• Journal of the Korean Chemical Society
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• v.13 no.1
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• pp.83-88
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• 1969

By the three-step synthesis of alkyltropolone from five-membered cyclopentadiene, as described in Part Ⅰ, methyltropolone has been prepared. From the hydrolysis product of dichloroketene-methylcyclopentadiene cycloadduct, ${\beta}$-(Ⅰ) and ${\gamma}$-methyltropolone (Ⅱ) were separated, with the first predominating, by means of repeated fractional recrystallization and fractional vacuum sublimation. The total yield of these methyltropolones in the hydrolysis step was about 40%. Comparison of this result with those obtained in part Ⅰ revealed the following order as the relative readiness of their preparation: tropolone > methyltropolone > ethyltropolone. The reason for formation of the isomeric (Ⅱ) was discussed by an interpretation of NMR spectrum of cycloadduct in the unsaturation and methylgroup region.

• Journal of the Korean Chemical Society
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• v.37 no.1
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• pp.68-75
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• 1993

Various biological activities (enzyme inhibitory potency, lipoxygenase inhibition, tadpole narcosis, vapor toxicity and heat of vaporization) of molecules are correlated with molecular descriptors. The molecular descriptors used in this works are molecular connectivity index, Wiener distance index and ad hoc descriptor, which can encode information about branching, size, cyclization, unsaturation, hetero atom content and polarizability. It is found that calculated values from multiple regression equations are in a good agreement with experimental data on five biological activities of alcohol, ester and ketone compounds.

• Journal of the Korean Home Economics Association
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• v.18 no.3
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• pp.13-19
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• 1980

To study the rancidity of dried file fish oil by Oxidation during the storage period, general properties of the oil and composition of its fatty acids were analysed qumtitatively with gas-chromatography. The results indicated that; 1) The dried file fish oil was involved in drying oil of heigh degree of unsaturation with IV 158., and consisted of higher-fatty acid with SV 190. 2) The composition of the fatty acids were composed of 18 fatty acids involving 6 unknown fatty acids, and polyunsaturated fatty acid with docosapentaenoic acid(20 weight%). 3) Changes of malonaldehyde content during the storage of dried file fish were about 5.0 mg/kg after 10day, 3.4 mg/kg after 40 days.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.513-518
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• 1991

Evidence from recent studies in several laboratories indicates a relationship between type or level of fat in the diet and occurance of tumor at specific sites. The essential fatty acids in fat and degree of their unsaturation are important to determine the influence of a dietary fats on carcinogenesis. Alteration of dietary fat can also change carcinogenesis of cell in several tissues. Dietary fats appear to be important in both initiation and promotion stages of carcinogenesis. Several possible mechanisms have been investigated how dietary fat could affect to carcinogenesis at cellular level. One potential mechanism of dietary fat on carcinogenesis is through modulation of protein kinase C activity in the cell.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.106-112
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• 1994

Six physical properties (molecular weight, heat capacity, side chain weight, side chain volume, standard entropy and partial molar volume) of amino acids, peptides and their derivatives were examined by molecular modeling techniques. The molecular connectivity index, Wiener distance index and ad hoc descriptor are employed as structural parameters to encode information about branching, size, cyclization, unsaturation, heteroatom content and polarizability. This paper examines the correlation of the molecular modeling techique's parameters and the physicochemical properties of amino acids and their derivatives. As a result, calculated values were in agreement with experimental data in the above six physical properties of amino acids, peptides and their derivatives and the molecular connectivity index was superior to the other indices in fitting the calculated data.

• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.149-155
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• 1986

The fatty acid compositions of phospholipids extracted from leaves and leaf mitochondria, which were sampled from several horicultural plants grown under blue color-deficient sunlight (BCDS), were determined and compared with those from plants grown under natural white colored sunlight(WCS). It was found that the mitochondria isolated from plants grown under BCDS contained phospholipid whose degree of unsaturation in unit of number of double bonds per lipid molecule was remarkably higher than that from plants grown under WCS, the relative increment being $8{\sim}49%$. This was significantly larger than the relative increment, $4{\sim}8%$ for total phospholipid extracted from whole leaves grown under BCDS campared to WCS. This observation demonstrated that the blue light effect of sunlight on the chemical property of cellular membranes, as long as it was concerned with fatty acid composition, arose mainly at the mitochondrial membrane. Also observing that the degree of unsaturation of mitochondrial phospholipid was much lower than that of total phospholipid, it was interpreted that this was the consequence of rather active oxidative destruction of lipid-fatty acid components occuring in mitochondrial membrane by the reactive oxygen species, especially superoxide($O_2-$), which was known to be produced in mitochondrial inner membrane through the side reactions of the respiratory electron transport chain and also probably through the photosensitized reaction involving oxygen induced by blue colored light. Thus, it may be tentatively concluded that the extent of photosensitization in mitochondrial membrane could be considerably reduced under BCDS resulting in lowering of the $O_2-$ level in the respirating organelle The possible involvement of photodynamic action in membrane oxidation was also indicated by the fact that the typical fat-soluble antioxidant, ${\alpha}-tocopherol$, was found to be contained on a higher level in leaves under BCDS than those under WCS.

• Journal of Bio-Environment Control
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• v.4 no.2
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• pp.136-143
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• 1995

Using a PEG- dextran two phase partition method, plasma and intracellular membrane separated from microsomal membrane of canola (Brassica napus) leaves have been fractionated by centrifugation. $K^{+}$- ATPase specific activity in the plasma membrane (U$_2$ phase) of plants grown at $25^{\circ}C$ and 1$0^{\circ}C$ were 6.6 and 4.6 times, respectively that of the microsomal membrane. Plasma membrane had a lower cytochrome- c- oxidase specific activity than the microsomal membrane or intracellular membrane, while intracellular membrane (L$_2$ phase) had a high cytochrome-c- oxidase but little $K^{+}$- ATPase specific activity. The plasma membrane of canola grown at 1$0^{\circ}C$ had higher 18:3 to 18:2 (linolenic to linoleic acid) ratio (29.2% ) and higher degree of unsaturation than that grown at $25^{\circ}C$ The double bond index of plasma membrane from canola grown at 1$0^{\circ}C$ increased by 8.9% relative to canola grown at $25^{\circ}C$. Similar, intracellular membrane increased by 19.7% at 1$0^{\circ}C$. Canola grown at 1$0^{\circ}C$ was lower in chlorophyll contents (17.3%) than that grown at $25^{\circ}C$. These changes in fatty acid unsaturation were attributable largely to change in Cl8 fatty acid, with major changes occurring in linolenic acid (18 :3) which might have a physiological role of membrane to adaptation on low temperature.ure.

• Journal of Nutrition and Health
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• v.10 no.2
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• pp.18-26
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• 1977

Among animals, the rabbit is known to be affected most sensitively by dietary changes and to be most susceptible to atherosclerosis. The exact reason is still unknown as to whether the primary cause is intrinsic (tissue itself) or extrinsic such as a blood factor which could be influenced by various dietary means. It is of utmost importance to check the nutritional quality of rabbit meat before it is accepted and adapted as a daily food item. To evaluate nutritional quality of rabbit meat, studies on various aspects of lipid components were carried out in comparison with other animal meats such as beef, pork and chicken also included in the study was the question whether the cooking and storage conditions influence the composition of fatty acids and cholesterol level. Some results and findings are listed below: 1. The content of linoleic acid (18 : 2), one of the essential fatty acids, was much higher in rabbit meat compared to the other meats. The Percentages of this Polyunsaturated fatty acids, was much higher in rabbit meat compared to the other meats. The percentages of this polyunsaturated fatty acid in terms of total fatty acids were $37.3{\pm}3.7$, 5.9, 14.5, and 21.9% for rabbit, beef, pork, and chicken respectively. The degree of unsaturation was high not only in meat but also in liver and adipose tissue of rabbit. The values of iodine number, the indication of degree of unsaturation, were known to be $102{\sim}107$, $32{\sim}47$, $46{\sim}67$, and $55{\sim}77$ for rabbit, beef, pork, and chicken respectively. Such a high proportion of this polyunsaturated fatty acid contained in rabbit meat could be harmful due to their Peroxidation effect. 2. A small amount of lower (short chain) fatty acids was isolated from rabbit tussues, which were not observed in other animal's tissues. The significance of this small amount of short chain fatty acids contained in rabbit meat remained an open question. 3. The concentration of total cholesterol in rabbit meat was similar to that of otherr but the content of esterified cholesterol was higher in rabbit meat. This was probably due to the perference of cholesterol to esterify with unsaturated fatty acids. By roasting the percentage of Polyunsaturated fatty acids was decreased while saturated palmitic acid was proportionally increased. 4 The composition of fatty acids were affected more by dry heat than moist heat. More research should be pursued to improve methods of preservation and storage to prevent possible peroxidation and rancidity problems of rabbit meat. In the meantime, the public should be informed to eat fresh rabbit meat and not to store it for a long period of time. This study was supported by the Ministry of Science and Technology in Korea.

• Journal of Nutrition and Health
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• v.31 no.5
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• pp.906-913
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• 1998

This study an analyzes the effects of the P/S ratio of dietary lipids and antioxidant vitamin supplements on serum lipids level and fatty acid profile, the degree of lipid peroxidation, and the antioxidant enzyme activities in the liver of rats treated with 7,12-dimethylbenz($\alpha$) anthracene(DMBA). P/S ratio of dietary lipids was made into 0.5, 1 and 2 by mixing palm oil, soybean oil, sesame oil and perilla oil at 10%(w/w) fat level and n-6/n-3 ratio was fixed to 4. Antioxidant vitamin of $\alpha$-tocopherol or $\beta$-carotene was supplemented in addition to vitamin mixture which was given at 1 % of the standard diet. female Sprague-Dawley strain rats, about 60 days old, were divided into three groups(LP : low P/S ratio(0.5), MP : medium P/S ratio (1.0), HP , high P/S ratio(2.0)) and each group was sub-divided into three groups(S ; standard, T ; tocopherol supplemented, C : carotene supplemented): Two weeks after feeding experimental diets, all groups were treated with a single dose of DMBA(2mg/100g BW) by gastric intubation and fed experimental diet for 9 week. The results were as follows ; 1) Serum total cholesterol(TC) level was not significantly influenced by diet but tended to be lower in HP groups compared to LP and MP groups. Triglyceride level was the highest in LP groups and the lowest in $\alpha$-tocopherol supplemented groups. 2) Thiobarbituric acid reactive substance(TBARS) level, representing lipid peroxidation in hepatic microsome, tended to be increased as the unsaturation of dietary lipids increases. $\alpha$-Tocopherol supplement significantly decreased TBARS level. 3) The activities of superoxide dismutase(SOD) and glutathione peroxidase(GSHPx) in hepatic cytosol showed the tendency to be high with increasing P/S ratio of dietary lipids. SOD activity was not significantly influenced by antioxidant vitamin, but GSHPx activity was significantly increased in $\alpha$-tocopherol supplemented groups. In summary, high polyunsaturated fat diet was effective on reducing the serum level of total cholesterol and triglyceride, while it increased unsaturation and peroxidizability of serum fatty acid. With increasing P/S ratio of dietary lipids, lipid peroxidation was increased in the liver and antioxidant enzyme system was induced to inhibit lipid peroxidation against oxidative damage. $\alpha$-Tocopherol supplement was effective in lowering lipid peoxidation, but $\beta$-carotene supplement did not exhibit antioxidant effect. (Korean J Nutrition 31(5) 906~913, 1998)

• Journal of Nutrition and Health
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• v.34 no.6
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• pp.626-636
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• 2001

To compare the effect of three kinds of n-3 fatty acids-eicosapentaenoic acid(EPA), docosahexaenoic acid(DHA) and perilla oil (PO)-on serum and liver lipid levels and fatty acid composition of liver phospholipid(PL) at low fat level(5%, w/w), 4-weeks old Sprague-Dawley rats were fed with one of five different oil diets for 4 weeks. Beef tallow(BT) and corn oil(CO) was used as control for sturated or n-6 fatty acid respectively. Se겨m concentrations of cholesterol(TC) and phospholipid(PL) were lower in PO DHA and EPA groups than in BT and CO groups. HDL-cholesterol levels were higher in CO and PO groups than in EPA, DHA and BT groups. Liver PL concentrations were higher in DHA and EPA groups than in CO, PO and BT groups, but liver TC and heal PL and TC concentrations did not show any significant difference among groups. Hepatic fatty acid composition of phosphatidylcholine (PC) and phosphatidylethanolamine (PE), two major phospholipids in liver, reflected their dietary fatty acid composition. In PC and PE, total percentage own-6 series was higher in CO group than in any other groups, and that own-3 series was higher in DHA and PO groups than in EPA, CO and BT groups. Moreover, the ratio of 20 : 4/18 : 2 was lower in PO and DHA groups than in EPA, CO and BT groups. On the contrary, the percentage of C22 : 6 was lower in EPA, CO and BT groups than in PO and DHA groups. These results revealed that n-3 series(EPA, DHA and PO) were more effective in lowering um lipids than n-6 fatty acids or saturated fatty acid. Based on the results of fatty acid composition of hepatic phospholipid, we suggest that the dietary effect of PO and DHA on antiatherogenic characteristics seems to be similar extent. In addition, the effect of EPA might not be significantly different from that of BT or CO in the view of eicosanoids production from the precursor fatty acid. These difference of hepatic fatty acid composition might come from other characteristics of dietary oil as well as the type of unsaturation, not from the carbon chain length or the degree of unsaturation of n-3 fatty acid.