• Archives of Pharmacal Research
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• v.13 no.1
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• pp.64-68
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• 1990

The stabilization effect of .alpha.-tocopherol incorporated into liposomal phospholipid membrane was investigated by fluorospectrophotometry and UV-visible spectretarded by the presence of .alpha.-tocopherol in the bilayer of liposomal phospholipid membrane relative to cholesterol-containing liposomes and pure phospholipid liposomes. .alpha.-tocopherol-containing liposomes prolonged the oxidation of liposomes-embedded heme as those of cholesterol-containing liposomes and pure phospholipid liposomes. Thus .alpha.-tocopherol-containing liposomes may be useful for the carrier systems of nutrients and drugs to phospholipid bilayer and stabilized liposomes.

• Journal of Nutrition and Health
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• v.27 no.5
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• pp.419-428
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• 1994

To investigate the effect of dietary menhaden oil on protein kinase C (PKC) activity and membrane phospholipid composition in epidermal cells, female BALB/C mice were fed either menhaden oil or corn oil with two different levels(5% or 20%) for 6 weeks. Membrane phosphatidycholine(PC) was decreased in menhaden oil-fed group. Eicosapentaenoic acid(EPA) and Docosahexaenoic acid(DHA) were only presented in the acyl chain of membrane phospholipid of menhaden oil-fed mice, so that membrane fluidity of the group could be different from the other group. Both cytosolic and membrane-associated PKC activity in epidermal cells were decreased in menhaden oil-fed mice when compare with corn oil-fed mice. Furthermore, rate of PKC transfer from cytosol to membrane in menhaden oil-fed group was not as fast as in corn oil-fed group. Based on these observations, dietary menhaden oil might act differently from other dietary fat in carcinogenesis.

• 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.

• Bulletin of the Korean Chemical Society
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• v.27 no.3
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• pp.386-388
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• 2006

Membrane proteins in highly oriented lipid bilayer samples are useful for membrane protein structure determination. We used in the past planar lipid bilayers which were aligned and supported on the glass slide. These samples were mechanically aligned in a magnetic field. However, these stacks of glass slides with planar lipid bilayers are not well suited for use with a commercial solid-state NMR probe with a round coil. Therefore, a homebuilt solid-state NMR probe was built and used with a stack of thin glass plates wherein the RF coil was wrapped directly around the flat square sample. Recently, we began to use magnetically aligned bicelles that are suitable for the structure determination of membrane proteins by solid-state NMR spectroscopy without any effort to build a flat square coil probe. These bicelle samples are well suited for use with a commercial solidstate NMR probe with a round coil, are very easy to prepare and are very stable, so that they can be kept for more than a year. In this paper, we present the solid-state NMR spectra of optimized and magnetically oriented bicelle samples of membrane proteins.

• Journal of the Korean Applied Science and Technology
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• v.13 no.3
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• pp.43-49
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• 1996

Metachromatic properties of admixture of thionine and methylene blue(MB) in aqueous solution and phospholipid bilayer membrane have been studied by absorption spectroscopy. When thionine and MB were mixed, new coaggregate has been formed because of MB was redistributed to thionine aggregate. In phosphlipid bilayer membrane system, the highly concentrated thionine was easily formed the coaggregation with MB moiety independent of MB concentration, and absorption band of admixture were more transferred to short wavelength than aqueous system. In monomeric thionine concentration, the coaggregation band was observed at the middle wavelength between the site of monomeric thionine and the site of dimeric MB in the presence of lipid bilayer membrane.

• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.459-468
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• 1984

The currently accepted model of membrane structure proposes a dynamic, asymmetric lipid matrix of phospholipids and cholesterol with globular proteins embedded across the membrane to various degrees. Most phospholipids are in the bilayer arrangement and also closely associated with integral membrane proteins or loosely associated with peripheral proteins. Biological functions of membrane, such as membrane-bound enzyme functions and transport systems, are influenced by the membrane physical properties, which are determined by fatty acid composition of phospholipids, polar head group composition and membrane cholesterol content. Polar and non-polar region of the phospholipid molecule can interact, with changes in the conformation of a membrane-associated protein altering either its catalytic activity or the protein's interaction with other membrane proteins. Mammalian dietary studies attempted to change the lipid composition of a few cell membranes have shown comparisons, using essential fatty acid-deficient diets. In recent years, Clandinin and a few other workers have pioneered the study proving the influence of dietary fat fed in a nutritionally complete diet on composition of phospholipid classes of cell membrane. Modulation caused by diet fat was rapid and reversible in phospholipid fatty acyl composition of membranes of cardiac mitochondria, liver cell, brain synaptosome and lymphocytes. These changes were at the same time, accompanied by variety of membrane associated functions controlled by membrane-bound enzymes, tranporter and receptor proteins. The findings suggest the basic concept of the necessity of dietary fatty acid balance if consistency of optimal membrane structural lipid composition is to be maintained, as well as the overall inadequacy of describing the nutritional-biochemical quality of a dietary fat solely by its content of linoleic acid. Furthermore, they give light on the possible application to clinical and preventive medicine.

• Textile Coloration and Finishing
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• v.6 no.4
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• pp.40-45
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• 1994

To improve the blood compatibility of cellulose membrane, 2-(methacryloyloxy)ethyl-2-(trimethylammonium)ethyl phosphate(MTP), which is a methacrylate with phospholipid polar group, and glycidyl methacrylate(GMA) were grafted simultaneously on the surface of membrane and the biocompatibility of grafted membrane was investigated. There was no difference of permeability between the MTP and GMA-grafted and the original cellulose membrane. The permeation pathway for a solute whose molecular weight was above 10$^{4}$ is maintained after grafting on the surface of membrane. The cellulose membrane grafted with MTP and GMA effectively suppressed thrombogenicity for the rabbit blood. This effect became more clear with increasing the surface distribution of phospholipid polar groups.

• 대한약리학회:학술대회논문집
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• 2006.10a
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• pp.110.2-110.2
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• 2006

• Proceedings of the Korean Biophysical Society Conference
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• 1998.06a
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• pp.16-16
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• 1998

The role of phospholipids in the membrane binding and subsequent insertion of the microsomal protein rabbit cytochrome P450 (P450) lA2 into phospholipid bilayers was investigated. The insertion of P450 lA2 into phospholipid bilayers was determined by the amount of quenching of Trp fluorescence of P450 lA2 by pyrene and brominated and doxyl-labeled phospholipids.(omitted)

• 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)