• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.463-468
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• 2001

Cyclosophoraoses are a class of unbranced cyclic-(1longrightarrow2)-${\beta}$-D-glucans found in the Rhizobium species. Their unique cyclic structures and high solubility make them potent for inclusion complexation as a host for an insoluble guest molecule. A family of neutral cyclosophoraoses (DP 17-27) isolated from Rhizobium meliloti 2011 was used as a host for inclusion complexation with an insoluble guest drug, indomethacin. A high performance liquid chromatographic analysis indicated that the inclusion complexation of cyclosophoraoses greatly ehanced the solubility of indomethacin compared with ${\beta}$-cyclodextrin. The estimated value of the association constant of the complex in water for $\beta$-cyclodextrin and cyclosophoraoses was $523M^{-1} and 17,570M^{-1}$, respectively. NMR spectroscopy showed that the inclusion complex was characterized by the interaction of the indole ring moiety of indomethacin with the cavity of cyclosophoraoses.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.1-8
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• 1999

Most carbohydrates exist in nature in an insoluble state, which reduces their susceptibility towards various carbohydrases. Accordingly, they require intensive pretreatment for structural modification to enhance an enzyme reaction. The direct conversion of insoluble carbohydrates has distinct advantages for special types of reaction, especially exo-type carbohydrase; however, its application is limited due to structural constraints. This paper introduces two novel heterogeneous enzyme reaction systems for direct conversion of insoluble carbohydrates; one is an attrition coupled enzyme reaction system containing attrition-milling media for enhancing the enzyme reaction, and the other is a heterogeneous enzyme reaction system using extruded starch as an insoluble substrate. The direct conversion of typically insoluble carbohydrates, including cellulose, starch, and chitin with their corresponding carbohydrases, including cellulase, amylase, chitinase, and cyclodextrin glucanotransferase, was carried out using two proposed enzyme reaction systems. The conceptual features of the systems, their reaction characteristics and mechanism, and the industrial applications of the various carbohydrates are analyzed in this review.

• 한국응용과학기술학회지
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• 제32권3호
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• pp.451-460
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• 2015

An enantioselective recognition of D- and L-tryptophan (Trp)-b-cyclodextrin (CD) inclusion complex was performed using electrochemical and FT-Raman spectroscopic analysis. From the electrochemical analysis, the selectivity coefficient ($K_{DL}$) of b-CD inclusion complexes was found higher than that of the D- and L-Trp in phosphate buffered saline (PBS, pH=7.0) solution. The percentage of enantioselectivity ($I_{%{ee}}$) for peak current of D-Trp-b-CD inclusion complexes was observed higher than that of L-Trp-b-CD inclusion complexes in PBS solution. From Raman spectroscopy, chemical shift difference (D, $cm^{-1}$) for the C=C stretch, ring vibration, and ring breathing of D-Try-b-CD inclusion complex were observed higher than that of L-Trp-b-CD inclusion complex. The electrochemical and Raman spectroscopic analyses were found very useful for chiral detection of racemic amino acid in the presence of b-CD.

• Archives of Pharmacal Research
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• 제27권9호
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• pp.973-977
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• 2004

Carvedilol is administered as a racemic mixture of the R(＋)- and S(-)-enantiomers, although they exhibit different pharmacological effects. To investigate the stereoselective pharmacoki-netics, the enantiomeric separation of carvedilol in human plasma was undertaken using capil-lary electrophoresis (CE). Resolution of the enantiomers was achieved using 2-hydoxypropyl-$\beta$-cyclodextrin as the chiral selector. Phosphate buffer (50 mM, pH 4.0) containing 10 mM of 2-hydoxypropropyl-$\beta$-cyclodextrin was used as electrolytic buffer. Achiral separation was carried out with the same electrolytic buffer without chiral selector. Following a single oral administra-tion of 25-mg carvedilol to 11 healthy, male volunteers, stereoselective pharmacokinetic analy-sis was undertaken. The maximum plasma concentrations ( $C_{max}$) were 48.9 and 21.6 ng/mL for (R)-carvedilol and (S)-carvedilol, respectively, determined by the chiral method. The profiles of the plasma concentration of (RS)-carvedilol showed $C_{max}$ of 71.5, 72.2, and 73.5 ng/mL, as determined by the CE, HPLC/FD methods and calculations from the data of the chiral method, respectively.y.y.

• Advances in environmental research
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• 제1권2호
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• pp.97-108
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• 2012

Microbial degradation of hydrocarbons is found to be an attractive process for remediation of contaminated habitats. However the poor bioavailability of hydrocarbons results in low biodegradation rates. Cyclodextrins are known to increase the bioavailability of variety of hydrophobic compounds. In the present work we purified the Cyclodextrin Glucanotransferase (CGTase) enzyme which is responsible for converting starch into cyclodextrins and studied its role on biodegradation of diesel oil contaminated soil. Purification of CGTase from Enterobacter cloacae was done which resulted in 6 fold increase in enzyme activity. The enzyme showed maximum activity at pH 7, temperature $60^{\circ}C$ with a molecular weight of 66 kDa. Addition of purified CGTase to the treatment setup with Pseudomonas mendocina showed enhanced biodegradation of diesel oil ($57{\pm}1.37%$) which was similar to the treatment setup when added with Pseudomonas mendocina and Enterobacter cloacae ($52.7{\pm}6.51%$). The residual diesel oil found in treatment setup added with Pseudomonas mendocina at end of the study was found to be $73{\pm}0.21%$. Immobilization of Pseudomonas mendocina on alginate containing starch also led to enhanced biodegradation of hydrocarbons in diesel oil at 336 hours.

• BMB Reports
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• 제40권3호
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• pp.333-340
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• 2007

Gene encoding cyclodextrin glycosyltransferase (CGTase), from thermotolerant Paenibacillus sp. T16 isolated from hot spring area in northern Thailand, was cloned and expressed in E. coli (JM109). The nucleotide sequences of both wild type and transformed CGTases consisted of 2139 bp open reading frame, 713 deduced amino acids residues with difference of 4 amino acid residues. The recombinant cells required 24 h culture time and a neutral pH for culture medium to produce compatible amount of CGTase compared to 72 h culture time and pH 10 for wild type. The recombinant and wild-type CGTases were purified by starch adsorption and phenyl sepharose column chromatography and characterized in parallel. Both enzymes showed molecular weight of 77 kDa and similar optimum pHs and temperatures with recombinant enzyme showing broader range. There were some significant difference in pH, temperature stability and kinetic parameters. The presence of high starch concentration resulted in higher thermostability in recombinant enzyme than the wild type. The recombinant enzyme was more stable at higher temperature and lower pH, with lower $K_m$ for coupling reaction using cellobiose and cyclodextrins as substrates.

• Asian-Australasian Journal of Animal Sciences
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• 제18권6호
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• pp.835-840
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• 2005

The main objective of the present study was to determine the effect of dietary $\beta$-cyclodextrin ($\beta$-CD) on egg laying performance and cholesterol content of egg yolk. Feed intake, egg production and egg weight varied slightly, but not significantly, between hens fed either a control diet or a diet containing one of an increasing series of $\beta$-CD concentrations (2%, 4% or 6%). However, feed intake, egg production and egg weight were all lower in the hens fed on 8% $\beta$-CD (p<0.05). No difference in haugh unit values, egg yolk color and egg shell thickness were found between the different treatments. The cholesterol content of egg yolks (mg/g yolk) was significantly decreased by 0.71, 2.98, 4.00 and 4.24 mg in eggs from hens maintained on 2%, 4%, 6% and 8% $\beta$-CD, respectively (p<0.05). These observations indicate that appropriate supplementation of diets with $\beta$-CD can reduce the cholesterol content of eggyolks, thus raising the prospect of the production of a healthier functional food.

• 한국음향학회지
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• 제31권2호
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• pp.100-106
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• 2012

The aim of this work was to reveal the effect of butanoic acid in its dissociated form and undissociated form as a guest molecule on the kinetic parameters in an inclusion reaction with ${\beta}$-cyclodextrin (${\beta}$-CD). Ultrasonic absorption measurements in the frequency range from 0.2 to 45 MHz were carried out for ${\beta}$-CD solutions with butanoic acid at $25^{\circ}C$ by ultrasonic relaxation method. The rate and the equilibrium constants were obtained from the guest concentration dependence of the relaxation frequency, and the standard volume change of the complexation reaction were obtained from the maximum absorption per wavelength. A single relaxational absorption was observed, and the cause of the relaxation was attributed to a perturbation of the chemical equilibrium associated with a complexation reaction between ${\beta}$-CD and butanoic acid. These results were compared with those in solutions containing both ${\beta}$-CD and different guest molecules. It was found that the hydrophobicity of guest molecules played an important role in the formation of the inclusion complex and also that the charge on the carboxylic group had a considerable effect on the kinetic characteristics of the complexation reaction.

• 약학회지
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• 제38권4호
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• pp.372-378
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• 1994

Choleretic effect and absorption of ursodeoxycholic acid (UDCA) in rats were studied using UDCA alone and it's ${\beta}-cyclodextrin$ $({\beta}-CyD)$ inclusin complex (UDCA-IC). In spite of increase in solubility and dissolution rate, absorption of UDCA-IC was decreased compared with UDCA alone. Choleretic effect of UDCA-IC was also decreased. It looks that UDCA forms stronger inclusion complex with ${\beta}-CyD$ than any other drug or organic biological material. From this study, it was suggested that UDCA might be used as a new potential competing agent when inclusion complexes of drugs with ${\beta}-CyD$ were administered for the improvement of poor bioavailability.

• 약학회지
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• 제38권3호
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• pp.300-310
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• 1994

Physicochemical properties for the inclusion complex of chenodeoxycholic acid(CDCA) and it's $7{\beta}-hydroxy$ epimer ursodeoxycholic acid(UDCA) with ${\beta}-cyclodextrin({\beta}-CyD)$ were studied. The formation of the complex in the solid state were confimed by polarized microscopy and differential scanning calorimetry(DSC). Proton nuclear magnetic resonance$(^1H-NMR)$spectroscopy showed that CDCA and UDCA form an inclusion complex with ${\beta}-CyD$ in aqueous solution. The 1 : 1 stoichiometry of the complex was dextermined by the continuous variation method. From DSC and $^1H-NMR$ studies, there were not any differences between CDCA and UDCA. Complex of CDCA and UDCA showed increase in solubility and dissolution compared with CDCA and UDCA alone, respectively. Solubility pattern of UDCA complex was pH independent but, CDCA complex was like that of CDCA. Dissolution rate increased markedly in case of UDCA complex compared with CDCA complex, especially in acidic pH value.