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

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Desorption Characteristics of Cobalt, Strontium, and Cesium in Natural Soil and Kaolin Using CMCD (CMCD를 이용한 자연토양 및 카올린에서의 코발트, 스트론튬, 세슘의 탈착 특성)

  • Choi, Jeonghak;Cheon, Kyeongho
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.12
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    • pp.61-69
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    • 2014
  • Carboxymethyl-${\beta}$-cyclodextrin (${\beta}$-CMCD), as a biodegradable surfactant with hydrophobic and hydrophilic properties, has potential advantages of being applicable to the simultaneous treatment of multiple contaminated soils. In this study, the desorption behaviors of r adionuclides such as cobalt (Co), strontium (Sr), and cesium (Cs) from the soil contaminated with them were experimentally investigated and the effectiveness of CMCD as a desorbent was evaluated. The desorption equilibrium of used radionuclides could be achieved within 1~3 hr and the desorption ratio from kaolin was higher than that from natural soil. The addition of CMCD of 2 g/L increased the desorption ratio by 5~20 % and the desorption ratio of used r adionuclides was shown in the order of Co > Cs > Sr. The experimental desorption data were fitted successfully by pseudo-second order kinetic model and the desorption rate of the r adionuclides was shown in the order of Cs > Co > Sr. Hysteresis between adsorption and desorption of the r adionuclides, as shown in the order of Sr > Co > Cs, increased as the desorption rate decreased. Consequently, it could be considered that the desorption rate was one of the significant factors of the hysteresis. The addition of CMCD as desorbent increased the amount of desorbed radionuclides and decreased the hysteresis. However, the CMCD could not completely desorb the radionuclides from soils even though the excess of CMCD was added.

Inhibition of Enzymatic Degradation of Leucine Enkephalin and $[D-Ala^2]$-Leucine Enkephalinamide in Various Rabbit Mucosal Extracts by Inhibitors (효소 억제제에 의한 토끼의 점막 추출액중 로이신엔케팔린 및 [D-알라$^2$-로이신엔케팔린아미드의 분해 억제)

  • Chun, In-Koo;Park, In-Sook;Hyun, Jeen
    • Journal of Pharmaceutical Investigation
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    • v.26 no.3
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    • pp.175-185
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    • 1996
  • To inhibit the enzymatic degradation of leucine enkephalin (Leu-Enk) and its synthetic analog. $[D-ala^2]$-leucine enkephalinamide (YAGFL), in the nasal, rectal and vaginal mucosal and serosal extracts of rabbits, effects of enzyme inhibitors such as amastatin (AM), puromycin (PM), thiorphan (TP), thimerosal (TM), EDTA, N-carboxymethyl-Phe-Leu (CPL), phenylethyl alcohol (PEA), phenylmercuric acetate (PMA), benzalkonium chloride (BC) and modified cyclodextrins, alone or in combination, were observed by assaying the pentapeptides staying intact during incubation. Mucosa extracts were prepared by exposing freshly-excised mucosal specimens mounted on Valia-Chien cells to isotonic phosphate buffer while stirring. The degradation of Leu-Enk and YAGFL followed the apparent first-order kinetics. The half-lives (mean) in the nasal, rectal and vaginal mucosal extracts were found to be 1.07, 0.33 and 1.14 hr for Leu-Enk, and 16.9, 6.2 and 6.8 hr for YAGFL, respectively. AM or PM, which is an aminopeptidase inhibitor, did not show a sufficient inhibition of Leu-Enk $(50\;{\mu}g/ml)$ degradation in all kinds of extracts. $Dimethyl-{\beta}-cyclodextrin\;(DM-{\beta}-CyD)$ decreased the degradation rate constants of Leu-Enk about 2 or 3 times, comparing with no additive. However, the use of mixed inhibitors of AM $(50\;{\mu}M)$/TM (0.25 mM)/EDTA (5 mM) resulted in a full stabilization of Leu-Enk by decreasing the degradation rate constants 67.3, 161.3 and 113.8 times far the nasal, rectal and vaginal mucosal extracts, respectively, comparing with no inhibitor. With mixed inhibitors, Leu-Enk remained intact more than 90% after 6 hr-incubation. In the stabilization of YAGFL, hM, TP or CPL alone showed little efffct, and some additives demonstrated a considerable inhibition of YAGFL degradation in the rank order of TM > BC > EDTA. However, the addition of mixed inhibitors such as TM (0.5 mM) and EDTA (5 mM) into the extracts protected YAGFL from the degradation by more than 85% even after 24 hr-incubation, suggesting almost complete inhibition of YAGFL degradation in the extract. On the other hand, $DM-{\beta}-CyD\;or\;hydroxypropyl-{\beta}-cyclodextrin$ (10%) were also found to retard enzymatic degradation rates of YAGFL markedly, and resulted in staying intact more than 80% of YAGFL in the nasal and vaginal mucosal extracts, and more than 60% in the rectal mucosal extract after 16 hr-incubation.

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Saprolegnia ferax에 의한$\beta$-amylase의 생산 및 특성

  • Bai, Suk;Cho, Nam-Chul;Chun, Soon-Bai
    • Microbiology and Biotechnology Letters
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    • v.25 no.2
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    • pp.109-114
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    • 1997
  • The Oomycete Saprolegnia ferax produces an extracellular $\beta$-amylase, Maximum enzyme yield was attained after 7 days of growth in YNB starch medium (pH 6.5) at 25$\circ$C. The amylase was pu- rified 24-fold by ultrafitration, HPLC DEAE column and HPLC gel filtration. The purfied enzyme was a monomeric glycoprotein with a molecular weight of about 44,000 dalton. The pH and temperature optima were 6.5 and 50$\circ$C, respectively. The enzyme was fairly stable up to 50$\circ$C and at acidic pH region (pH 4.0-7.0). The apparent Km and Vmax values of the enzyme against soluble starch were 0.77 mg/ml and 2,174 $\mu$moles/mg protein, respectively. Amino acid analysis indicated that the enzyme was enriched in alanine, glycine, leucine and acidic amino acid. Starch hydrolysis with the enzyme released maltose but not glucose, whereas maltotriose, Schardinger dextrin ($\alpha$-cyclodextrin) and pullulan were not hydrolysed by the enzyme. The enzyme was inhibited by Schardinger dextrin, p-chloromercuribenzoate(PCMB), CU$^{2+}$' and Hg$^{2+}$. Inhibition of the enzyme by PCMB could be reversed by the addition of cysteine and mercaptoethanol.

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Chiral Purity Test of Bevantolol by Capillaryelectrophoresis and High Performance Liquid Chromatography

  • Long, Pham Hai;Trung, Tran Quoc;Oh, Joung-Won;Kim, Kyeong-Ho
    • Archives of Pharmacal Research
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    • v.29 no.9
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    • pp.808-813
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    • 2006
  • Two methods for the chiral purity determination of bevantolol were developed, namely capillary electrophoresis (CE) using carboxymethyl-${\beta}$-cyclodextrin (CM-${\beta}$-CD) as a chiral selector and high-perfomance liquid chromatography (HPLC) using a chiral stationary phase. In the HPLC method, the separation of bevantolol enantiomers was performed on a Chiralpak AD-H column by isocratic elution with n-hexane-ethanol-diethylamine (10:90:0.1, v/v/v) as mobile phase. In the CE method, bevantolol enantiomers were separated on an uncoated fused silica capillary with 50 mM amonium phosphate dibasic adjusted to a pH 6.5 with phosphoric acid containing 15 mM CM-${\beta}$-CD as running buffer. Validation data such as linearity, recovery, detection limit, and precision of the two methods are presented. The detection limits of S-(-)-bevantolol were 0.1% and 0.05% for CE and HPLC method, respectively and R-(+)-bevantolol were 0.15% and 0.05% for CE and HPLC method, respectively. There was generally good agreement between the HPLC and CE results.

달맞이꽃 종자유를 첨가한 호상요구르트의 이화학적 변화와 물성 및 관능적 특성에 관한 연구

  • Lee, Su-Jeong;An, Jeong-Jwa;Gwak, Hae-Su
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2004.05a
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    • pp.330-333
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    • 2004
  • 본 연구는 ${\beta}$-cyclodextrin 처리를 이용하여 우유에서 cholesterol을 제거하여 호상요구르트를 제조하고 혈중 콜레스테롤 저하 물질인 달맞이꽃 종자유(EPO)의 양을 다르게 첨가하여 호상요구르트의 저장기간 중 이화학적 변화와 물성 및 관능적 특성을 살펴보았으며, 그 결과 pH는 저장기간 15일이 경과함에 따라 모든 군에서 pH의 저하가 일어났고, 각 실험군 간 유의적 차이는 없었다. 마찬가지로 산도도 저장기간 15일이 경과함에 따라 모든 실험군에서 계속적인 증가가 나타났으며, 실험군간 유의적 차이는 없었다. 지방산화도측정결과 TBA가(535nm)는 저장 0일에 0.045에서 저장 15일에 0.196까지 증가하였고, EPO 첨가 호상요구르트는 0.188까지 증가하였으나 실험군간 유의적 차이는 보이지 않았다. 점도는 ${\beta}$-CD를 처리하여 2% EPO를 첨가한 호상요구르트가 저장 0일에 3.7에서 저장 15일에 8.4로 가장 큰 점도 감소를 나타내었고, 저장 15일 동안 모든 군에서 점도감소가 나타났다. 관능검사결과 ${\beta}$-CD처리하여 EPO를 첨가한 호상요구르트의 산패취와 산패한 맛이 control보다 높았지만 저장기간이 지날수록 점차 낮아졌고, 신맛과 쓴맛은 control과 유사하게 나타났다. 결론적으로 EPO를 첨가한 호상요구르트는 이화학적 변화와 물성 및 관능적으로 긍정적인 결과로 나타나 산업화의 가능성을 보였다.

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The Influence of Temperature, Ultrasonication and Chiral Mobile Phase Additives on Chiral Separation: Predominant Influence of β-Cyclodextrin Chiral Mobile Phase Additive Under Ultrasonic Irradiation

  • Lee, Jae Hwan;Ryoo, Jae Jeong
    • Bulletin of the Korean Chemical Society
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    • v.33 no.12
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    • pp.4141-4144
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    • 2012
  • This paper introduces a technique for resolving amino acids that combines the advantages of the conventional CSP (chiral stationary phase) method with the CMPA (chiral mobile phase additive) method. A commercially available chiral crown ether column, CROWNPAK CR(+), was used as the CSP and three cyclodextrins (${\beta}$-CD, ${\gamma}$-CD, HP-${\beta}$-CD) were used as the mobile phase additives. Chromatographic resolution was performed at $25^{\circ}C$ and $50^{\circ}C$ with or without sonication. A comparison of the chromatographic results under ultrasonic conditions with those under non-ultrasonic conditions showed that ultrasound decreased the elution time and enantioselectivity at all temperatures. In the case of the ${\beta}$-CD mobile phase additive, the elution time and enantioselectivity under ultrasonic condition were significantly higher than under non-sonic condition at all temperatures. Commercially available Chiralpak AD, Whelk-O2 and Pirkle 1-J columns were used as CSPs to examine more meticulously the effects of ultrasonication and temperature on the optical resolution. The optical resolution of some chiral samples analyzed at $25^{\circ}C$ and $50^{\circ}C$ with or without sonication was compared. As in the previous case, the enantioselectivity was lower at $25^{\circ}C$ but similar enantioselectivity was observed at $50^{\circ}C$.

Production of 2-O-\alpha-D- Glucopyranosl L-Ascorbic Acid by Cyclodextrin Glucanotransferase from Paenibacillus sp. JB-13 (Paenibacillus sp. JB-13의 Cyclodextrin glucanotransferase에 의한 2-O-\alpha-D- Glucopyranosl L-Ascorbic acid 생산)

  • Bae, Kyung-Mi;Kang, Yong;Jun, Hong-Ki
    • Microbiology and Biotechnology Letters
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    • v.29 no.1
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    • pp.31-36
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    • 2001
  • Paenibacillus sp. JB-13 producing the cyclodextrin glucan-otransferase(CGTase) [EC 2.4.1.19] that glucosylated ascorbic acid(AA) at the C-2 position was isolated form soil and the optimal conditions for the production of 2-O-$\alpha$-D- Glucopyranosl L-Ascorbic acid(AA-2G) with CGTase were investigated. CGTase produced AA-2G efficiently using dextrin as a substrate and AA as an aceptor. Several AA-2-oilgosaccharides(AA-2Gs) were also produced in this reaction mixture, and these were efficiently hydro-lyzed to AA-2G and glucose by the treatment with glucoamylase. The optimal temperature for AA-2G production was $37^{\circ}C$ and the optimal pH was around 6.5. CGTase also utilized $\alpha$-,$\beta$-,${\gamma}$-CDs, soluble starch, com statch, dia-static solution from rice and diastatic solution from malt as substrate, but not glucose. The reaction mixture for the maximal production of AA-2G was following; 15% total substrate concentration, 2,500 units/ml of CGTase and a mixing ration of 3:2(g of AA: g of dextrin). Under this condition, 56 mM of AA-2G ,which corresponded to 12.4% yield based on AA. was produced after incubation for 44 hrs at $37^{\circ}C$ and pH 6.5.

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Sensory Evaluation and Bioavailability of Red Ginseng Extract(Rg1, Rb1) by Complexation with ${\gamma}$-Cyclodextrin (${\gamma}$-cyclodextrin으로 포접한 홍삼추출물의 관능평가 및 Rg1, Rb1의 생체이용율)

  • Lee, Seung-Hyun;Park, Ji-Ho;Cho, Nam-Suk;Yu, Heui-Jong;You, Sung-Kyun;Cho, Cheong-Weon;Kim, Dong-Chool;Kim, Young-Heui;Kim, Ki-Ho
    • Korean Journal of Food Science and Technology
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    • v.41 no.1
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    • pp.106-110
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    • 2009
  • In order to reduce the bitter taste and improve the bioavailability of red ginseng extract(RGE), inclusion complexes (RGE-CD) of the extract with ${\alpha}-,\;{\beta}-,\;{\gamma}$-cyclodextrin were prepared and studied for their sensory quality and bioavailability compared to RGE. By complexation, the bitter taste-reducing efficacies of ${\alpha}$-CD and ${\beta}$-CD were much lower than that of ${\gamma}$-CD. In comparative sensory analysis for the bitter taste, RGE-${\gamma}$-CD10, prepared using 10%(w/w) of ${\gamma}$-CD, showed a score of 1.93(decreased by about 78%) compared to RGE as the control. In addition, in sensory analysis for flavor, RGE-${\gamma}$-CD10showed a score of 5.60. Upon increasing the amount of ${\gamma}$-CD to 15%(w/w) and 20%(w/w), respectively, the bitter taste of RGE-${\gamma}$-CD was removed and the flavor of RGE disappeared(scores of 2.67 and 1.67, respectively). Therefore RGE-${\gamma}$-CD10 was chosen as an optimum. The same dosages of RGE and RGE-${\gamma}$-CD10 were orally administered to SD(Sprague-Dawley) rats on a saponin basis, and the plasma concentrations of ginsenoside Rg1 and Rb1 were measured over time to estimate the average AUC(area under the plasma concentration versus time curve) of the ginsenosides. After the oral administration, there were no significant differences in the AUC values of the RGE and RGE-${\gamma}$-CD 10 groups for ginsenoside Rg1. However, AUC values for ginsenoside Rb1 were $25.8{\mu}g{\cdot}hr/mL$ in the RGE group and $81.5{\mu}g{\cdot}hr/mL$ in the RGE-${\gamma}$-CD 10 group, respectively. Therefore, the bioavailability of ginsenoside Rb1 in the RGE-${\gamma}$-CD 10 group was significantly higher by up to 315% compared with that in the RGE group(p = 0.0029). These results show that the bitter taste of RGE can be simultaneously removed by the complexation of RGE and ${\gamma}$-CD(RGE-${\gamma}$-CD) along with increased bioavailability.

Improved Stability of Liposome by Association of Amphiphilic Polyelectrolytes (양친매성 고분자전해질 도입을 통한 리포좀의 안정도 증진에 관한 연구)

  • Cho, Eun-Chul;Lim, Hyung-Jun;Kim, Jun-Oh;Chang, Ih-Seop
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.33 no.1 s.60
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    • pp.1-6
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    • 2007
  • It has been generally known that liposomes become unstable when they contain cyclodextrins (CDs). Our present studies demonstrate that these liposomes can be stable by association of amphiphilic polyelectrolytes. Transmission electron microscopy and photocorrelation spectroscopy results showed that polymer-associated liposomes containing CDs (${\beta}-CD$(${\beta}CD$) and hydroxypropyl-${\beta}CD$ ($HP{\beta}CD$)) were more stable than phosphatidylcholine (PC)-cholesterol (Chol) liposomes containing these CDs. We also compared the stability of PC-Chol liposomes with polymer-associated liposomes containing $HP{\beta}CD$ complexed with water-insoluble drug, rhaponticin (Rh). Two liposomes were relatively stable when $HP{\beta}CD$ did not contain Rh, but Rh-$HP{\beta}CD$ complexes triggered the disruption of PC-Chol liposomes. In contrast, polymer-associated Liposomes containing Rh-$HP{\beta}CD$ complexes maintained its stability over 6 months. The skin permeation test demonstrated that drugs solubilized by CDs were delivered better into the skin of guinea pig by using polymer-associated liposomes than by using PC-Chol liposomes. Above results showed that polymer-associated liposomes gave an effective way to stabilize the liposomes containing drug-loaded CDs, which gives an application of liposomes in drug delivery systems.

Purification and Characterization of Two Extracellular Glucoamylase Isozymes from Lipomyces kononenkoae CBS 5608 Mutant

  • Chun, Soon-Bai;Bai, Suk;Im, Suhn-Young;Choi, Won-Ki;Lee, Jin-Jong
    • BMB Reports
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    • v.28 no.5
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    • pp.375-381
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    • 1995
  • Two forms of glucoamylase (GI and GII) from starch-grown Lipomyces kononenkoae CBS 5608 mutant were purified to apparent homogeneity by means of ultrafiltration, Sephacryl S-200 gel filtration and DEAE Sephadex A-50 chromatography. The apparent molecular weight was calculated as ca. 150 kDa for GI and ca. 128 kDa for GII, respectively. Both enzymes were glycoproteins with isoelectric points of 5.6 (GI) and 5.4 (GII). They had a pH optimun of 4.5 and were stable from pH 5 to 8. The temperature optimum for both enzymes was $60^{\circ}C$, but they were rapidly inactivated above $70^{\circ}C$. The $K_m$ values toward starch were estimated to be 6.57 mg per ml for GI and 4.52 mg per ml for GII, and the $V_{max}$ values were 16.28 ${\mu}M$ per mg for GI and 32.25 ${\mu}M$ per mg for GII, respectively. The $K_m$ and $V_{max}$ values of GII for ${\alpha}-$ or ${\beta}-cyclodextrin$ were estimated to be 0.15 mg per ml and 2.0 mg per ml, respectively ($K_m$) and 1.02 ${\mu}M$ per mg or 1.02 ${\mu}M$ per mg, respectively ($V_{max}$). Neither enzyme exhibited pullulanase activity but they released only glucose from starch or cyclodextrin. Amino acid analysis indicated that both glucoamylases were enriched in proline and acid amino acids. Glucoamylase GII strongly cross-reacted with a monoclonal antibody raised against GI enzymes, and the two enzymes shared very similar amino acid composition. Western blot analysis indicated that L. kononenkoae CBS 5608 mutant produced two forms of glucoamylase on starch, and that synthesis of them was subject to glucose repression.

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