759
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• 2002

$\beta$-Cyclodextrin glucanotransferase ($\beta$-CGTase) was overproduced extracellularly using recombinant E. coli by transforming the plasmid pECGT harboring a secretive signal peptide. The $\beta$-CGTase gene of alkalophilic Bacillus firmus var alkalophilus was inserted into the high expression vector pET20b(+) containing a secretive pelB signal peptide, and then transformed into E. coli BL2l(DE3)pLysS. The optimum culture conditions fer the overproduction of $\beta$-CGTase were determined to be TB medium containing 0.5% (w/v) soluble starch at post-induction temperature of $25^{\circ}C$. A significant amount of $\beta$-CGTase, up to 5.83 U/ml, which was nine times higher than that in the parent strain B. firmus var. alkalophilus, was overproduced in the extracellular compartment. A pH-stat fed-batch cultivation of the recombinant E. coli was also performed to achieve the secretive overproduction of $\beta$-CGTase at a high cell density, resulting in production of up to 21.6 U/ml of $\beta$-CGTase.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1290-1294
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• 2004

The ${\beta}$-blockers possess at least one chiral center and the S(-)-enantiomer shows higher affinity for binding to the ${\beta}$-adrenergic receptors than antipode. The stability constants of acebutolol, celiprolol, propranolol and terbutaline in the inclusion complexes with single-isomer heptakis (2,3-dimethyl-6-sulfato)- ${\beta}$-cyclodextrin (HDMS-${\beta}$-CD) were determined by capillary electrophoresis. The approximation and linear double reciprocal methods were adapted with comparable results. Among the ${\beta}$-blockers studied, propranolol had the lowest stability constant but the highest enantioselectivity, indicating that the magnitudes of the stability constants carried little information about enantioseparation. The magnitudes of enantioselectivities between the enantiomer pair were in the order of propranolol > celiprolol > terbutaline > acebutolol.

• Journal of Pharmaceutical Investigation
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• v.23 no.1
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• pp.11-18
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• 1993

Inclusion complex of ibuprofen with $2-Hydroxypropyl-{\beta}-cyclodextrin\;(HP-{\beta}-CD)$ in aqueous solution and in the solid state was evaluated by the solubility method and the instrumental analysis such as infrared spectroscopy, thermal analysis and x-ray diffractometry. The aqueous solubility of ibuprofen was increased linearly with the increase in the concentration of $HP-{\beta}-CD$, showing an $A_L$ type phase solubility diagram. The results showed that the dissolution rate of ibuprofen was significantly increased by complexation with $HP-{\beta}-CD$. $Ibuprofen-HP-{\beta}-CD$ complex enhanced the mean plasma concentration levels and the area under plasma concentration-time curve after oral administration compared to those of the drug alone. It is concluded that the complex of ibuprofen with $HP-{\beta}-CD$ increases the dissolution rate and improves the bioavailability of the ibuprofen by the formation of a water-soluble complex.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.325-328
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• 1998

$\beta$-cyclodextrin($\beta$-CD)은 cycloheptaamylose라고도 하며 $D^{＜+>}$-glucopyranose 단위체가 7개 연결된 구조를 가지고 있다(Fig. 1). $\beta$-CD는 고리모양으로 되어있는데 외부는 친수성, 내부는 소수성을 갖는다[1]. 고리내 부가 소수성인 이유는 내부에 소수성기인 C-H그룹과 glucosidic oxygen만이 존재하기 때문이다[1].(중략)

• Journal of Pharmaceutical Investigation
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• v.27 no.1
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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.

• Journal of Pharmaceutical Investigation
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• v.24 no.2
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• pp.85-94
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• 1994

Inclusion complexes of ketoconazole (KT) with ${\alpha}-$, ${\beta}-cyclodextrin$ (CD) and dimethyl-${\beta}-cyclodextrin$ $(DM{\beta}CD)$ in a molar ratio of 1:2 were prepared by freeze-drying and solvent evaporation methods. The interactions of KT with ${\alpha}-CD$, ${\beta}-CD$ and $DM{\beta}CD$ in aqueous solution and in solid state were investigated by solubility study, infrared (lR) spectroscopy and differential scanning calorimetry (DSC). The stability constant of $KT-DM{\beta}CD$ inclusion complex (lC) was found to be the largest among three inclusion complexes. Clear differences in IR spectra and DSC curves were observed between inclusion complexes and physical mixtures (PM) of KT-CDs. It was also shown by IR spectra and DSC curves that solvent evaporation method might be. superior to the freeze-drying method in preparing the inclusion complexes of KT-CDs. The dissolution rate of KT was markedly increased by inclusion complex formation with CDs in the buffer solution at pH 4.0 and pH 6.8. The mean dissolution time (MDT,min), which represents the rapidity of dissolution, was in the order of $KT-DM{\beta}CD$ IC (3.20) < $KT-{\beta}-CD$ IC (4.36) < $KT-{\alpha}-CD$ IC (6.99) < $KT-{\alpha}-CD$ PM (17.46)< $KT-{\beta}-CD$ PM (19.36) < $KT-{\beta}-CD$ PM (28.53). The dissolution rates of KT-CD ICsprepared by solvent evaporation method were faster than those of KT-CD ICs prepared by freeze-drying method.