• Polymer(Korea)
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• v.33 no.2
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• pp.144-152
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• 2009

The thermal and optical properties of poly {1-(cholesteryloxycarbonylalkanoyloxy) ethylene}s (PCALEn, n=2$\sim$8,10, the number of methylene units in the spacer) were investigated. All of the homologues formed monotropic cholesteric phases with left-handed helical structures. PCALEn with n=2 or 10, in constrast with PCALEn with $3{\leq}n{\leq}8$, did not display reflection colors over the full cholesteric range, suggesting that the helical twisting power of the cholesteryl group highly depends on the length of the spacer connecting the cholesteryl group to the polyethylene chain. The glass transition temperatures decreased with increasing n. The isotropic-cholesteric phase transition temperatures decreased with increasing n up to 7 and showed an odd-even effect. However it became almost constant when n is more than 7. This behavior is rationalized in terms of the change in the average shape of the side chain on varing the parity of the spacer. This rationalization also accounts for the observed variation of the entropy gain for the clearing transition. The thermal stability and degree of order in the mesophase and the temperature dependence of the optical pitch observed for PCALEn were significantly different from those reported for cellulose tri(cholesteryloxycarbonyl)alkanoates. The results were discussed in terms of the differences in the chemical structure and flexibility of main chain and the number of the mesogenic units per repeating unit.

• Polymer(Korea)
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• v.32 no.5
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• pp.446-457
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• 2008

Three kinds of hydroxypropyl cellulose (HPC) derivatives: 6- (cholesteryloxycarbonyl) pentoxypropyl celluloses(CHPCs) with degree of esterification(DE) ranging from 0.6 to 3, 6-[4-{4'-(nitrophenylazo)phenoxycarbonyl}] pentoxypropyl celluloses (NHPCs) with DE ranging from 0.4 to 3, and fully 6-(cholesteryloxycarbonyl) pentanoated NHPCs (CNHPCs) were synthesized, and their thermotropic liquid crystalline properties were investigated. All the CHPCs and NHPCs with $DE{\leq}1.7$ formed enantiotropic cholesteric phases, whereas CNHPCs with 6-(cholesteryloxycarbonyl) pentanoyl DE(DEC) more than 1.6 exhibited monotropic cholesteric phases. On the other hand, NHPCs with $DE{\geq}2.4$ and CNHPCs with $DEC{\leq}1.3$ showed monotropic nematic phases. NHPCs with $DE{\leq}l$, as well as HPC, formed right-handed helices whose optical pitches (${{\lambda}_m}'s$) increase with temperature, while all the CHPCs formed left-handed helices whose ${{\lambda}_m}'s$ decrease with temperature. In contrast with these derivatives, NHPCs with $1.4{\leq}DE{\leq}1.7$ and CNHPCs with $DEC{\geq}1.6$ did not display reflection colors over the full cholesteric range, suggesting that the helical twisting power of the cellulose chain and the cholesteryl group highly depends on the chemical structure and DE of mesogenic group.

• BMB Reports
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• v.42 no.9
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• pp.605-610
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• 2009

Plasma high-density lipoprotein cholesterol (HDL-C) levels are inversely correlated with the risk of cardiovascular disease, and are known to increase with repetitive exercise. In the current study, HDL fractions from athletes' sera were isolated and compared as a function of the type of sport (runners [n = 10], throwers [n = 10], wrestlers [n = 10], and weight lifters [n = 8]), and as an age- and gender-matched reference group (n = 14). Among athletes, HDL from runners had the strongest antioxidant activity. Immunodetection showed that runners and wrestlers had the highest levels of apoA-I and lowest levels of apoA-II in their HDL. Electron microscopy also revealed that HDL2 of runners and wrestlers were the largest in size. In conclusion, although all athlete groups had significantly better serum lipid/lipoprotein profiles than the reference group, runners and wrestlers had the most desirable lipoprotein function and structure, including antioxidant activity, HDL-associated enzyme activities and increased particle size.

• Journal of Environmental Science International
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• v.21 no.7
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• pp.875-881
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• 2012

This study was performed to observe the effects of the feeding physiological activity substance in Cordyceps militaris hot-water extract intake on the improvement of lipid components and metabolic enzyme activities in the serum of dietary hyperlipidemic rats (SD strain, male) fed the experimental diets for 5 weeks. The concentrations of cholesterol (total cholesterol, ${\beta}$-lipoprotein, LDL-cholesterol, free cholesterol and cholesteryl ester), atherosclerotic index, triglyceride (TG), phospholipid (PL) and blood glucose in sera were remarkably lower in the Cordyceps militaris extract intake group than in the hyperlipidemic rats. In the ratio of HDL-cholesterol concentration was higher percentage in the Cordyceps militaris extract intake group than in the hyperlipidemic rats. The activities aminotransferase (AST, ALT) in sera were rather lower in the Cordyceps militaris extract administration than in the hyperlipidemic rats. From the above research, Cordyceps militaris extract were effective on the improvement of the lipid compositions in sera of dietary hyperlipidemic rats.

• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.93-97
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• 2002

Poly(ethylene glycol)-phosphatidylethanolamine conjugate (PEG-PE) has been used in preparing longcirculating liposomes. As a substitute for PEG-PE which can also be used in the long-circulating liposome formualtions, but can be prepared more readily with a lower cost, PEG-Phe-Chol was synthesized from PEG, phenylalanine, and cholesterol. The addition of the PEG derivative to distearoylphosphatidylcholine (DSPC) led to the formation of mixed micelles as well as liposomes when the derivative content was 10 mol% or greater. On the other hand, the addition of just 5 mol% PEG-Phe-Chol to dioleoylphosphatidylethanolamine (DOPE) generated mixed micelles as well as liposomes, but the formation of mixed micelles was completely inhibited by the addition of cholesterol. The leakage of entrapped calcein out of DOPE/cholesterol (7/3) liposomes containing 5 mol% PEG-Phe-Chol was about 45% during the incubation time for 24 h in 50% rabbit plasma, which was similar to that of the same liposomes containing 5 mol% PEG-dipalmitoylphosphatidylethanolamine (DPPE) under the identical conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.04a
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• pp.181-184
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• 2000

A new photo-alignment material, copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy) chalcone-chalconemethacryl) was synthesized and the electro-optical (EO) characteristics for the photo-aligned vertically aligned (VA)-LC display (LCD) were investigated. The monodomain alignment of the NLC for the photo-aligned VA-LCD by linearly polarized UV exposure on the photo-dimerized copoly (PM4Ch-ChMA) surfaces was observed. Excellent voltage-transmittance characteristics for the photo-aligned VA-LCD by UV exposure for 1 min. on the copoly (PM4Ch-ChMA) surfaces were achieved. The response time of the photo-aligned VA-LCD by UV exposure on for 1 min. the copoly (PM4Ch-ChMA) surfaces was about 39.3 ms. The response time for the photo-aligned VA-LCD decreased with increasing UV exposure time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.555-560
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• 1994

In order to observe the effects of the fees mixed with the lard and two vegetable seed oils on the fatty acid compositions of liver and brain tissue, the oils mixed with 2.5% lard and various levels of perilla oil and evening primrose oil were administered to the male rats of the Sprague-Dawley for 4 weeks . In the fatty acid composition of liver lipid, saturated fatty acid (SFA) contents were rich in the phopholiipide and cholesteryl ester fraction. Monounsaturated fatty acid (MUFA) contents were rich in the triglyceride fraction and polyunsaturated fatty acid (PUFA) contents were rich in the phospholipid fraction. In the fatty acid composition of liver lipid fractions, according as the contents of mixed perilla oil decreased and the contents of mixed evening primrose oil increased , n -3 PUFA contents tended to decrease and n-6 PUFA contents tended to increase. Fatty acid composition of liver lipid fractions were influenced from the fatty acid composition of the test lipids. In the fatty acid composition of brain phospholipd, PUFA contents (40%) were rich and according as the contents of mixed evening primrose oil increased, the ratio on n-3/n-6 PUFA and eicosapentaenoid acid (EPA) /arachidonic acid (AA) tended to slightly decrease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.5
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• pp.811-815
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• 1994

In this study the quantity and the ratio of saturated and unsaturated fatty acids were investigated with using gas chromatography after non-polar lipid of the flint corn in the growing period was extracted with the solution of chloroform : methanol (2 : 1) and then separated by the SACC method. Neutral lipid was separated into monoglyceride(MG), 1, 3-diglyceride (1, 3-DG) , free fatty acid (FFA) , triglyceride (TG), cholesteryl ester (CE). Fatty acid of each spot was mainly composed of linoleic , oleic and palmitic acids. Lonolieic acid decreased in MG(54.5-51.4%), CE(31.3-28.9%) but increased ini TG(57.2-63.8%) during growth process. Olec acid increased in MG(25.7-29.3%), 1, 3-DG(24.7-28.9%), CE(16.7-19.9%) but decreased in TG28.6-23.1%). Palmitic acid decreased in MG(12.8-11.5%), FFA(25.7-24.1%), TG(10.4-9.3%) but increased in CE(26.4-31.5%) during a growth process. The ratio of unsaturated to saturated fatty acid in TG(7.01-7.84%) was higher in five spots of neutral lipid and in 1, 3-DG(4.61-4.16%) decreased growth process but increased in MG(5.06-5.60%), TG(7.01-7.84%).

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1211-1216
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• 1998

The study was conducted to investigate the effect of cholesterol and fiber on serum lipid metabolism in rats. Male Sprague Dawley rats were administrated 1% cholesterol and 0.25% sodium cholate to induce hypercholesterolemia and were fed on diet containing three concentrations(0%, 5%, 10%) of cellulose and pectin, respectively. The rats were sacrified after 5 weeks of feeding periods. Serum triglyceride concentration was significantly decreased in proportion to level of fiber. Phospholipid concentration was more decreased in 10% fiber groups than 5% fiber groups but did not show any difference by fiber types. Free cholesterol and cholesteryl ester concentrations in serum were significantly decreased by fiber supplement and pectin was more effective than cellulose in cholesterol lowering effect. Whereas HDL cholesterol concentration and HDL C/TC were increased in proportion to level of fiber and the effect of pectin was not more significant than that of cellulose. Serum chylomicron cholesterol concentration also showed significant decrease by pectin supplement and LDL , VLDL cholesterol concentrations were more significantly decreased in 10% fiber groups than those of 5% fiber groups. The results indicate that 10% pectin may have beneficial roles in hypercholesterolemia.

• The Korean Journal of Mycology
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• v.13 no.4
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• pp.243-247
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• 1985

Experiments were conducted to study effects of steroidal carbamate derivatives upon mycelial growth and aflatoxin production by Aspergillus flavus ATCC 15517. The basal medium was supplemented with various concentrations of these compounds and inoculated with spores. The developing cultures were incubated for 11 days at $28^{\circ}C$ without agitation. Aflatoxins were extracted with chloroform, separated by thin layer chromatography, and quantitated by ultraviolet spectrophotometry. At a concentration of 50 mg per 30 ml of medium., stigmasteryl-N-(2-chloroethyl) carbamate, cholesteryl- N - (2-chloroethyl) carbamate, $5{\alpha}-cholestan-3-one-oximino-N-(2-chloroethyl)$ carbamate and ${\beta}-sitosteryl-N-(2-chloroethyl)$ carbamate were the most effective in reducing aflatoxin production by Aspergillus flavus. However, cholest-4-ene-3-one-oximino-N-(2-chloroethyl) carbamate, at a concentration of 100 mg per 30 ml, significantly decreased aflatoxin production. There was no significant inhibition of mycelial growth by the addition of the various concentrations of these compounds.