• Journal of KIISE:Software and Applications
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• v.31 no.10
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• pp.1332-1344
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• 2004

Upon development of information super-highway and multimedia-related technoiogies in recent years, more efficient technologies to transmit, store and retrieve the multimedia data are required. Among such technologies, firstly, it is common that the semantic-based image retrieval is annotated separately in order to give certain meanings to the image data and the low-level property information that include information about color, texture, and shape Despite the fact that the semantic-based information retrieval has been made by utilizing such vocabulary dictionary as the key words that given, however it brings about a problem that has not yet freed from the limit of the existing keyword-based text information retrieval. The second problem is that it reveals a decreased retrieval performance in the content-based image retrieval system, and is difficult to separate the object from the image that has complex background, and also is difficult to extract an area due to excessive division of those regions. Further, it is difficult to separate the objects from the image that possesses multiple objects in complex scene. To solve the problems, in this paper, I established a content-based retrieval system that can be processed in 5 different steps. The most critical process of those 5 steps is that among RGB images, the one that has the largest and the smallest background are to be extracted. Particularly. I propose the method that extracts the subject as well as the background by using an Image, which has the largest background. Also, to solve the second problem, I propose the method in which multiple objects are separated using RGB channel selection techniques having optimized the excessive division of area by utilizing Watermerge's threshold value with the object separation using the method of RGB channels separation. The tests proved that the methods proposed by me were superior to the existing methods in terms of retrieval performances insomuch as to replace those methods that developed for the purpose of retrieving those complex objects that used to be difficult to retrieve up until now.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.391-397
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• 2013

A putative cyclomaltodextrinase (LLCD) gene was cloned from the genome of Lactococcus lactis subsp. lactis KCTC 3769 (ATCC 19435), which encodes 584 amino acids with the predicted molecular mass of 68.7 kDa. KCTC 3769 shares approximately 40% of amino acid sequence identity with the CDase-family of enzymes. The dimeric enzyme with C-terminal six-histidines was heterologously expressed and purified from recombinant E. coli. LLCD showed the highest activity against ${\beta}$-cyclodextrin (CD) at pH 7.0 and $37^{\circ}C$. In particular, LLCD exhibited extremely low activity against starch and pullulan, while its CD-hydrolyzing activity was about 80 times higher than starch. Due to its much higher activity on CD over starch, LLCD has been identified as a member of CDases. However, LLCD can be distinguished from the other common CDases on the basis of its extremely low hydrolyzing activity against starch, pullulan, and acarbose.

• Food Science and Preservation
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• v.18 no.2
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• pp.208-211
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• 2011

Limonoids are abundant as bitter taste in citrus fruit and other plants. Interestingly. limonoid UDP-glucosyltransferase (LUGT) effectively ameliorates the bitterness from limonoid. The high level of LUGT expression in Escherichia coli can result in the formation of insoluble aggregates known as inclusion bodies. We isolated the soluble LUGT protein when this inclusion body was renaturated with ${\beta}$-cyclidextrin treatment after protein denaturation by urea. Our present results suggest that the isolation of LUGT from inclusion body in cells leads to shed light to characterize the enzyme for food industry purposes.

• Biomolecules & Therapeutics
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• v.21 no.2
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• pp.161-169
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• 2013

The objective of this study was to enhance the oral bioavailability (BA) of zanamivir (ZMR) by increasing its intestinal permeability using permeation enhancers (PE). Four different classes of PEs (Labrasol$^{(R)}$, sodium cholate, sodium caprate, hydroxypropyl ${\beta}$-cyclodextrin) were investigated for their ability to enhance the permeation of ZMR across Caco-2 cell monolayers. The flux and $P_{app}$ of ZMR in the presence of sodium caprate (SC) was significantly higher than other PEs in comparison to control, and was selected for further investigation. All concentrations of SC (10-200 mM) demonstrated enhanced flux of ZMR in comparison to control. The highest flux (13 folds higher than control) was achieved for the formulation with highest SC concentration (200 mM). The relative BA of ZMR formulation containing SC (PO-SC) in plasma at a dose of 10 mg/kg following oral administration in rats was 317.65% in comparison to control formulation (PO-C). Besides, the $AUC_{0-24\;h}$ of ZMR in the lungs following oral administration of PO-SC was $125.22{\pm}27.25$ ng hr $ml^{-1}$ with a $C_{max}$ of $156.00{\pm}24.00$ ng/ml reached at $0.50{\pm}0.00$ h. But, there was no ZMR detected in the lungs following administration of control formulation (PO-C). The findings of this study indicated that the oral formulation PO-SC containing ZMR and SC was able to enhance the BA of ZMR in plasma to an appropriate amount that would make ZMR available in lungs at a concentration higher (>10 ng/ml) than the $IC_{50}$ concentration of influenza virus (0.64-7.9 ng/ml) to exert its therapeutic effect.

• Journal of Pharmaceutical Investigation
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• v.35 no.6
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• pp.417-422
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• 2005

This study was aimed to design and formulate the moisture-activated patches containing ofloxacin and lidocaine for antibacterial and local anesthetic action. The solubility of lidocaine at $32^{\circ}C$ in various vehicles decreased in the rank order of PG $759.5{\pm}44.5\;mg/mL$ > PGL > IPM > PEG 300 > PEG 400 > Ethanol > PGMC > DGME > PGML > OA > $Captex^{\circledR}\;300$ > $Captex^{\circledR}\;200$ > water $(4.0{\pm}0.1\;mg/mL)$. Ofloxacin revealed very low solubility, which the highest solubility was obtained from PEG 400 $(18.7{\pm}6.3\;mg/mL)$ among the vehicles used. The addition of lactic acid increased the solubility of ofloxacin dramatically; the solubility at 5% lactic acid was $133.7{\pm}9.7\;mg/mL$. As $2-hydroxypropyl-{\beta}-cyclodextrin$ was added at the concentrations of 40, 80, 120, 160 and 200 mM, the solubilities of lidocaine and ofloxacin were enhanced up to three and two times, respectively, with concentration-dependent pattern. Gel intermediates for filmtype patches were prepared with mucoadhesive polymer, viscosity builders, lidocaine or ofloxacin at pH values from 5 to 7. Gels were cast onto a release liner and dried at room temperature. Dried patch was attached onto an adhesive backing layer, thus forming a patch system. Patches containing a single drug component were characterized by in vitro measurement of drug release rates through a cellulose barrier membrane. The release study was carried out at $37^{\circ}C$ using a Franz-type cell. Receptor solutions were isotonic phosphate buffers (pH 7.4). Samples $(100\;{\mu}L)$ were taken over 24 hours and quantitated by a verified HPLC method. The releases from all tested were proportional to the square root of time. The release rates were 0.9, 157.3 and $281.7\;{\mu}g/cm^{2}/min^{1/2}$ for the lidocaine patches and 19.8,37.2 and $50.7\;{\mu}g/cm^{2}/min^{1/2}$ for the ofloxacin patches at the concentrations of 0.3, 0.5 and 1 %, respectively. The release rates were dose dependent in both drug patches $(R^{2}\;=\;0.9077\;for\;lidocaine;\;R^{2}\;=\;0.9949\;for\;ofloxacin)$ and those were also thickness-dependent $(R^{2}\;=\;0.9246\;for\;lidocaine;\;R^{2}\;=\;0.9512\;for\;ofloxacin)$.

• Journal of Pharmaceutical Investigation
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• v.39 no.2
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• pp.97-106
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• 2009

Although lovastatin (LS) is widely used in the treatment of hypercholesterolemia, its bioavailability is known to be around 5%. This study was aimed to increase the solubility and dissolution-permeation rates of LS using solid dispersions (SDs) with bile salts. The solubilities of LS in water, aqueous bile salt solutions and non-aqueous vehicles were determined, and effects of bile salts on the cellulose or duodenal permeation of LS from SDs were evaluated using a horizontal permeation system. SDs were prepared at various ratios of LS to carriers, such as sodium deoxycholate (SDC), sodium glycocholate (SGC) and/or 2-hydroxypropyl-$\beta$-cyclodextrin (HPCD). The addition of bile salts (25 mM) in water increased markedly the solubility of LS by the micellar solubilization. Some non-aqueous vehicles were effective in solubilizing LS. From differential scanning calorimetric studies, it was found that the crystallinity of LS in SDs disappeared, indicating a formation of amorphous state. The SDs showed markedly enhanced dissolution compared with those of their physical mixtures (PMs) and drug alone. In the dissolution-permeation studies using a cellulose membrane, the donor and receptor solutions were maintained as a sink condition using pH 7.0 phosphate buffer containing 0.05% sodium lauryl sulfate (SLS). The flux of LS alone was nearly same as that of LS-SDC-HPCD (1:3:6) PM. However, the flux of LS-SDC-HPCD (1:3:6) SD slightly increased compared with drug alone and PM, suggesting that entrapment of LS in micelles does not significantly hinder the permeation across cellulose membrane. In the dissolution-duodenal permeation studies using a LS-HPCD-SDC (1:3:6) SD, the addition of various bile salts in donor solutions (25 mM) enhanced the permeation of LS markedly, and the fluxes were found to be $0.69{\pm}0.41$, $0.87{\pm}0.51$, $0.84{\pm}0.46$, $0.47{\pm}0.17$ and $0.68{\pm}0.32{\mu}g/cm^2/hr$ for sodium cholate (SC), SDC, SGC, sodium taurodeoxycholate (STDC) and sodium taurocholate (STC), respectively. The stepwise increase of donor SGC concentration increased the flux dose-dependently. From the relationship of donor SGC concentration and flux, the concentration of SGC initiating the permeation across the duodenal mucosa was calculated to be 11.1 mM, which is nearly same as the critical micelle concentration (CMC, 11.6 mM) of SGC. However, with no addition of bile salts and below CMC, the permeation was very limited and irratic, indicating that LS itself is very poor permeable. Higher protions of bile salt in SD such as LS-SDC or LS-SGC (1 : 49 and 1 : 69) showed highly promoted fluxes. In conclusion, SD systems with bile salts, which may form their micelles in intestinal fluids, might be a promising means for providing enhanced dissolution and intestinal permeation of practically insoluble and non-absorbable LS.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.56-63
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• 2007

Insulin stimulates the fusion of intracellular vesicles containing glucose transporter 4 (GLUT4) with plasma membrane in adipocytes and muscle cells. Here we show that adipocyte differentiation results in enhanced insulin sensitivity of glucose uptake. On the other hand, glucose uptake in response to platelet-derived growth factor (PDGF) stimulation was markedly reduced by adipocyte differentiation. Expression level of insulin receptor and caveolin-1 was dramatically increased during adipocyte differentiation. Adipocyte differentiation caused :ilightly enhanced activation of acutely transforming retrovirus AKT8 in rodent T cell lymphoma (Akt) by insulin stimulation. However, activation of Akt by PDGF stimulation was largely reduced. Activation of ERK was not detected in both fibroblasts and adipocytes after stimulation with insulin. PDGF-dependent activation of ERK was reduced by adipocyte differentiation. Insulin-dependent glucose uptake was abrogated by LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor, in both fibroblasts and adipocytes. Also disassembly of caveolae structure by $methyl-\beta-cyclodextrin$ caused impairment of Akt activation and glucose uptake. Finally, insulin receptor, Akt, SH2-domain-containing inositol 5-phosphatase 2 (SHIP2), and regulatory subunit of PI3K are localized at lipid raft domain and the translocation was facilitated upon insulin stimulation. Given these results, we suggest that lipid raft provide proper site for insulin action for glucose uptake.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.574-580
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• 1998

The technical feasibility of removing cholesterol from milk fat by supercritical carbon dioxide $(SC-CO_2)$ extraction followed by adsorption on different adsorbents and of fractionating milk fat into different fatty acid composition at $40^{\circ}C/276$ bar was investigated. Cholesterol could be selectively removed from milk fat by adsorption on a typical commercial florisil with $SC-CO_2$ extraction. Lower weight ratio of milk fat feed to florisil showed higher reduction of cholesterol, but gave lower yield in the milk fat fractions. The effective capacity of florisil for removing cholesterol from milk fat was 2.0g/g, which is the ratio of the fat feed to the adsorbent for 89% cholesterol reduction with a fat yield of 57.5%. Fatty acid composition showed higher short-chain and lower unsaturated long-chain fatty acids in the extracted fractions. Milk fat fractionation method by supercritical fluid extraction in coupled with adsorption would appear suitable for removing undesirable ingredients such as cholesterol and for enriching short-chain fatty acids in the fractions.

• Journal of Pharmaceutical Investigation
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• v.29 no.3
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• pp.227-234
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• 1999

Solid dispersions were prepared to increase the dissolution rate of biphenyl dimethyl dicarboxylate (DDB) using water-soluble carriers such as povidone, copolyvidone, $2-hydroxypropyl-{\beta}-cyclodextrin (HPCD)$, sodium salicylate or sodium benzoate by solvent evaporation method. Solid dispersions were characterized by infrared spectrometry, differential scanning calorimetry (DSC) and powder X-ray diffractometry, dissolution and permeation studies. DDB tablets (7.5 mg) were prepared by compressing the powder mixtures composed of solid dispersions, lactose, com starch, crospovidone and magnesium stearate using a single-punch press. DDB capsules (7.5 mg) were also prepared by filling the mixtures in empty hard gelatin capsules (size No.1). From the DSC and powder x-ray diffractometric studies, it was found that DDB was amorphous in the HPCD or copolyvidone solid dispersions. Dissolution rates after 10 min of DDB alone and solid dispersions (1 : 10) in sodium benzoate, sodium salicylate and copolyvidone were 11.8, 23.5, 22.8 and 82.5%, respectively. Dissolution rates of DDB after 30 min from 1 : 10 and 1 : 20 copolyvidone solid dispersions were 80.5 and 95.0%, respectively. For the DDB tablets prepared using solid dispersions (1 : 20), the initial dissolution rate was dependent on carrier material, and was ranked in order, $Kollidon\;30\;{\ll}$ copolyvidone < HPCD. For the HPCD solid dispersion tablets, dissolution rate reached 97.4% after 15 min, but thereafter slowly decreased to 80.7% after 2 hr due to the precipitation of DDB. However, in the case of copolyvidone solid dispersion tablets, dissolution increased linearly and reached 93.4% after 2 hr. Reducing the volume of test medium from 900 to 300 ml markedly decreased the dissolution rate of the tablets containing 1 : 20 HPCD solid dispersions and 1 : 10 copolyvidone solid dispersion. For 1 : 20 copolyvidone solid dispersion tablets, there was no significant change in dissolution rate up to 1 hr with different volumes of test medium. Preparation of the copolyvidone solid dispersion (1 : 20) in capsules markedly delayed the dissolution (31.2 % after 2hr) due to the limited diffusion within capsules. The permeation rate $(13.4\;g/cm^2\;after\;8\;hr)$ of DDB through rabbit duodenal mucosa from copolyvidone solid dispersion (1 : 10) was markedly enhanced, when compared with drug alone or physical mixtures. From overall findings, DDB formulations containing copolyvidone solid dispersions (1 : 20) could be used to remarkably improve the dissolution rate in dosage form of powders and tablets.

• Herbal Formula Science
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• v.31 no.4
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• pp.215-230
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• 2023

Objectives : Schisandra chinensis (Turcz.) Baill contains many nutrients and exhibits high physiological functions. It has been shown that Schisandra seed and pamace contains more nutrients than fruits and thus have higher antioxidant efficacy. In this study, seed and pamace of Schisandra chinensis (Turcz.) Baill (SPSC) were treated with hot-melt extrudate (HME) extrusion to produce water-soluble nanoparticles. Methods : SPSC was treated with HME to prepare nanoparticles. In this process, excipients (hydroxypropyl methylcellulose, pullulan, 2-hydroxylpropyl-beta-cyclodextrin, lecithin) were added to prepare a hydrophilic polymer matrix. To compare and analyze the antioxidant effect and schizandrin content, total flavonoid content, total phenol content and ABTS assay were measured. To confirm the effect of increasing the water solubility of the particles, particle size and water solubility index measurements were performed. The molecular of the material was analyzed using Fourier transform infrared spectroscopy (FT-IR). Results : The particle size of HME extrudates decreased, while total phenols, flavonoids, schizandrin, antioxidant effect, and solubility increased. Through FT-IR, it was confirmed that the SPSC and the extrudate exhibit the same chemical properties. In addition, it was confirmed that when extracted with water, it exhibited a higher antioxidant effect than the ethanol extract. Conclusions : HME technology increased the solubility of SPSC, which are processing by-products, and improved their antioxidant effect to a higher degree. It was confirmed that SPSC could be used as an eco-friendly, high value-added material.