• Title/Summary/Keyword: ${\beta}$-Cyclodextrin

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Permeation and Enzymatic Degradation of Aspalatone in Gastrointestinal Tract of Rabbit (아스팔라톤의 토끼 위장관 점막 투과 및 효소적 분해)

  • Chun, In-Koo;Gwak, Hye-Sun
    • Journal of Pharmaceutical Investigation
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    • v.31 no.1
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    • pp.27-35
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    • 2001
  • To evaluate the site-specific permeation of aspalatone (acetylsalicylic acid maltol ester, AM) through gastrointestinal tract, the enzymatic degradation and permeation studies were carried out using gastric, duodenal and jejunal mucosae of rabbits. It was found that $15.2{\pm}11.4%$, $11.6{\pm}5.2$ and $0.8{\pm}0.6%$ of the donor dose of AM, salicylmaltol (SM) and aspirin (ASA) permeated through the upper gastric mucosa after 8 hr of permeation, respectively. After 8 hr of AM permeation, SM and ASA were measured to be $15.0{\pm}1.7$ and $2.6{\pm}0.8%$ of the dose in the donor solutions, respectively, and salicylic acid (SA) was not detected even after 6 hr, suggesting a very low gastric damage. For the gastric mucosa, the increase of donor dose from 100 to $1,000\;{\mu}g/ml$ increased the permeation flux dose-dependently (r=0.9905). For the duodenal and jejunal mucosae, however, AM was fully degraded into SM and SA due to the esterase activities within 30 min. AM and ASA were not detected in the receptor solution. This result indicates that AM is not a prodrug of ASA. Addition of potassium fluoride (0.5%) into the donor solution delayed the degradation of AM, but did not allow the permeation through duodenal mucosa even by the inhibition of esterase activity. The addition of $dimethyl-{\beta}-cyclodextrin$ and $2-hydroxypropyl-{\beta}-cyclodextrin$ (5%) into the donor solutions also did not show favorable effects on the permeation of AM through various mucosae. In comparison of permeation rates of AM and ASA through the upper gastric mucosa, the flux of ASA was 4.2 times faster than AM based on the molar concentration. ASA also was fully degraded in the donor solutions faced with duodenal and jejunal mucosae within 2 hr, and was not detected in the receptor solution, suggesting a slower metabolism compared with AM.

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Analysis of Sorption and Desorption Behaviors of Radionuclides (Cobalt and Strontium) in Natural Soil (자연 토양에서의 방사성 핵종(Co, Sr)의 흡/탈착 거동 특성 평가)

  • Cheon Kyeong-Ho;Shin Won Sik;Choi Jeong-Hak;Choi Sang June
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.06a
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    • pp.485-495
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    • 2005
  • This study was conducted to investigate sorption and desorption behaviors of radionuclides (Cobalt and Strontium) in natural soil. Sorption kinetics and isotherms were analyzed to predict sorption behaviors of radionuclides in natural soil and the experimental data were fitted to several sorption models. Desorption experiments were also performed with or without CMCD at constant pH and ion strength conditions. The results showed that $Sr^{2+}$ was more strongly sorbed than $Co^{2+}$ in natural soil. Both $Co^{2+}$ and $Sr^{2+}$ followed a pseudo-second order kinetics and Sips model. The desorption-resistance of $Co^{2+}$ and $Sr^{2+}$ was estimated using a natural surfactant Carboxymethyl-${\beta}$-cyclodextrin(CMCD) or non-desorbing fraction. Desorption of radionuclides was partially irreversible and $Sr^{2+}$ was more resistant than $Co^{2+}$ Addition of CMCD facilitated desorption of $Co^{2+}$ and $Sr^{2+}$ from soil.

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EFFECTS OF SURFACTANTS ON THE FENTON DEGRADATION OF PHENANTHRENE IN CONTAMINATED SEDIMENTS

  • Jee, Sang-Hyun;Ko, Seok-Oh;Jang, Hae-Nam
    • Environmental Engineering Research
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    • v.10 no.3
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    • pp.138-143
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    • 2005
  • Laboratory batch experiments were conducted to evaluate the Fenton degradation rates of phenanthrene. Fenton reactions for the degradation of phenanthrene were carried out with aqueous and slurry phase, to investigate the effects of sorption of phenanthrene onto solid phase. Various types of surfactants and electrolyte solutions were used to evaluate the effects on the phenanthrene degradation rates by Fenton's reaction. A maximum 90% removal of phenanthrene was achieved in aqueous phase with 0.9% of $H_2O_2$ and 300 mg/L of $Fe^{2+}$ at pH 3. In aqueous phase reaction, inhibitory effects of synthetic surfactants on the removal of phenanthrene were observed, implying that surfactant molecules acted as strong scavenger of hydroxyl radicals. However, use of $carboxymethyl-{\beta}-cyclodextrin$ (CMCD), natural surfactant, showed a slight enhancement in the degradation of phenanthrene. It was considered that reactive radicals formed at ternary complex were located in close proximity to phenanthrene partitioned into CMCD cavities. It was also show that Fenton degradation of phenanthrene were greatly enhanced by addition of NaCl, indicating that potent radical ion ($OCI^-$) played an important role in the phenanthrene degradation, although chloride ion might be acted as scavenger of radicals at low concentrations. Phenanthrene in slurry phase was resistant to Fenton degradation. It might be due to the fact that free radicals were mostly reacting with dissolved species rather than with sorbed phenanthrene. Even though synthetic surfactants were added to increase the phenanthrene concentration in dissolved phase, low degradation efficiency was obtained because of the scavenging of radicals by surfactants molecules. However, use of CMCD in slurry phase, showed a slight enhancement in the phenanthrene degradation. As an alternative, use of Fenton reaction with CMCD could be considered to increase the degradation rates of phenanthrene desorbed from solid phase.

Browning and Pungent Taste Reduction Techniques in Onion Extract (양파추출물의 갈변 및 매운맛 억제기술)

  • Kim, Hee Sun;Kim, Myung Hwan
    • Food Engineering Progress
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    • v.13 no.4
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    • pp.360-364
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    • 2009
  • The onion extractions of MIX treatment (5% $\beta$ cyclodextrin+1% calcium chloride+1% soluble starch mixture solution) using hot water (100${^{\circ}C}$ and 80${^{\circ}C}$) and ultrasonic treatment (25${^{\circ}C}$) incresed L values and decreased a and b values apart from the extraction methods. Extent of the browning reaction as caused by the MIX treatment (0.093) following 100${^{\circ}C}$ water extraction resulted in as low as 31% O.D. level, as compared to the control(0.296). Analysis of the pyruvic acid showed that the control had higher content of pyruric acid than MIX-treated samples. The MIX treatment had lower intensities and higher preferences of browning color and pungency taste compared to the control. The total and coliform microbial counts increased continuously during storage period, while the MIX treatment reduced the number of viable cells. Finally, it was concluded that the MIX treatment was highly effective in suppressing the undesirable browning color and pungent taste after processing, and the microbes increment during storage.

Cyclodextrin Glucanotransferase와 Cyclodextrinase를 생산하는 Bacillus 속 세균의 분리와 그 효소들의 특성

  • Kwon, Hyun-Ju;Nam, Soo-Wan;Kim, Kwang-Hyun;Kwak, Young-Gyu;Kim, Byung-Woo
    • Microbiology and Biotechnology Letters
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    • v.24 no.3
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    • pp.274-281
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    • 1996
  • A bacterium producing Cyclodextrin Glucanotransferase (CGTase) and Cyclodextrinase (CDase) was isolated from soil, and named as Bacillus stearothermophilus KJ16. The growth of the isolated strain occurred in two steps, and syntheses of CGTase and CDase were dependedt on the growth cycle of the cell. CGTase was constitutively synthesized during the 1st growing phase, while CDase was synthesized inducibly during the 2nd growing phase. When the midium pH was controlled at 7.0 the maximum enzyme activities of CGTase and CDase were increased by 12-fold (1300 mU/ml) and 2-fold (225 mU/ml), respectively, compared with the pH-uncontrolled batch culture. The CGTase of the isolate converted soluble starch to CDs with the ratio of $\alpha$-CD:$\beta$-CD:$\gamma$-CD=42:46:12 at $55^{\circ}C$.The optimal pH and temperature of CGTase were 6.0 and $60^{\circ}C$, respectively and the optimal pH and temperature of CDase were 6.0 and $55^{\circ}C$. The molecular weights of the purified CGTase and CDase were estimated to be 65, 000 and 68, 000 dalton, respectively. Among several substrates, $\gamma$-CD was most rapidly hydrolyzed by the purified CDase.

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Effects of Anti-inflammation and Skin Barrier by Genistein Cyclodextrin Complex (제니스테인 Cyclodextrin 포접체의 항염 및 피부장벽에 미치는 영향)

  • Choi, Dong Jun;Cho, Uk Min;Choi, Da Hee;Hwang, Hyung Seo
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.44 no.2
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    • pp.171-181
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    • 2018
  • Genistein is one of the representative isoflavone compounds isolated from soybeans and has been studied very well for its anti-aging and anti-inflammatory activity through previous studies. However, although genistein exhibits high solubility in organic solvents, it shows low bioavaility due to the low water solubility. In this study, we compared directly the functional difference between genistein and genistein cyclodextrin complex which has the improved water solubility and stability by cell based assay. Cell cytotoxicity experiment were carried out on RAW264.7 with CCK-8 assay and cytotoxicity was appeared from $10{\mu}g/mL$, thereby maximum concentration was set to $10{\mu}g/mL$ in all condition. We discovered that genistein CD complex suppressed NO production and iNOS expression as concentration dependent manner in the condition of LPS rather than genistein. Also, we could understand that genistein CD complex was able to down-regulate mRNA expression of anti-inflammatory cytokines such as $IL1-{\alpha}$, $IL1-{\beta}$, IL-6, and $TNF-{\alpha}$ as concentration dependent manner in the presence of LPS. In addition, we verified that genistein CD complex increased TEER of HaCaT human keratinocyte cells as concentration dependent pattern and stimulated cell division and migration rather than genistein in cell migration assay. Thus, it is expected that it can be used as an effective cosmetic raw material for improving atopic dermatitis or skin barrier if clinical studies on skin regeneration and skin barrier of the genistein CD complex are carried out.

Increased Production of Digitoxin from Digitoxin by Biotransformation Using Plant Cell Culture

  • Hong, Hee-Jeon;Lee, Jong-Eun;Kim, Dong-Il
    • Proceedings of the Botanical Society of Korea Conference
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    • 1995.06a
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    • pp.79-90
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    • 1995
  • Production of a cardiac glycoside, digoxin, by 12$\beta$-hydroxylation from digitoxin was studied in plant cell suspension cultures of Digitalis lanata. In order to increase the conversion yield, various culture conditions including immobilization were investigated and optimized. Since digoxin was released in the medium temporarily and converted further into a glucosylated product, deacetyllanatoside C, in situ adsorption of digoxin was employed to recover the product continuously. Amberlite resin XAD-8 showed the best adsorption characteristics for digoxin among the examined resins, and an integrated process was developed to increase the productivity. In addition, it was found that the utilization of $\beta$-cyclodextrin to entrap digoxin during the culture enhanced the biotransformation yield significantly.

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The Study on New Radiating Structure with Multi-Layered Two-Dimensional Metallic Disk Array for Shaping flat-Topped Element Pattern (구형 빔 패턴 형성을 위한 다층 이차원 원형 도체 배열을 갖는 새로운 방사 구조에 대한 연구)

  • 엄순영;스코벨레프;전순익;최재익;박한규
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.13 no.7
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    • pp.667-678
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    • 2002
  • In this paper, a new radiating structure with a multi-layered two-dimensional metallic disk array was proposed for shaping the flat-topped element pattern. It is an infinite periodic planar array structure with metallic disks finitely stacked above the radiating circular waveguide apertures. The theoretical analysis was in detail performed using rigid full-wave analysis, and was based on modal representations for the fields in the partial regions of the array structure and for the currents on the metallic disks. The final system of linear algebraic equations was derived using the orthogonal property of vector wave functions, mode-matching method, boundary conditions and Galerkin's method, and also their unknown modal coefficients needed for calculation of the array characteristics were determined by Gauss elimination method. The application of the algorithm was demonstrated in an array design for shaping the flat-topped element patterns of $\pm$20$^{\circ}$ beam width in Ka-band. The optimal design parameters normalized by a wavelength for general applications are presented, which are obtained through optimization process on the basis of simulation and design experience. A Ka-band experimental breadboard with symmetric nineteen elements was fabricated to compare simulation results with experimental results. The metallic disks array structure stacked above the radiating circular waveguide apertures was realized using ion-beam deposition method on thin polymer films. It was shown that the calculated and measured element patterns of the breadboard were in very close agreement within the beam scanning range. The result analysis for side lobe and grating lobe was done, and also a blindness phenomenon was discussed, which may cause by multi-layered metallic disk structure at the broadside. Input VSWR of the breadboard was less than 1.14, and its gains measured at 29.0 GHz. 29.5 GHz and 30 GHz were 10.2 dB, 10.0 dB and 10.7 dB, respectively. The experimental and simulation results showed that the proposed multi-layered metallic disk array structure could shape the efficient flat-topped element pattern.

Studies on Dissolution of Fentiazac from ${\beta}-Cyclodextrin$ Inclusion Complex (${\beta}$-씨클로덱스트린 포접화합물로부터 펜티아작의 용출)

  • Yoon, Hyung-Joong;Back, Un-Bong;Seo, Seong-Hoon;Kim, Soo-Uck
    • Journal of Pharmaceutical Investigation
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    • v.20 no.3
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    • pp.153-159
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    • 1990
  • To increase the solubility of fentiazac which is used widely as a non-steroidal antiinflammatory drug, its inclusion complex and suppositories were prepared and studied. Inclusion complexes of fentiazac with ${\beta}-cyclodertin$ $({\beta}-CyD)$ were prepared by four diffrent methods; coprecipitation method, kneading method, solvent evaporation method, freeze drying method. Suppositories of $fentiazac/{\beta}-CyD$ with PEG 1500 and Witepsol H-15 were prepared by solvent evaporation method and freeze drying method. Inclusion complex formation of fentiazac with ${\beta}-CyD$ was ascertained by powder X-ray diffractometry, differential scanning calorimetry and IR spectroscopy. The dissolution rate of fentiazac from the inclusion complex increased in distilled water and KP 2nd disintegration test fluids (pH 6.8) but extemly decreased in KP 1st disintegration test fluid (pH 1.2). Inclusion complexes prepared by freeze drying method and solvent evaporation method were similar. Freeze drying method seemed to be suitable for preparation of complex with most higher dissolution rate but coprecipitation method seemed not to be suitable. The dissolution rate of fentiazac increased markedly by ${\beta}-CyD$ complexation. The release rates of suppositories increased in the following order. Complex prepared by freeze dying method in PEG 1500 > complex prepared by solvent evaporation method in PEG 1500 > fentiazac in PEG 1500 > complex prepared by freeze dying method in Witepsol H-15 > complex prepared by solvent evaporation method in Witepsol H-15 > fentiazac in Witepsol H-15.

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Determination of inclusion complex formation constants for the β-CD and [Cu(Dien)(sub-Py)]2+ ion by the spectrophotometric methods (분광 광도법에 의한 β-CD와 [Cu(Dien)(sub-Py)]2+이온간의 복합체 형성 상수 결정)

  • Kim, Chang Suk;Oh, Ju Young
    • Analytical Science and Technology
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    • v.20 no.5
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    • pp.406-412
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    • 2007
  • The formation of inclusion complexes between ${\beta}$-cyclodextrin and diethylenetriamine substituted-pyridine copper(II) perchlorate; [Cu(dien)(sub-py)] $(ClO_4)_2$, were studied by spectrophotometric methods. On account of charge-transfer band(MLCT) and $^2T_2{\rightarrow}^2E$, the two high peaks were observed as an inclusion complex for the [${\beta}$-CD]$[Cu(dien)(p-Cl-py)]^{2+}$ in the ultraviolet region of the spectrum. The ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion formed a 1:1 complex, and the formation constants were decreased with the increasing temperatures, due to weak binding energy between ${\beta}$-CD and $[Cu(dien)(sub-py)]^{2+}$ ion. This reaction was controlled by enthalpy. In a correlation of the Hammett substituent constants and formation constants for the reaction, formation constants were increased by strong binding energy in the inclusion complexes when electron donating groups were substituted in pyridine ring.