• Journal of Environmental Science International
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• v.6 no.2
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• pp.189-194
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• 1997

Toxic peptides from hornet venom, mastoparan and mastoparan-B were synthesized us- ing the solid phase peptide synthesis method and investigated the interaction of them with phospholipid bilayer, antibacterial activity, and hemolytic activity. Both toxic peptides could induce dye release at a low concentration in neutral liposome. The binding affinity of mastoparan-B for neutral liposome was smaller than that for acidic one. Mastoparan and mastoparan-B had strong antibacterial activity for gram-positive bacteria, but weak or potent activity for gram-negative ones, respectively. Mastoparan and mastoparan-B lysed erythrocyte very little up to 5 $\mu$M.

• 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 Photoscience
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• v.7 no.2
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• pp.63-66
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• 2000

A study of the interaction between lysozyme and phospholipid liposomes is essential for a systematic approach for understanding the action mechanism of lysozyme. So we want to clarify the interactions of lysozyme with phospholipid liposmes. We observed that lysozyme more interacts with negatively charged liposomes than with neutral liposome. More hydroxy groups of the phospholipid was very important on that interactions. We recognized the importance of electrostatic interactions in the process of fusion induced by lysozyme. As indicated by UV/Vis experiments, leakage and fusion are two uncoupled process.

• BMB Reports
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• v.29 no.4
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• pp.343-352
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• 1996

The biosynthesis of phospholipid and the composition of fatty acid were analyzed in mitochondria isolated from Chlorella ellipsoidea treated with carbon sources (glucose, sucrose, raffinose) during the culture. The growth of Chlorella and total lipid contents in mitochondria treated with various carbon sources was increased to compare with the control. When Chlorella mitochondria was treated with various carbon sources, four kinds of phospholipid were increased predominantly. The major fatty acids utilized for the biosynthesis of the phospholipid were analyzed linoleic acid (average 25.18%) and stearic acid (average 10.52%) in the control. But, it was shown that the major fatty acids in Chlorella mitochondria treated with glucose were stearic acid (average 30.93%), palmitic acid (average 17.47%) and stearic acid (average 20.31%), linoleic acid (average 16.68%) in sucrose treatment and oleic acid (average 17.17%), palmitic acid (average 15.64%) in raffinose treatment.

• Journal of Life Science
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• v.6 no.3
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• pp.165-170
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• 1996

The action of phospholipid on the rhodotorucine A(RH.A) acceptance by heterbasidiomyceteous yeast Rhodosporidium toruloides mating type a cells and the effect of medium composition during sexual differentiation were investigated. Activation of trigger peptidase(TPase)was very sensitive to the originated phospholipid from R. toruloides and was more sensitive to phospholipid liposome made up of phospholipi. Phospholopod present on the membrance of mating type a cells consists of phospatidylglycerol(PG), phosphatidylethanolamine(PE), phospatidylcholine(PC), phospatidylinositol(PI), and phosphatidylserine(PS) of 12.9, suprisingly 45.4, 11.0, and 13.9%, respectively. As the result of using C-1 and N-1 mediums which limited C and N sources capable of inhibiting the synthesis of phospholipid, it resulted inhibiting sexual dlfferentiation and production of Rh.A from mating type Acells.

• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.125-129
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• 1999

The influence of dietary cholesterol on phospolipid metabolism in rat liver microsmes was studied in rats fed a diet containing fish oil(FO) or beef tallow (BT). The hepatic phospholipid content decreased wherease gepatic triglyceride and cholesterol increased significantly in both groups after cholestered supplementation. Plasma concentrations of phospholipid and traiglyceride increased with cholesterol supplement in both groups while cholesterol decreased only moderately in the FO group. Dietary cholesterol affected microsomal phosphiolpids in liver ; the proportation of phosphatidylcholine decreased in the FO group, an d it also slightly decreased in the BT group at the expense of phosphatidylethanolamine. The activity of CTP : phospocholine cytidylytransferase , the rate-limiting enzyme of phosphatidylcholine synthesis, increased inhepatic mocrosomes whreas it decreased in hepatic cytosol of both groups by cholesterol supplementation. In conclusion, these indicated that the dietary cholesterol profoundly influences phospholipid metabolism in the rat liver.

• Journal of the Korean Applied Science and Technology
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• v.16 no.4
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• pp.281-286
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• 1999

We carried out this subject to observe photoisomerization using 8A5H and phospholipid(DLPC) containing azobenzene group which has reversible to cis-trans by light irradiation. We investigated the photoisomerization and property of the monolayer film on quartz substrate prepared by the mixture of 8A5H and phospholipid deposited using Langmuir-Blodgett(LB) method. It was found that the absorption spectrum of the 8A5H and phospholipid LB monolayer was induced to photoisomerization by alternate light irradiation. And the absorbance of both the solution of mixtures of 8A5H-phospholipid and LB film was reversibly changed by the acid-base exposure and alternate temperatures.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.506-510
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• 2000

This experiment was to determine the usefulness of gum safflower phospholipid as a feed ingredient. Forty female broiler chicks were divided into four groups and fed experimental diets containing following fats and oils; beef tallow (Tallow), the blend of safflower oil and palm oil (SP-oil), gum rapeseed phospholipid (Rap-PL), or gum safflower phospholipid (Saf-PL) for 21days. There were no differences in growth performances among the treatments. Abdominal fat weight tended to be reduced in the chicks fed. phospholipids. The activity of hepatic acetyl-CoA carboxylase was significantly reduced in the Rap-PL and Saf-PL as compared to that of Tallow. Feeding dietary phospholipids resulted in a slight reduction in total fat and triglyceride contents in the breast and thigh muscles. In addition, total fat and triglyceride contents in the thigh muscle were significantly decreased by dietary Saf-PL as compared to those of Tallow. These results suggested that dietary gum phospholipids, either from rapeseed or safflower, had desirable effects of lowing abdominal and muscle fats, and could be used as a feed ingredient for broiler diets.

• Food Science of Animal Resources
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• v.18 no.4
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• pp.332-338
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• 1998

This experiment was carried out to investigate the changes in phospholipid and glycolipid of Kaesojoo and Kaesojoo added medicinal herbs during storage(30 days) at 4$^{\circ}C$and -18$^{\circ}C$. Two dogs with 12kg live weight(♀, The Korean Jindo dog Hy-breed, 11∼12 month) were slaughtered to obtain samples. The result obtained were as follows: The saturated fatty acids found in phospholipid of Kaesojoo were palmitic acid, stearic acid, myristic acid, while the unsaturated fatty acid found in phospholipid of Kaesojoo with medicinal herbs were palmitic acid, stearic acid, arachidonic acid, while the unsaturated fatty acid were mostly oleic acid, increased during the period of storage. The saturated fatty acid found in glycolipid obtained from Kaesojoo were mostly oleic acid, linoleic acid and linolenic acid. The saturated fatty acid obtained from Kaesojoo with medicinal herbs were palmitic acid, stearic acid, while the unsaturated fatty acid were mostly oleic acid, linoleic acid and linolenic acid. The rates of changes in unsaturated and saturated fatty acid were higher at 4$^{\circ}C$ than that of -18$^{\circ}C$ during storage.

• Journal of Applied Biological Chemistry
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• v.42 no.2
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• pp.75-80
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• 1999

The effects of dietary n-3 fatty acids, ${\alpha}$-linolenic acid (18:3), eicosapentaenoic acid (EPA, 20:5), and docosahexaenoic acid (DHA, 22:6), on brain phospholipid content and fatty acid composition were compared in rats fed with a diet containing constant ratios of saturated fatty acid/monounsaturated fatty acid/polyunsaturated fatty acid (PUFA) and n-3/n-6. The dietary fat in each diet was added at the level of 10%. In each diet, n-3 PUFA comprised two-thirds of the PUFA and the remaining one-third was linoleic acid (18:2). Dietary fat containing linoleic acid as the sole source of PUFA was also given to the control group. The content of brain phospholipid in the three n-3 PUFA groups was significantly lower than that of the linoleic acid group. This reduction was greater in the EPA and DHA groups than in the ${\alpha}$-linolenic acid group. The decrease in phospholipid content in rats fed n-3 fatty acid-rich diets was largely due to the decrease in the phosphatidylethanolamine fraction. Each dietary n-3 PUFA was found to affect the fatty acid composition of brain phospholipids; the most pronounced alteration was observed in phosphatidylethanolamine fraction. Furthermore, the proportion of DHA in the phosphatidylethanolamine fraction tended to be higher in the DHA group than in other PUFA groups. In conclusion, dietary ${\alpha}$-linolenic acid, EPA and DHA can influence the phospholipid content, phospholipid subclass, and fatty acid composition in rat brain.