• YAKHAK HOEJI
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• v.38 no.5
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• pp.488-495
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• 1994

To evaluate the feasibility of transmucosal delivery of leucine enkephalin (Leu-Enk) and its synthetic analog, $[D-Ala^2]$-leucine enkephalinamide (YAGFL), their physicochemical stabilities in aqueous buffered solutions were first investigated using a stability indicating high performance liquid chromatography. The degradation of Leu-Enk and YAGFL followed the pseudo-first-order kinetics. From the pH-rate profiles, it was found that the maximal stability of the two pentapeptides was at the pH of about 5.0. The shelf lives $(t_{90%})$ for the degradation of Leu-Enk and YAGFL at pH 5.0 and $40^{\circ}C$ were found to be 48.13 and 50.9 days, respectively. From the temperature dependence of the degradation, activation energies for Leu-Enk and YAGFL were calculated to be 13.61 and 13.47 kcal/mole, respectively. A higher ionic strength and a higher initial peptide concentration in buffered solution slowed the degradation of the two pentapeptides. The addition of 2-hydroxypropyl-${\beta}$-cyclodextrin into the peptide solution did not affect the stability significantly.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.193-201
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• 2000

Partitioning of hydrophobic organic compounds (HOCs) to a biosurfactant, hydroxypropyl-${\beta}$-cyclodextrin (HPCD), was conducted to evaluate the feasibility of using HPCD to remove HOCs from soil/groundwater. HOC partitioning to HPCD was very fast, with over 95% of the complexation occurring within 10 min. Some influence of solution chemistry and HOC concentration on HOC-HPCD complex formation coefficients was observed. HPCD sorption on soil as quantified by both a fluorescence technique and total organic carbon measurements was negligible, indicating no significant affinity of HPCD for the solid phase. Although the HOC solubilization capability of HPCD was lower than that of synthetic surfactants such as SDS and Tween 80, HPCD can be effective in removing sorbed HOCs from a model subsurface environment, primarily because of its negligible sorption to the solid phase (i.e., all the HPCD added facilitates HOC elution). However, in contrast with conventional surfactants, HPCD becomes relatively less effective for HOC partitioning with increasing HOC size and hydrophobicity. Therefore, comparisons between HPCD and synthetic surfactants for enhanced remediation applications must consider the specific HOC(s) present and the potential for surfactant material losses to the solid phase, as well as other more generally recognized considerations such as material costs and potential toxicological effects.

• YAKHAK HOEJI
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• v.50 no.1
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• pp.1-7
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• 2006

The purpose of the present study was to formulate the aqueous solution of 1-cyclopent-3-enylmethyl-6(3,5-dimethyl-benzoyl)-5-ethyl-1H-pyrimidine-2,4-dione (CPD), a novel antivirus compound containing pirimidine structure. For this purpose, the effects of various solubilization agents such as cosolvents [ethanol, propylene glycol (PG), polyethylene glycol 300 (PEG 300), polyethylene glycol 400 (PEG 400), glycerin], surfactants (Tween 80, Cremophor$^{(R)}$ RH40, Cremophor$^{(R)}$ EL, Poloxamer 407, Poloxamer 188) and a complexation agent [hydroxypropyl-${\beta}$-cyclodextrin (HPBCD)] , on the solubility of CPD in aqueous solution were evaluated. The solubility of CPD in water was under $1\;{\mu}g/ml$ at $20^{\circ}C$. Cosolvents such as ethanol, PG, PEG 300, PEG 400 and glycerin did not enhance the solubility of CPD at the $0{\sim}40\%$ concentration range. The solubility of CPD was significantly elevated by the addition of cosolvents over the $80\%$ concentration range. On the other hand, tween 80, Cremophor$^{(R)}$ L, Cremophor$^{(R)}$ RH40, and HPBCD showed enhanced effects on the solubility of CPD. The enhanced effects of Poloxamer 407 or Poloxamer 188 on the CPD solubility were less pronounced compared with tween 80, Cremophor$^{(R)}$ L or Cremophor$^{(R)}$ RH40. As a results, tween 80 aqueous solution was selected as an optimum solvent system. The aqueous solutions containing $20\%$ tween 80 were formulated as a dosing solution containing CPD for its intraperitoneal and intrahypodermic administration, respectively, The formular showed physical stability after stored for 7 days at $4^{\circ}C$.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.19-29
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• 1995

The study was carried out to develop useful formulation for omeprazole(OMP) through OMP-ethylendiamine complex(OMPED), and the pharmaceutical properties of formula were tested to find out the difference in vivo behaviors of formulations between the free and complexed OMP. Oral and suppository dosage forms were also formulated and the dissolution profiles and pharmacokinetic parameters were measured to observe the difference in bioavailability between the free and complex form, and the correlation between dissolution rate and bioavailability was evaluated. The results are summarized as follows; In the case of formulation for oral administration, the release of OMP from enteric OMPED pellets was found satisfactory to the requirement standard and no decomposition of OMP in the pellets was found in acidic solution. Therefore the enteric OMPED pellets are anticipated to be a stable formulation. The release of OMP from OMPED tablet with chitosan as excipient and coated with cellulose acetate phthalate was found to be significantly retarded. The results of bioavailability test for OMP and OMPED tablets with lactose-excipient showed that the AUC value of OMP tablet was $116.89\;{\mu}g\;{\cdot}\;min/ml$, that of OMPED tablet was $161.10\;{\mu}g\;{\cdot}\;min/ml$, respectively. The reason why was thought that OMP decomposes more readily in body than OMPED, and the AUC of the tablet with chitosan-excipient and coated with cellulose acetate phthalate was most enhanced. In the case of bioavailability for suppositories with OMP, $OMP-{\beta}\;-cyclodextrin$ complex and OMPED, the AUC of OMPED suppository was most increased. From the above results, it is thought that the more stable and bioavailable oral or rectal dosage forms could be developed by using the OMPED as a potential OMP complex.

• Journal of Life Science
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• v.8 no.5
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• pp.497-503
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• 1998

Cyclodextrinase from B. stearothemophilus KJ16 that can produce both cyclodextrin(CD) glucanotransferase and cyclodextrinase was purified 87.6-fold with 7% yield by ammonium sulfate precipitation, DEAE-cellulose chromatog-raphy, Sephadex G-100 chromatography, and FPLC. The molecular weight of the purified enzyme was about 68,000 dalton by SDS-PAGE. The optimal pH and temperature were 6.0 and 55$^{\circ}C$, respectively. The enzyme was stable at 5$0^{\circ}C$ for 2 hr in the pH range of 5.5 and 8.5. The enzyme activity was inhibited strongly by mercaptoethanol, di-thiothreitol, p-chloromercuribenzoate, N-bromosuccinimide, $Cu^{+2}$and $Hg^{+2}$. The purified enzyme hydrolyzed CDs with$\gamma$-CD>$\beta$-CD>$\alpha$-CD. The enzyme also hydrolyzed linear maltodextrins and polysaccharides, but the rates of hyd-rolysis for such substrates were slow as compared to that for $\gamma$-CD. The final degradation products with all substrates were maltose and glucose. Maltose was not further hydrolyzed.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.602-607
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• 1993

These studies were conducted to investigates the changes in physicochemical characteristics of Charbori (waxy-barley) and Olbori (normal) during kernel maturation. 1000-kernel weight increased as the barley matured and as the original moisture decreased. The amount of total nitrogen per endosperm was similar in both cultivars. 1000-kernal weight had a correlation coefficient of $r=-0.871^{**}$ with water soluble nitrogen and of $r=-0.894^{**}$ with nitrogen solubility index. At maturity, the starch content of Olbori was 26% higher than Chalbori. Amylose content ranged from 20.4 to 24.7% in Olbori and from 9.9 to 12.9% in Chalbori as the kernel matured. ${\beta}-glucan$ viscosity was no differences at the early stages of development, but at 40 days after heading, was greatly differences between Chalbore and Olbori, 7.9 kand 5.8 cST, respectively. Gelatinization characteristics and other properties of the starch by Amylograph were compared with those of Olbori and Chalbori. The Chalbori starch usually had a lower initial temperature and setback.

• Journal of Microbiology and Biotechnology
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• v.17 no.9
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• pp.1521-1526
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• 2007

A maltogenic amylase gene from Lactobacillus gasseri ATCC33323 (LGMA) was expressed in Lactococcus lactis MG1363 using the P170 expression system. The successful production of recombinant LGMA (rLGMA) was confirmed by the catalytic activity of the enzyme in liquid and solid media. The N-terminal amino acid sequencing analysis of the rLGMA showed that it was Met-Gln-Leu-Ala-Ala-Leu-, which was the same as that of genuine protein, meaning the signal peptide was efficiently cleaved during secretion to the extracellular milieu. The optimal reaction temperature and pH of rLGMA ($55^{\circ}C$ and pH 5, respectively) and enzymatic hydrolysis patterns on various substrates (${\beta}$-cyclodextrin, starch, and pullulan) supported that rLGMA was not only efficiently secreted from the Lactococcus lactis MG1363 but was also functionally active. Finally, the branched maltooligosaccharides were effectively produced from liquefied com starch, by using rLGMA secreted from Lactococcus lactis, with a yield of 53.1%.

• Journal of Pharmaceutical Investigation
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• v.24 no.2
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• pp.57-65
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• 1994

To increase the dissolution rate of practically insoluble biphenyl dimethyl dicarboxylate (DDB), various solid dispersions were prepared with water soluble carriers, such as povidone (PVP K-30), poloxamer 407, sodium deoxycholate (SDC) and polyethylene glycol (PEG) 6000, at drug to carrier ratios of 1:3, 1:5 and 1:10 (w/w) by solvent or fusion method. Dissolution test was performed by the paddle method. The dissolution rate of DDB tablets (25 mg) on market was found to be very low (11.44, 9.02 and 6.42% at pH 1.2, 4.0 and 6.5 after 120 min, respectively). However, dissolution rates of DDB from various solid dispersions were very fast and reached supersaturation within 10 min. DDB-PEG 6000 solid dispersion appeared to be better in enhancing the in vitro dissolution rate than others. Furthermore, the incorporation of DDB and phosphatidylcholine (PC) into ${\beta}-cyclodextrin$ at ratios of 1:2:20, 1:5:20 and 1:10:20 resulted in a 4.9-, 11.2- and 19.6-fold increase in DDB dissolution after 120 min as compared with the pure drug, respectively. This might be attributed to the formation of lipid vesicles which entrapped a certain concentration of DDB during dissolution. On the other hand, the permeation of DDB through rabbit duodenal mucosa was examined using some enhancers such as SDC, sod. glycocholate (SGC) and glycyrrhizic acid ammonium salt (GAA). Only trace amounts of DDB were found to permeate through deuodenal mucosa in the absence of enhancer. SDC was found to markedly decrease the permeation flux of DDB, however, SGC and GAA (5 mM) enhanced the flux of DDB 1.6 and 2.4 times higher as compared with no additive, respectively.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.436-442
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• 2001

Neuropeptide such as calcitonin gene-related peptide and substance P may mediate neurogenic inflammation, but little is known about the regulation of neuropeptide release from rat spinal cord. Eugenol has been reported to reduce odontogenic pain and is known to have a structure similar to capsaicin, a potent stimulant of certain nociceptors. This study was done to examine the effect of capsaicin and eugenol on immunoreactive calcitonin gene-related peptide (iCGRP) release from rat spinal cord and whether eugenol regulates capsaicin-sensitive release of iCCRP or it evokes capsaicin-sensitive release of iCGRP. The dor-sal half of rat lumbar spinal cord was chopped into 200$\mu$m slices. They were superfused (500$\mu$l/min) in vitro with an oxygenated Kreb's buffer. The EC$_{50}$ of capsaicin on iCGRP release was measured. Eugenol (600$\mu$M and 1.2mM) and vehicle (0.02% 2-hydroxyl-$\beta$-cyclodextrin) were administered prior to stimulation of rat lumbar spinal cord with capsaicin. The amount of iCGRP release from rat lumbar spinal cord was measured by radioimmunoassay. The results were as follows : 1. iCGRP release from rat lumbar spinal cord was dependent on concentration of capsaicin. The EC$_{50}$ of capsaicin on iCGRP release was 3$\mu$M. 2. In the vehicle treated group, capsaicin (3$\mu$M) evoked a 14-fold increase over basal iCGRP level. 3. Administration of 600$\mu$M and 1.2mM eugenol evoked a 2.2-fold increase and a 2.3-fold increase over basal iCGRP level respectively. 4. Administration of 600$\mu$M and 1.2mM eugenol increased capsaicin evoked release of iCGRP by more than 50%. These results indicate that eugenol evoke CGRP release from central nervous system and potentiate the pain-inducing action of capsaicin on it.

• BMB Reports
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• v.37 no.4
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• pp.408-415
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• 2004

The expression of the Paenibacillus sp. A11 cyclodextrinase (CDase) gene using the pUC 18 vector in Escherichia coli JM 109 resulted in the formation of an insoluble CDase protein in the cell debris in addition to a soluble CDase protein in the cytoplasm. Unlike the expression in Paenibacillus sp. A11, CDase was primarily observed in cytoplasm. However, by adding 0.5 M sorbitol as an osmolyte, the formation of insoluble CDase was prevented while a three-fold increase in cytoplasmic CDase activity was achieved after a 24 h-induction. The recombinant CDase protein was purified to approximately 14-fold with a 31% recovery to a specific activity of 141 units/mg protein by 40-60% ammonium sulfate precipitation, DEAE-Toyopearl 650 M, and Phenyl Sepharose CL-4B chromatography. It was homogeneous by non-denaturing and SDS-PAGE. The enzyme was a single polypeptide with a molecular weight of 80 kDa, as determined by gel filtration and SDS-PAGE. It showed the highest activity at pH 7.0 and $40^{\circ}C$. The catalytic efficiency ($k_{cat}/K_m$) values for $\alpha$-, $\beta$-, and $\gamma$-CD were $3.0{\times}10^5$, $8.8{\times}10^5$, and $5.5{\times}10^5\;M^{-1}\;min^{-1}$, respectively. The enzyme hydrolyzed CDs and linear maltooligosaccharides to yield maltose and glucose with less amounts of maltotriose and maltotetraose. The rates of hydrolysis for polysaccharides, soluble starch, and pullulan were very low. The cloned CDase was strongly inactivated by N-bromosuccinimide and diethylpyrocarbonate, but activated by dithiothreitol. A comparison of the biochemical properties of the CDases from Paenibacillus sp. A11 and E. coli transformant (pJK 555) indicates that they were almost identical.