• 한국미생물·생명공학회지
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• 제20권1호
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• pp.73-78
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• 1992

Tryptophanase를 이용하여 트립토판 합성시 인돌의 효소활성 저해를 억제하기 위하여 유가식 조업, 유기용매 이상계의 사용, 그리고 cyclodextrin의 첨가등에 대하여 연구하였다. 효소 농도가 0.5mg/ml일때 인돌 농도 0.4mM 부근에서 트립토판 생성이 가장 빨랐으며 그 이상에서는 효소활성이 심한 저해를 받았다. 초기 인돌 농도가 20mM일 때는 27시간 반응후 인돌의 전환율이 20인데 비하여 반응기내 인돌 농도를 5mM 이하로 유가식 조업을 하였을 때 전환율이 80%로 향상되었다.

• Journal of Pharmaceutical Investigation
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• 제27권1호
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• pp.29-38
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• 1997

Precipitation was formed during the preparation of decoction from a mixture of Scutellariae Radix and Coptidis Rhizoma. Baicalin and berberine were identified in this coprecipitated product (CPP) and these components were the active ingredients of two herbal medicine. We extracted respectively crude baicalin and berberine in Scutellariae Radix and Coptidis Rhizoma and prepared coprecipitate of crude baicalin-berberine. To increase the stability and bioavailability of coprecipitate of crude baicalin-berberine(CBB), which is slightly soluble drug, its inclusion complex was prepared and studied in this experiment. Inclusion complex of CBB with ${\beta}-cyclodextrin(CBB-{\beta}-CD)$ was prepared by freeze drying method and its characteristics were ascertained by means of solubility test, differential thermal analysis(DTA) and scanning electron microscope(SEM). The type of $CBB-{\beta}-CD$ is classified as $A_L-type$ on phase solubility diagram, and the stoichiometric ratio of CBB(baicalin in CBB) : ${\beta}-CD$ complex is 1:1 and formation constant is 151 $M^-1$. The solubility, dissolution, in situ absorption and serum concentration of $CBB-{\beta}-CD$ were significantly increased when compared to CBB. Therefore enhanced bioavailability of CBB by inclusion complexation with ${\beta}-cyclodextrin$ might be useful for dosage form design of active ingredients of two herbal medicine.

• 한국식품과학회지
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• 제41권5호
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• pp.509-514
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• 2009

생선 등에서 비린내 성분중 하나인 트리메틸아민을 이취 유발 물질로 하여 6% 쌀뜨물을 기준으로 아밀로오스, 전분, ${\alpha}$-cyclodextrin 등과 이취 제거효과를 전자코를 이용하여 비교 분석해보았다. 쌀뜨물과 이취물질의 반응시간이 길수록 그만큼 결합이 많이 이루어져 이취 저감화 효과가 크게 나타났으며 쌀뜨물의 농도가 높을수록 반응할 수 있는 전분의 양이 많아 그만큼 이취가 적게 나타나는 것을 알 수 있었다. 또한 쌀뜨물이 아닌 다른 탄수화물 용액과의 반응에서 6% 쌀뜨물과 전분의 효과는 비슷하였으며 ${\alpha}$-cyclodextrin은 농도가 10배 정도 낮음에도 불구하고 비슷한 경향을 보여 그만큼 이취 저감화 효과가 큰 것을 알 수 있었다. 반면 밀가루는 단백질의 함량이 높아 다른 물질들에 비해 결합정도가 낮을 거라 예상되며 쌀뜨물의 이취 저감화 효과는 아밀로오스뿐 아니라 아밀로펙틴의 영향도 받는 다는 것을 간접적으로 예상되는 바이다. 이러한 결과들을 통해 향후 신제품 개발이나 품질 관리에 활용될 수 있을 것이며 이러한 이취 제거 성분들은 전통식품 같이 첨가물이나 가공품을 많이 첨가하기가 어려운 시료에서의 활용이 높을 것으로 기대되는 바이다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제3권2호
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• pp.103-108
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• 1998

A hydrophobic substrate triolein was hydrolyzed by lipase in a mono-phase reaction system containing cyclodextrin(CD) as emulsifier. The triolein was transformation to an emulsion-like state in the CD containing reaction system in contrast to the oil-droplet like state without CD due to the formation of an inclusion complex between the lipids and CDs. The hydyrolysis reaction increased substantially in the CD containing reaction system, and the optimum reaction conditions including the amount of lipase, ${\beta}$-CD concentration, and mixing ratio of triolein and ${\beta}$-CD, were determined. The performance of the enzyme reaction in a mono-phase reaction system was compared with that of a two-phase reaction system which used water immiscible hexane as the organic solvent. The role of a CD in the mono-phase reaction system was elucidated by comparing the degree of the inclusion complex formation with triolein and oleic acid, Km and Vmax values, and product inhibition by oleic aicd in aqueous and CD containing reaction systems. The resulting enhanced reaction seems to be caused by two phenomena; the increased accessibility of lipase to triolein and reduced product inhibition by oleic acid through the formation of an inclusion complex.

• Bulletin of the Korean Chemical Society
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• 제35권8호
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• pp.2487-2493
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• 2014

Dimeric ${\beta}$-cyclodextrin linked by a thioether bridge was synthesized from a reaction of mono-6-iodo-6-deoxy-${\beta}$-cyclodextrin with sodium sulfide, and the structure was analyzed using nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The effects of thioether-bridged dimeric ${\beta}$-CD on the aqueous solubility of flavonols (myricetin, quercetin, and kaempferol) were investigated by ultraviolet-visible spectroscopy. The aqueous solubility of myricetin, quercetin, and kaempferol were enhanced 33.6-, 12.4-, and 10.5-fold following the addition of 9 mM of thioether-bridged dimeric ${\beta}$-CD. In comparison, the aqueous solubility of myricetin, quercetin, and kaempferol were enhanced 5.4-, 3.3-, and 2.7-fold using the same concentration of monomeric ${\beta}$-cyclodextrin. Furthermore, the formation of flavonol/thioether-bridged dimeric ${\beta}$-CD inclusion complexes was confirmed with nuclear magnetic resonance, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The results showed that the nature of the complexes significantly differed from that of free flavonols. Herein, we suggest that the thioether-bridged dimeric ${\beta}$-CD can act as an effective complexing agent for flavonols.

• 약학회지
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• 제37권3호
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• pp.216-227
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• 1993

Complex formations of practically insoluble antelmintic drugs such as mebendazole (MBZ), albendazole (ABZ) and flubendazole (FBZ) with dimethyl-$\beta$-cyclodextrin (DM-$\beta$-CyD) and 2-hydroxypropyl-$\beta$-cyclodextrin (HP-$\beta$-CyD) together with $\alpha$-, $\beta$- and $\gamma$-cyclodextrins(CyDs) in duffered solutions were investigated by solubility method. $A_{L}$ type phase solubility diagrams were obtained in all cases except for the complexation (B$_{s}$, type) of FBZ with $\gamma$-CyD. The highest stability constants were obtained with DM-$\beta$-CyD, followed by $\alpha$-CyD > $\beta$-CyD > HP-$\beta$-CyD > $\gamma$-CyD for ABZ, and HP-$\beta$-CyD > $\gamma$-CyD > $\beta$-CyD > $\alpha$-CyD for FBZ at pH 1.2. On the other hand, solid dispersion systems of ABZ and FBZ with $\beta$- and DM-$\beta$-CyDs were prepared by solvent evaporation method and evaluated by dissolution, differential thermal analysis and powder x-ray diffractometry. The dissolution rates of ABZ- and FBZ-DM-$\beta$-CyD solid dispersions were much faster than those of drugs alone, corresponding physical mixtures and tablets on market both at pH 1.2 and 6.8. Although dissolution rates of all samples at pH 6.8 were by far lower than those obtained at pH 1.2, as explained by pH-solubility profiles for ABZ and FBZ, the dissolution rates at pH 6.8 of ABZ from $\beta$- and DM-$\beta$-CyD solid dispersions exceeded the respective equilibrium solubility (23.9 $\mu\textrm{g}$/ml). Fast dissolution of ABZ from solid dispersions with CyDs was attributed to the reduction of drug crystallinity and particle size which was supported by DTA and powder x-ray diffractometry. Consequently these results suggest that solid dispersion systems with CyDs may provide useful means to markedly enhance the solubility and dissolution of benzimidazole antelmintic drugs.

• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.584-589
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• 2005

This study was carried out to investigate the effects of different types of $\beta$-cyclodextrin ($\beta$-CD) treatments on chemical and sensory characteristics of cholesterol-reduced cream cheese. The cholesterol removal rates were 92.0% in cream cheese treated by powder $\beta$-CD, and 82.6% in cream cheese treated by crosslinked $\beta$-CD. Amounts of short-chain fatty acid and free amino acids were significantly lower in cream cheese made by crosslinked $\beta$-CD-treated milk, especially after 2 weeks storage, compared with those of no $\beta$-CD-treated control and cream cheese made by powder $\beta$-CD treated milk. Among rheological properties, cohesiveness was significantly higher, and gumminess in cream cheese made by crosslinked $\beta$-CD-treated milk was slightly lower than others. In sensory analysis, no difference was found in texture among treatments, while bitterness was lower in the early stage of storage, and overall quality was higher score, in cream cheese made by crosslinked $\beta$-CD-treated cream at 3 and 4 week storage, compared with those in control and powder $\beta$-CD-treated group. The present study indicated that crosslinked $\beta$-CD treatment resulted in an efficient cholesterol removal rate over 80% and a deceleration of ripening, which may provide a longer shelf life without significant adverse effects in chemical and sensory properties.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권3호
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• pp.174-180
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• 2000

Cyclodextrin glucanotransferase (CGTasa) from Thermoanaerobacter sp. was adsorbed on the ion exchange resin Amberlite IRA-900. The optimum conditions for the immobilization of the CGTase were pH6.0 and 600 U CGTase/g resin, and the maximum yield of immobilization was around 63% on the basis of amount ratio of the adsorbed enzyme to intial amount in the solution. Immobilixation of CGTase shifted the optimum temperature for the enzyme to peoduce transglycosylated xylitol from 7$0^{\circ}C$ to 9$0^{\circ}C$ and improved the thermal stability of immobilized CGTase, especially after the addition of soluble starch and calcium ions. Transglycosylated xylitol was continuoncly produced using immobilized CGTase in the column type packed bed reactor, and the operating conditions for maximum yield were 10%(w/v) dextrin (13 of the dextrose equivalent) as the glycosyl donor, 10%(w/v) dextrin (13 of the dextrose equivalent) as the glycosyl donor, 10%(w/v) xylitor as the glycosyl acceptor, 20mL/h of medium fiow rate, and 6$0^{\circ}C$. The maximum yield of transglycosylated xylitol and productivity were 25% and 7.82 g.L-1.h-1, respectively. The half-life of the immobilized CGTase in a column type packed bed reactor was longer than 30 days.

• Journal of Pharmaceutical Investigation
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• 제25권3호
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• pp.205-211
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• 1995

To increase the solubility of iodine and iodine releasing agents, which are used widely as a topical broad spectrum antiseptics and disinfectant sanitizers, its inclusion complexes were prepared and studied. Inclusion complexes of iodine with ${\beta}-cyclodextrin$ were prepared by coprecipitation method and complex formation was acertained by differential scanning calorimetry and microscopic observation. Iodine content of inclusion complex was determined by means of iodometry. Tablets containing inclusion complex were manufactured with sugar, citric acid, magnesium stearate, dextrose. Stability of inclusion complexes and tablets was evaluated by accelerated stability test, and comparing with PVP-iodine. During preparation, use of 50% ethanol solution is preferable to water as the medium because the former resulted in more stable complex for a month under accelerated storage conditions. Solubility of iodine in KI aqueous solution was 0.048 g/ml and lower than in 50% ethanol solution. Inclusion complex and its tablets were very stable at severe condition for one month, and comparable to PVP-iodine in the aspect of stability. Inclusion complex tabletswere not affected with citric acid, sugar, dextrose, and direct tableting method was recommendable because wet granulation using ethanol gave some release of included iodine during process.

• 한국식품저장유통학회지
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• 제9권2호
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• pp.189-193
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• 2002

천연식초를 이용하여 분말식초의 제조방법을 개발하고자 부형제의 비율을 달리하여 제조한 분말식초의 품질특성을 평가하여 분말식초의 제조 가능성을 검토하였다. 혼합 피복 물질로 제조된 분말식초의 품질특성을 비교한 결과 $\beta$-cyclodextrin과 gum arabic이 2.5:7.5의 비율로 제조한 분말식초가 비교적 낮은 수분함량을 나타내었고 산도는 높은 수치를 나타내 식초를 포집하는 능력이 가장 좋은 것으로 나타났다. 또한 이 비율로 제조한 분말식초의 흡습성 또한 비교적 낮은 값을 나타내었으며 열안정성은 모든 시료가 높은 수치를 나타내 열에는 모두 안정함을 알 수 있었다. 주사 현미경으로 관찰한 분체의 형태는 모두 구형을 형성하여 분말식초에서 캡슐이 형성되었음을 알 수 있었다. 관능검사 결과도 신맛의 증가로 높은 점수를 받았다. 이상의 결과로 분말식초의 제조시 피복물질의 혼합비율별은 $\beta$-cyclodextrin 과 gum arabic을 2.5:7.5의 비율로 제조하는 것이 가장 우수한 것으로 나타났다.