• Food Science of Animal Resources
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• v.24 no.1
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• pp.97-102
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• 2004

The objective of this study was to control Kimchi fermentation using pH sensitive bacteriocin entrapping liposome(bacteriocin-liposome). The liposomes were prepared by the reverse-phase evaporation method from a mixture of DPPC(dipalmitoyl phosphatidylcholine, DPPE(dipalmitoyl phosphatidylethanolamine), DOPC(dioleoyl phosphatidylcholine) and cholesterol in a molar ration of 4:2:1:4. The bacteriocin-liposome was disruptured at pH 4 of buffer and was stable at alkaline pHs(6 and 7). Irrespective of the addition of the bacteriocin-liposomes, the pH of every Kimchi sample decreased to 5 during 5 days storage at 5$^{\circ}C$. Kimchi samples treated with bacteriocin-liposomes maintained pH 4 or higher, while Kimchi samples not treated with bacteriocin-liposomes exhibited pH 3.58 or lower. In general, the pH of Kimchi samples stored at 20$^{\circ}C$ decreased faster, compared to that of Kimchi samples stored at 5$^{\circ}C$. The pH of Kimchi samples treated with the bacteriocin-liposomes was 3.9 during 90 days storage, while that of the samples not treated with the bacteriocin-liposomes was 3.68 and 3.32 during 30 days and 90 days storages, respectively. Lactic acid bacteria in Kimchi treated with the bacteriocin-liposome grew relatively slow at 5$^{\circ}C$. The viable cell number of lactic acid bacteria increased up to 4${\times}$10$\^$7/ cells/ml and then decreased to 8${\times}$10$\^$6/ cells/ml during 90 days storage at 5$^{\circ}C$.

• Biomedical Science Letters
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• v.4 no.1
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• pp.35-42
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• 1998

The effects of CRP purified from human ascites fluid on phagocytic activity of the human macrophage were investigated. CRP was purified using affinity chromatography including absorption on p-diazonium phosphocholine or C-polysaccharide coupled sepharose 4B and gel filtration on hydroxylapatite column chromatography. Macrophage was separated ficoll hypaque gradient density and absorption method, and then was confirmed phagocytic uptake test using latex method. CRP was able either to inhibit or to enhance phagocytic activity of human macrophage against bacteria in vitro. The effects of CRP on phagocytic activity of human macrophage were in time and dose-dependent manners. The additional sequence of reaction mixture against bacteria in vitro shows a threshold stimulus on the activation of phagocytic response upon the CRP.

• Journal of Pharmaceutical Investigation
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• v.33 no.3
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• pp.209-213
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• 2003

The objective of this study was to construct the pegylated liposomes containing plasmid DNA with optimal encapsulation efficiency. Plasmid DNA $(pGL2\;clone\;753,\;{\sim}6\;kb)$ was encapsulated by the freeze/thawing method into liposomes composed of 1-palmitoyl-2-oleyl-sn-glycerol-3-phosphocholine (POPC), didodecyl dimethyl ammonium bromide (DDAB), distearoylphosphatidyl ethanolamine polyethylene glycol 2000 (DSPE-PEG 2000) and DSPE-PEG 2000-male-imide. The liposomes containing plasmid DNA were then extruded through two stacked polycarbonate filters with series of different pore sizes to control the liposome size. The plasmid DNA entrapped in the liposomes was separated from free plasmid DNA by Sephadex CL-4B column chromatography. The decreased pore size of polycarbonate filters resulted in the decreased size of liposomes. The encapsulation efficiency was markedly affected by the cationic lipid (DDAB) concentration, but to a low degree by the size of liposomes and by the amount of plasmid DNA.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.874-877
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• 2004

We carried out this subject to observe electrochemical properties of 1,2-dioleoyl-sn- glycero-3-phosphocholine(DOPC) mixed with fatty acid containing azobenzene group by using cyclic voltammetry with a three-electrode system, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode in $NaClO_4$ solution. We investigated the photoisomerization and electrochemical property of the organic ultra thin film of fatty acid containing azobenzene was prepared on the hydrophilic ITO(idium tin oxide) glass plate by LB method. As a result, the absorption spectra of BASH and DOPC of mixture LB films was induced to photoisomerization by alternating irradiation of ultraviolet and visible light. A measuring range was reduced from initial potential to -1350mV, continuously oxidized to 1650 mV and measured to the initial point. The scan rate were 50, 100, 150 and 200 mV/s. As a results, LB films of BASH-DMPC appeared reversible process caused by the reduction-oxidation current from the cyclic voltammogram.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1149-1153
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• 2006

LPC analogues including natural and unnatural LPC, 3-L-2-PC, acetylated LPC and ethylene glycol derivative are prepared from D-mannitol using in convenient procedures by only changing the synthetic sequences, and their protective activities against cecal ligation and puncture (CLP)-induced severe sepsis are compared. The chirality at C2 position in LPC is found to be required as (S)-configuration for sepsis inhibition, comparing from the protection activity between LPC 6 and unnatural LPC 8. The hydroxyl functionality is also very important and required at C2 or C3 position as shown in the protection activities of ethylene glycol analogue 11 and 3-L-2-PC 9.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1263-1269
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• 2004

The objective of this study was to characterize immunoliposomes carrying plasmid DNA with optimal encapsulation efficiency and antibody density. Plasmid DNA was encapsulated by the freezing/thawing method into liposomes composed of POPC (1-palmitoyl-2-oleoyl-sn-glycerol- 3-phosphocholine), DDAB (didodecyl dimethyl ammonium bromide), DSPE-PEG 2000 (distearoyl phosphatidyl ethanolamine polyethylene glycol 2000) and DSPE-PEG 2000-maleimide. The liposomes carrying plasmid DNA were extruded through two stacked polycarbonate filters, of different pore size, to control the liposome size. Then, rat IgG molecules were conjugated to the liposomes. The immunoliposomes containing plasmid DNA were separated from the free plasmid DNA and unconjugated IgG by Sepharose CL-4B column chromatography. The DNA amount encapsulated was affected by DDAB (cationic lipid) concentration, the initial amount of plasmid DNA between 10 ${\mu}g$ and 200 ${\mu}g$, the total lipid amount and plasmid DNA size, but not significantly by liposome size. By varying the ratio of DSPE-PEG 2000-maleimide to IgG, the number of IgG molecules per liposome was changed significantly.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2973-2977
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• 2013

In this study, we developed a liquid crystal (LC)-based optical sensor for monitoring enzymatic activity through orientational changes in liquid crystals (LCs) coupled to the properties of a poly-${\small{L}}$-lysine (PLL)-based polymeric membrane. We prepared a PLL-based polymeric membrane at the planar interface between the thermotropic liquid crystal and aqueous phases. The PLL-based polymeric membrane was obtained by contacting the PLL solution with water immiscible LCs, 4-cyano-4'-pentyl-biphenyl (5CB) doped with adipoyl chloride. We then investigated the membrane properties by examining the permeability of the membrane to phospholipids, 1,2-didodecanoyl-rac-glycero-3-phosphocholine (DLPC). The permeability of the membrane to transport phospholipids was monitored through the orientational transition of 5CB in contact with the dispersions of DLPC. Since trypsin can enzymatically catalyze the hydrolysis of PLL, we incubated an aqueous trypsin solution with the membrane for 2 h at room temperature to cause an increase in the permeability of the polymeric membrane to DLPC. As a result, a bright to dark optical shift of LCs was observed, which implied that an enzymatic reaction between trypsin and PLL-based membrane occurred. Two control experiments using chymotrypsin and bovine serum albumin (BSA) revealed no sign of improved permeability based on the orientational transition of LCs.

• Journal of Pharmaceutical Investigation
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• v.41 no.1
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• pp.19-24
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• 2011

In order to enhance the clinical efficacy of 5-aminolevulinic acid-induced photodynamic therapy (ALA-PDT), liposomal formulations using bulk hydrogenated phospholipids from soybean were introduced. Three types of lipids, S75-3, S100-3, and SL80-3 were used for formulating ALA. The pH of all the liposomal ALA is 4.5~5.5 and the size is 50~200 nm. All the liposomal formulations gave better ex vivo ALA skin penetration using nude mice skin in Franz cell than free ALA did. Among them, SL80-3 including 22% of lyso-phosphocholine achieved excellent ALA penetration when compared with those of S75-3 and S100-3 which have only 1~2% of lyso-phospholipids. S100-3 showed a little better results than S75-3 did. Addition of humectants (glycerine, propylene glycol, butylene glycol, betaine) in liposomal ALA formulated with SL80-3 produced little enhancing effect in ALA penetration. On the other hand, addition of surfactants (Tween 20, 60, Brij 72, 76, 78) in same liposomal system produced significant increase in ALA penetration. Among them, transferosomal system of lyso-phospholipid, SL80-3 and the surfactant, Brij76 showed the highest ALA penetration. Furthermore, this system also established the highest in vivo PpIX biosynthesis in hairy mice skin of C57BL/6. These results concluded that the transferosome of SL80-3 and Brij76 produced the best results in both ALA penetration and PpIX biosynthesis, and proved good correlation between them.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1827-1834
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• 2015

The SMG1 lipase from Malassezia globosa is a newly found mono- and diacylglycerol (DAG) lipase that has a unique lid in the loop conformation that differs from the common alpha-helix lid. In the present study, we characterized the contribution of three residues, L103 and F104 in the lid and F278 in the rim of the binding site groove, on the function of SMG1 lipase. Site-directed mutagenesis was conducted at these sites, and each of the mutants was expressed in the yeast Pichia pastoris, purified, and characterized for their activity toward DAG and p-nitrophenol (pNP) ester. Compared with wild-type SMG1, F278A retained approximately 78% of its activity toward DAG, but only 11% activity toward pNP octanoate (pNP-C8). L103G increased its activity on pNP-C8 by approximately 2-fold, whereas F104G showed an approximate 40% decrease in pNP-C8 activity, and they both showed decreased activity on the DAG emulsion. The deletion of 103-104 retained approximately 30% of its activity toward the DAG emulsion, with an almost complete loss of pNP-C8 activity. The deletion of 103-104 showed a weaker penetration ability to a soybean phosphocholine monolayer than wild-type SMG1. Based on the modulation of the specificity and activity observed, a pNP-C8 binding model for the ester (pNP-C8, N102, and F278 form a flexible bridge) and a specific lipid-anchoring mechanism for DAG (L103 and F104 serve as "anchors" to the lipid interface) were proposed.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.4
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• pp.479-491
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• 1998

In order to know the pathogenesis of adult respiratory distress syndrome (ARDS) in association with the oxidative stress by neutrophils, the role of platelet activating factor (1-0-alkyl-2-acetyl-snglycero-3-phosphocholine, PAF) was investigated during acute lung injury induced by interleukin- $1{\alpha}$ (IL-1) in rats. An insufflation of IL-1 into the rat's trachea increased the acetyltransferase activity in the lung and the increase of PAF content was followed. As evidences of acute lung injury by neutrophilic respiratory burst, lung leak index, myeloperoxidase activity, numbers of neutrophils in the bronchoalveolar lavage fluid, neutrophilic adhesions to endothelial cells and NBT positive neutrophils were increased after IL-1 treatment. In addition, a direct instillation of PAF into the trachea caused acute lung leak and the experimental results showed a similar pattern in comparison with IL-1 induced acute lung injury. For the confirmation of oxidative stress during acute lung leak by IL-1 and PAF, a histochemical electron microscopy was performed. In IL-1 and PAF treated lungs of rats, the deposits of cerrous perhydroxide were found. To elucidate the role of PAF, an intravenous injection of PAF receptor antagonist, WEB 2086 was given immediately after IL-1 or PAF treatment. WEB 2086 decreased the production of hydrogen peroxide and the acute lung leak. In ultrastructural study, WEB 2086 mitigated the pathological changes induced by IL-1 or PAF. The nuclear factor kappa B (NFkB) was activated by PAF and this activation was inhibited by WEB 2086 almost completely. Based on these experimental results, it is suggested that the PAF produced in response to IL-1 through the remodeling pathway has the major role for acute lung injury by neutrophilic respiratory burst. In an additional experiment, we can also come to conclude that the activation of the NFkB by PAF is thought to be the fundamental mechanism to initiate the oxidative stress by neutrophils causing release of proinflammatory cytokines and activation of phospholipase $A_2$.