• Environmental Analysis Health and Toxicology
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• v.12 no.3_4
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• pp.75-84
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• 1997

Chromatographic retention behavior and separation of various phenol derivatives on a Partisil 10 ODS 3 column-with mobile phase containing $\alpha$-cyclodextrin-were systematically studied. The decrease in k' values caused by the addition of cyclodextrins in the mobile phase was based on the formation of an inclusion complex, resulting in weakening of the hydrophobic interaction between solutes and the stationary phase. The content of the organic solvent in the mobile phase also influenced k' values of the solutes, and k' values increased with a decrease of the content of organic solvent in the mobile phase. A simple equation has been derived that reveals the hyperbolic dependence of the capacity factor on the total concentration of cyclodextrin. A plot of the reciprocal of the capacity factor against (CD)$_T$ gives a straight line and the dissociation constant, K$_D$, of the inclusion complex can be calculated from the slope. The capacity factor decreased with increasing temperature. The enthalpy was calculated from the slope of van't Hoff plots. Under optimum conditions, some mixtures of phenol derivatives were able to separated successfully.

• YAKHAK HOEJI
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• v.47 no.4
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• pp.200-205
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• 2003

The stability constants for the inclusion complexes between carboxymethyl-$\beta$-cyclodextrin (CM-$\beta$-CD) and five $\beta$-blockers, such as atenolol (ATE), bisoprolol (BIS), metoprolol (MET), pindolol (PIN) and propranolol (PRO) were determined by capillary electrophoresis. The magnitude of stability was decreased as following order; PRO＞MET＞BIS＞ATE＞PIN. Among them PRO showed the highest affinity towards CM-$\beta$-CD with stability constants of 383 and 371 $M^{-l}$ for (R)- and (S)-enantiomer, respectively. PIN enantiomers showed the lowest stability towards CM-$\beta$-CD, while the selectivity between (R)- and (S)-enantiomer was higher than any other tested $\beta$-blocker.r.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.95-98
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• 2003

Enantioselectivity of the propranolol on β-cyclodextrin was simulated by molecular modeling. Monte Carlo (MC) docking and molecular dynamics (MD) simulations were applied to investigate the molecular mechanism of enantioselective difference of both enantiomeric complexes. An energetic analysis of MC docking simulations coupled to the MD simulations successfully explains the experimental elution order of propranolol enantiomers. Molecular dynamics simulations indicate that average energy difference between the enantiomeric complexes, frequently used as a measure of chiral recognition, depends on the length of the simulation time. We found that, only in case of much longer MD simulations, noticeable chiral separation was observed.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.145-148
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• 2009

Nucleotides are the building blocks of nucleic acids and essential for many cellular functions. In this study, ultrasonic absorption spectra of $\beta$-cyclodextrin ($\beta$-CD) and adenosine 5'-monophosphate (AMP) in aqueous solution were measured over the broad frequency range 0.1-40 MHz with emphasis on the low-frequency range below 1 MHz. Here we show that the interaction of $\beta$-CD and AMP complies with a typical spectrum of a single relaxation process. We determined reliable rate (kb) and equilibrium (K) constants and a standard volume change ($\Delta$V) of the reaction. They are $k_b=2.3{\times}{{10^{-6}}_s}^{-1},\;K=89M^{-1},\;and\;{\Delta}V=13.8(10^{-6}m^3mol^{-1})$, respectively.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.305-310
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• 1997

For the continuous production of transglucosylated steviosides, cyclodextrin glucanotransferase from Bacillus macerans was immobilized onto Diaion HPA 75 (styrene-divinylbenzene resin) that was screened from ion exchange resins, synthetic adsorbents and chitosan derivatives. The parameters influencing enzyme immobilization were examined in order to maximize the activity of immobilized enzyme. The optimum conditions for immobilization turned out to be: contact time 2 hr at 30$circ$C, pH 6$sim$9, and enzyme loading 20mg protein/g resin at 4.4 Os/Kg as osmolarity. Competing with other molecules having low molecular weight, enzyme was immobilized reversibly. The activity of immobilized enzyme was as high as 180U/g resin when the diafiltrated solution of stock enzyme was used. The optimum conditions for transglucosylation were as follows: pH 6.0, temperature 50$circ$C, 30% substrate solution composed of 15% stevioside mixture and 15% dextrin of which value of dextrose equivalent was about 9.0.

• Journal of Pharmaceutical Investigation
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• v.30 no.4
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• pp.267-271
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• 2000

The effect of cyclodextrins on the solubility and stability of aspalatone (acetylsalicylic acid maltol ester, AM, CAS 147249-33-0), which has been recently found to have an antithrombotic effect, was investigated. The addition of ${\beta}-cyclodextrin\;({\beta}-CD),\;dimethyl-{\beta}-cyclodextrin\;(DMCD)\;or\;2-hydroxypropyl-{\beta}-cyclodextrin\;(HPCD)$ to the aqueous solution increased the solubility of AM concentration-dependently. From the phase solubility diagram, stability constants for $AM-{\beta}-CD$, -DMCD or -HPCD complexes were calculated to be 43.1, 78.3 and $53.0\;M^{-1}$. The addition of ${\beta}-CD$, DMCD or HPCD to AM solution retarded the degradation rate of AM in the acidic region. However, ${\beta}-CD$ and HPCD rather acted as an accelerator of degradation in the neutral and alkaline regions. DMCD had a stabilizing effect at all pHs studied.

• Analytical Science and Technology
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• v.17 no.1
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• pp.16-22
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• 2004

Inclusion complexes of the p-nitrophenol with ${\beta}$-cyclodextrin (CD), sulfated ${\beta}$-CD, and ${\beta}$-CD polymer cross-linked with epichlorohydrine (EP) were prepared and characterized by Raman spectroscopy. The intensity of vibration peaks of the C-O and C-N at 1284 and $856cm^{-1}$ of the p-nitrophenol in the presence of EP-linked CD polymer was remarkably increased, respectively. The vibration modes at 1284 and $856cm^{-1}$ are assigned to the out-of phase C-C-O stretching mode and the C-N stretching mode, respectively. The vibration peaks at 1284 and $856cm^{-1}$ increased with increasing the content of EP-linked CD polymers, while decreased with increasing the p-nitrophenol content. Furthermore, the vibration mode of the $NO_2$ symmetric stretch at $1344cm^{-1}$ enhanced with increasing the content of p-nitrophenol.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.6-13
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• 2018

Well-modified amino-appended ${\beta}$-cyclodextrin ($AA-{\beta}-CD$) with an amino group at the primary face of the ${\beta}-CD$ was synthesized and used in the catalytic synthesis of chromeno pyrimido[1,2-b]indazol as supramolecular catalysts in water for the first time. $AA-{\beta}-CD$ was characterized by FT-IR, NMR, MALDI-TOF mass spectrometry, and SEM analysis. A possible reaction mechanism featuring molecular complexation was suggested based on 2D NMR (ROESY) spectroscopy, FE-SEM, DSC, and FT-IR. Advantages such as operational simplicity, recyclability of the catalysts, and accessibility in aqueous medium render this protocol eco-friendly.

• Archives of Pharmacal Research
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• v.6 no.1
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• pp.35-44
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• 1983

Interactions between thiamine.HCl and its disulfide derivatives TTFD. TPD and .alpha., .betha. cyclodextrins were investigated. By measuring the H-NMR, C-NMR chemical shifts, the assumption that cyclodextrin may from a inclusion complex with thiamines was supported qualitatively. To calculated the stability constants of them, anion exchange chromatography was applied. The simple, rapid HPLC method was proved to be pertinent thiamine/cyclodextrin system which was chemically unstable and less soluble.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.4
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• pp.337-345
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• 2011

In this report, we have investigated the functional properties change of phytochemicals by the encapsulation using water soluble host, ${\beta}$-cyclodextrin. The cream, shampoo, bodywash, and hair tonic containing phytochemical supramolecules were produced by mixing the surfactants, fragrances and the oriental herbal extracts encapsulated with ${\beta}$-cyclodextrin. Shampoo and bodywash including the encapsulated phytochemicals exhibited anti-growth activity against Gram (+) and Malassezia furfur which is known to cause dandruff. In cytotoxicity test against HDF (human dermal fibroblast), we could not detect any toxicity when the supramolecules content was less than 1 mg/mL. Our results suggest that the supramolecule of ${\beta}$-cyclodextrin with phytochemicals could be a safe anti-bacterial agent for cosmeceuticals.