• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.508-517
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• 1998

We investigated the effects of godulbaegi extracts on the physiochemical properties of biological membranes as membrane stability and fluidity employing the phospholipid liposomal membrances as a biomembrane-mimetic system. The addition of the godulbaegi extracts to the phospholipid exterted great effects stagbilized the barrier function of the liposomal membranes in proportion to the concentration of the additive and significantly increased the membranes fluidity. The values of the fluorescence polarization of 1,6-diphenyl 1,3,5-hexatriene (DPH) decreased gradually as the temperature increased, and decreased abruptly near the phase transition temperature (Tm) of the liposome from gel to liquid crystalline state as usual. These results suggest that the activities of the godulbaegi extracts to enhance the stability and fluidity of the liposomal membranes have implication in their biological activities.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.221.1-221.1
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• 2003

This research was designed to investigate the effects of Bassica oleracea L. (BO) fractions on the membrane fluidity of the liposomal phospholipid membranes. The sample BO was extracted and fractionated to six different types. methanol(BOM), hexane(BOMH). ethylether(BOMEE), etylacetate(BOMEA), butanol(BOMB) and aqueous(BOMA) fractions. The fluidity of dipalmitoylphosphatidylcholine(DPPC) liposomal membranes incorporated with BO fraction was measured by means of high-sensitivity differential scanning calorimetry(DSC). (omitted)

• Textile Coloration and Finishing
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• v.7 no.2
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• pp.63-69
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• 1995

To improve the blood compatibility of chitosan membranes, 2-(methacryloyloxy)-ethyl-2-(trimethylammonium)ethyl phosphate(MTP), which is a methacrylate with phospholipid polar groups, was grafted on the surface of chitosan membranes and the biocompatibility of MTP-grafted chitosan membranes was investigated. The permeation coefficient gradually decreased with increasing in molecular weights of biocomponents below 10$^{4}$, and drastically decreased above 10$^{4}$. This result corresponds with the permeability of solutes in case of hemodialysis membranes. The MTP-grafted chitosan membranes displayed less blood cell adhesion than the chitosan membranes. This may due to the formation of biomembrane4ike surface by adsorption and arrangement of phospholipid molecules from serum onto the MTP copolymer surface.

• Journal of the Korean Chemical Society
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• v.67 no.2
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• pp.89-98
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• 2023

The cell membrane, also known as the biological membrane, surrounds every living cell. The main components of cell membranes are lipids and therefore called as lipid membranes. These membranes are mainly made up of a two-dimensional lipid bilayer along with integral and peripheral proteins. The complex nature of lipid membranes makes it difficult to study and hence artificial lipid membranes are prepared which mimic the original lipid membranes. These artificial lipid membranes are prepared from phospholipid vesicles (liposomes). The liposomes are formed when self-forming phospholipid bilayer comes in contact with water. Liposomes can be unilamellar or multilamellar vesicles which comprises of phospholipids that can be produced naturally or synthetically. The phospholipids are non-toxic, biodegradable and are readily produced on a large scale. These liposomes are mostly used in the drug delivery systems. This paper offers comprehensive literature with insights on developing basic understanding of lipid membranes from its structure, organization, and phase behavior to its potential use in biomedical applications. The progress in the field of artificial membrane models considering methods of preparation of liposomes for mimicking lipid membranes, interactions between the lipid membranes, and characterizing techniques such as UV-visible, FTIR, Calorimetry and X-ray diffraction are explained in a concise manner.

• Archives of Pharmacal Research
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• v.15 no.4
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• pp.309-316
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• 1992

The effects of lipid peroxidation on the fluidity of the lipid bilayers of the human erythrocyte ghosts and egg-lecithin phospholipid liposomes have been studied. For the measurements of the peroxidation extent and the fluidity of the membranes, the thiobarbituric acid-reactive substances and the fluorescence depolarization of 1, 6-diphynyl-1, 3, 5-hexatriene labelled into the membrane were employed, respectively. The lipid peroxidation was performed in hypoxanthine/xanthine oxidase/ferrous ion, and hydrogen peroxide/ferrous ion systems. The results of these experiments show that both of the xanthine oxidase and hydrogen peroxide systems effectively. The lipid peroxidation decreased the fluidity of the membranes, especially at the very early stage of the peroxidation reaction. The decrease in the fluidity of membrane by the lipid peroxidation has been ascribed to the alteration of the polyunsaturated acyl chains of lipids and cross linkages among the membrane components. However, under drastic condition of lipid peroxidation, tdhe fluidity of the membrane rather increased possibly due to the deterioration of the membrane integrity by the peroxidation. Morphological change of the erythrocyte on peroxidation has also been observed.

• Journal of Environmental Science International
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• v.7 no.1
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• pp.62-66
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• 1998

Toxic Mastoparan B(MP-B) which is purified from the venom of the hornet Vespa basalis is a cationic amphlphilic tetradecapeptide. MP-B and Its Ala-substituted analogues were synthesized by solld phase method and the toxic peptide-membrane interactions were examined by circular dichroism(CD) spectra, fluorescence spectra, and leakage abilities in phospholipid membranes. In the presence of phospholipid vesicles, synthetic MP-B and its analogues formed amphiphilic -helical structures, but in the buffer soletion, those exhibited random coil conformation as measured by CD. Fluorescence spectra of MP-B and its analogues which indicated the binding affinity of peptide on phospholipid vesicles showed that the replacement of Lys at position 2 and 11 with Ala caused a remarkable effect in the blue shalt and that at position 2, in the leakage ability of the peptide.

• Journal of Life Science
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• v.13 no.4
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• pp.463-472
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• 2003

Interactions between factor Va (HFVa) and membrane phosphatidylserine (PS) regulate the activity of the prothrombinase complex. I have previously shown that two solvent exposed hydrophobic residues located in the C2-domain, Trp2063 and Trp2064, are required for binding to immobilized PS and for expression of procoagulant activity on membranes containing 5% PS. In order to fully define the functional importance of these two residues I have expressed and isolated recombinant factor Va (rHFVa) W2063A/W2064A double mutant. In contrast to the native protein the two glycoforms resulting from alternative glycosylation of Asn2181 eluted as a single peak with rHFVa1 W2063A/W2064A eluting on the leading edge and rHFVa2 W2063A/W2064A eluting on the trailing edge. The double mutant rHFVa2 W2063A/W2064A expressed little or no procoagulant activity on membranes containing 1-10% mol % PS. In contrast, the procoagulant activity of this mutant was slightly greater than the native protein on membranes containing>18 mol % PS. The binding of rHFVa2 W2063A/W2064A to immobilized phospholipid vesicles was markedly reduced compared to the native protein in a surface plasmon resonance binding assay. I conclude that Trp2063 and Trp2064 are required for high affinity binding of factor Va to PS membranes and that this interaction is necessary for assembly of the prothrombinase complex on membranes containing physiological concentrations of PS.

• Archives of Pharmacal Research
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• v.16 no.3
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• pp.191-195
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• 1993

We investigated the effects of n-alkanols on the range and rate of the lateral diffusion of 1, 3-di(1-pyrenyl)propane in the model membranes of total phospholipid fraction extracted from synaptosomal plasma membrane vesicles. n-Akanols increased the range and rate of the lateral diffusion of 1, 3-di(1-pyrenyl)propane in the bulk model membrane structures (inner + outer monolayers) and the potencies of n-alknols up to 1-nonanol increased by 1 order of magnitude as the carbon chain length increases by two carbon atoms. The cut-off phenomenon was reached at 1-decanol, where further icnrease in hydrocarbon length resulted in a decrease in the lateral diffusion. However, significant changes in the 1'/1 value were not observed by methanol (from 100 to 2500 mM), ethanol (from 25 to 800 mM), and 1-propanol (from 10 to 250 mM) over entire concentration.

• Textile Coloration and Finishing
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• v.7 no.3
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• pp.38-43
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• 1995

To improve the biofunctional properties of silk fibroin membranes, 2-(methacryloyloxy)ethyl-2-(trimethylammonium)ethyl phosphate(MTP), which is a methacrylate with phospholipid polar groups grafted and poly(MTP-co-BMA) was coated on the surface of silk fibroin membranes. The permeability and biocompatibility of silk fibroin membranes with phosphoryl choline group were investigated. The permeability of a salt(NaCl) was increased with grafting by MTP. Futhermore, the poly(MTP-co-BMA)-coated silk fibroin membranes displayed less blood cell adhesion than the silk fibroin membranes.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.09a
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• pp.39-39
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• 2001