• Polymer(Korea)
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• v.38 no.3
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• pp.338-350
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• 2014

Cellulose acetate (CA) fiber mats containing inclusion complexes of asiaticoside (AC) in 2-hydroxypropyl-${\beta}$-cyclodextrin ($HP{\beta}CD$) for potential usage as wound dressings were developed. The AC/$HP{\beta}CD$ complex-loaded CA fibers at various $HP{\beta}CD$ to AC molar ratios of 0.5, 1, and 2 were prepared in 90:10 v/v mixture of 80% (v/v) acetic acid and N,N-dimethylacetamide (DMAc) via electrospinning. The maximum released amounts of AC depended on the $HP{\beta}CD$ content and were much greater than those released from the AC-loaded CA fiber mat. In the in vitro study, indirect cytotoxic evaluation with human dermal fibroblasts (HDFa) showed that these materials released no substances in the levels that were harmful to the cells and the cells appeared to attach and proliferate well on these substrates. However, only the CA fiber mats containing AC/$HP{\beta}CD$ complexes at the $HP{\beta}CD$ to AC molar ratio of 0.5 was effective in upregulating the production of collagen of the cultured cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.49-56
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• 2000

The 2-O-$\alpha$-D-glucopyranosyl L-ascorbic acid (AA-2G) which was enzymatically glucosylated with the cyclodextrin glucanotransferase (CGTase) [EC 2.4.1.19] from Bacillus sp. JK-43 has been reported previously. The presnet experiments examined the optimal conditons for the productio of AA-2G from AA and soluble starch, and characterized the properties of the CGTase from Bacillus sp. JK-43. The reaction mixture for the maximal production of AA-2G was followings; 12% total substrate concentration, 1,400 usits/mL of CGTase and a mixing ratio of 2 : 3(g or AA : g of soluble starch). Under this condition, 1.76mM of AA-2G, which corresponded to 2.53% yield based on AA, was produced after incubation for 24hrs at 45$^{\circ}C$ (pH 5.5). The optimum pH and temperature for the CGTase activity were 6.0 and 45$^{\circ}C$, respectively. The enzyme was stable at pH 5.5 to 9.5, and at temperature up to 5$0^{\circ}C$. The thermostability of the enzyme could be enhanced up to 6$0^{\circ}C$ by the addition of 30mM CaCl2.

• KSBB Journal
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• v.17 no.1
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• pp.54-58
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• 2002

Curdlan gel containing various hydrophobic materials was prepared. The homogenized suspension of curdlan and hydrophobic materials was healed at $100^{\circ}C$. The curdlan gel can contain hydrophobic material up to 27%(v/v). When gel was compressed, only water in the gel was removed. When immersed in water, the dried gel absorbed water and became the original wet gel. The syneresis of gel decreased with the concentration of hydrophobic material added. DHA content of dried gel was about 90%. $\beta$-cyclodextrin inclusion complexes containing DHA were prepared with addition of water and ethanol. X-ray diffractograms of complexes showed a specific peak at 7-$8^{\circ}C$ and FT-IR spectrum of complex showed a specific C=O peak at $1745\textrm{cm}^{-1}$. Inclusion complex containing DHA was microcapsulated with curdlan and pullulan.

• YAKHAK HOEJI
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• v.37 no.4
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• pp.331-340
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• 1993

Inclusion complex of omeprazole(OMZ) with hydroxypropyl-$\beta$-cyclodextrin(HP-$\beta$-CD) was prepared by freeze-drying method. The complexation was confirmed by means of UV, CD, IR, DSC, XRD and $^{1}$H-NMR spectra. The benzimidazole moiety of OMZ might be found to be included into the cavity of HP-$\beta$-CD and the inclusion complex appeared to be $A_{L}$ type. The stoichiometric ratio of OMZ : HP-$\beta$-CD was found to be 1:1, and the stability constants of the inclusion complex by solubility and UV method were about 34 and 45 M$^{-1}$, respectively. The dissolution of OMZ was significantly enhanced from powder and. yablet of OMZ-HP-$\beta$-CD complex when compared to those of OMZ alone, and oil-to-water partition coefficient of OMZ-HP-$\beta$-CD complex was significantly higher than that of OMZ alone. Therefore, it was expected that the bioavailability of OMZ could be improved markedly by inclusion complexation of OMZ with HP-$\beta$-CD.

• Analytical Science and Technology
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• v.28 no.4
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• pp.255-259
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• 2015

A technique on the determination of Co(II) in aqueous samples with quinalizarin-β-cyclodextrin inclusion complex was developed. The conditions such as pH of the sample solution, the concentration of quinalizarin and the concentration of β-CD were optimized to 11.3(±0.2), 1.2×10⁻⁶ M and 8.0×10⁻⁶ M, respectively. Under these optimum conditions, the calibration curve of Co(II) was obtained over concentration range of 5.0×10⁻⁹ ~ 1.2×10⁻⁷ M. The detection limit was 4.2×10⁻⁹ M (0.25 ng/mL). For validating this proposed technique, aqueous samples(stream water, reservoir water and tap water) were used. Recovery yields of 95~105% were obtained. The relative standard deviation(%) in aqueous samples were less than 7.0%. Based on experimental results, it is proposed that this technique can be applied to the practical determination of Co(II).

• Food Engineering Progress
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• v.21 no.3
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• pp.215-224
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• 2017

Resveratrol was incorporated into various combinations of single- and double-layer nanoemulsions, prepared by self-assembly emulsification and complex coacervation with chitosan, alginate, and ${\beta}$-cyclodextrin, respectively. Resveratrol nanoemulsions were composed of medium-chain trigacylglycerols (MCTs), $Tween^{(R)}$ 80, water, chitosan, alginate, and ${\beta}$-cyclodextrin. The corresponding mixtures were formulated for the purpose of being used as a nutraceutical delivery system. Resveratrol nanoemulsions were obtained with particle sizes of 10-800 nm, with the size variation dependent on the emulsification parameters including the ratio of aqueous phase and surfactant ratio. Resveratrol nanoemulsions were characterized by evaluating particle size, zeta-potential value, stability, and release rate. There were no significant changes in particle size and zeta-potential value of resveratrol nanoemulsions during storage for 28 days at $25^{\circ}C$. The stability of resveratrol in the double-layer nanoemulsions complexed with chitosan or ${\beta}$-cyclodextrin was higher, compared with the single-layer nanoemulsions.

• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.461-466
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• 1986

A highly cyclodextrin glucanotransferase producing strain of Bacillus sp. was isolated from soil, and basic studies on the characteristics of the strain and its enzyme, conditions for the enzyme production, and the enzyme utilization were carried out. The isolated strain was aerobic, motile, endospore-forming and rod-shaped bacterium. Optimum pH and temperature for the enzyme action were 6.0 and 45$^{\circ}C$, and the enzyme was stable within 5$0^{\circ}C$, and between pH 6.0 and 10.0. The highest yield of the enzyme was obtained using the medium containing 2% corn starch as a carbon source, and 5% corn steep liquor, 0.1% urea and 0.25% ammonium sulfate as nitrogen sources. The fermentation conditions for the enzyme production in a jar fermentor were cetermined to be 3$0^{\circ}C$, 200rpm, 0.6vvm and 60hr cultural period. Stevioside transglycosylation catalyzed by this enzyme was identified by high performance liquid chromatography.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.148-153
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• 1989

A strain of alkalophilic Bacillus sp. YC-335 has been isolated from soil. The strain was capable of producing large amount of cyclodextrin glycosyl transferase (CGTase) in the culture broth. The preferable medium composition has been determined to be as follows : 1.5% soluble starch, 5% corn steep liquor, 0.1% $K_2$HPO$_4$, 0.02%mgSO$_4$.7$H_2O$, 1% CaCO$_3$and 1% Na$_2$CO$_3$(pH 10.3). The highest enzyme production was observed after 48 hours of cultivation at 31$^{\circ}C$. The optimum pH and temperature for the activity of crude enzyme were 6.0 and 5$0^{\circ}C$, respectively. The enzyme was stable between pH 5 and 9, and upto 5$0^{\circ}C$. The enzyme converted starch into $\alpha$-, $\beta$- and ${\gamma}$-CD in the relative amounts of 1:10:1.5, respectively.

• 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.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.802-804
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• 1990

A new colorimetric method to analyze ${\alpha}-Cyclodextrin({\alpha}-CD)$ by using a property of ${\alpha}-CD$ to decolor the starch-iodine complex, was presented. ${\alpha}-CD$ was quantitatively determined as follows. The ${\alpha}-CD$ standard solutions at concentrations up to 2 mg/ml were prepared. To 1ml of starch-iodine complex solution which contained starch(1%) and iodine (0.02% $I_2$, 0.2% KI) equivalently in distilled water, $200\;{\mu}l$ of ${\alpha}-CD$ standard solutions and 3 ml of distilled water were added and the absorbance was measured at 570 nm. Using this mothod ${\alpha}-CD$ concentration range at $0{\sim}2\;mg/ml$ could be determined and their absorbance patterns at 570 nm showed a good linearity. ${\beta}(CD)$ and glucose had no interference in this method for ${\alpha}-CD$ determination.