• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.436-445
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• 1986

As the second part of the studies on the utilization of polyunsaturated lipids in sardine oil as nutritional or medical supplement, the conditions of lipid extration and concentration, refining, and storage stability of EPA-condensed sardine oil were investigated. In extraction of lipids, solvent ratios of chloroform-methanol mixture(2:1 v/v) affected the final content of unsaturated lipid in extracted oil and recovery. Stepwise solvent fractionation method at various low temperatures was effective to concentrate polyenoic acids like EPA and DHA when acetone or acetone-methanol mixture, added in the ratio of 1:5 (v/v) was applied step by step to different temperatures at 0 to $-35^{\circ}C$. Addition of 1 to $5\%$ (v/v) of water to acetone was also benefit to raise EPA content but that resulted in reducing the yield of condensed oil from $65\%\;to\;28\%$. Concentration rate of polyenoic acids by solvent fractionation in lipid-actone solution (1:5, v/v) at 0 to $-30^{\circ}C$ seemed limited to $5{\sim}8\%$ in fatty acid composition depending on the initial content of those polyenoic acids in the sardine oil. During the extraction, concentration, and alkaline treatment, oxidation was rapidly induced but oxidation products could be thoroughly removed on the process of deceleration and peroxide elimination. To stabilize the reactive polyenoic acid condensed oil during the storage, stuffing nitrogen gas was essential to expel dissolved oxygen in oil or to seal the oil from open air, and the addition of antioxidative agents as BHA and tocopherols were greatly helpful to extend the storage life.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.423-435
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• 1986

As the first part of the studies on utilization of polyunsaturated lipids in red muscled fishes like sardine (Sardinops melanosticta) and mackerel (Scomber japonicus), lipid distribution in body sections, whole body, meat, viscera, skin, and head, lipids, polar and nonpolar, and fatty acid composition of the oils obtained from these body sections, and seasonal variations in fatty acid composition, particularly in the content of polyenoic acids, EPA and DHA, were determined, The content of total lipids was ranged $22.2\%\;to\;27.2\%$ in case of sardine without broad difference between body sections, while in case of mackerel $36.7\%\;to\;38.8\%$ unevenly in skin and head. The lipids of both fish were composed of more than $80\%$ of non-polar lipid and there was not much differences in the fatty acid composition between the lipids, polar and non-polar. The major fatty acids of the lipids were $C_{14:0},\;C_{16:0},\;C_{18:0},\;C_{16:1},\;C_{18:1},\;C_{20:1},\;C_{20:4},\;C_{20:5},\;and\;C_{22:6}$, and these acids, $C_{18:1},\;C_{16:0},\;C_{22:6},\;C_{18:0},\;C_{20:5},\;C_{14:0},\;C_{16:1}$, were in high quantity in order. Seasonal variation in fatty acid composition of sardine oil did not show any great variety between sections. There was a tendency in general that saturated and monoenoic acids began to decrease in winter and showed the minimum in April; hereafter get to increase again, while polyenoic acids showed the maximum in April. Both $C_{20:5}\;and\;C_{22:6}$ acids were high in the season of April to July. Variation in fatty acid content was in a width of $8\%$ for saturated, $5\%$ for monoenoic, and $12\%$ for polyenoic acid. $C_{20:5}\;and\;C_{22:6}$ acid were varied in $9.4\%\;and\;9.8\%$, respectively. In case of mackerel oil, seasonal variation tended same as in sardine oil except the fact that the saturated and monoenoic acid decreased to the minimum in the term of April to July in which the polyenoic acid content was also higher marking $27.3\%\;to\;36.1\%$ in average. Fatty acid variation was in a range of $6.3\%$ for saturated, $8.3\%$ for monoenoic, and $13.8\%$ for polyenoic acid but variation of $C_{20:5}\;and\;C_{22:6}$ acid was 4, $3\%$ and 3, $4\%$ respectively. When fresh sardine was stored for 10 days at $5^{\circ}C$, oxidation was rapidly initialed and consequently resulted in fast loss of $C_{20:5}\;and\;C_{22:6}$ acids. It is concluded from the results that the catch of sardine and mackerel in the season of April to June would be adequate for the preparation of polyunsaturated lipid condenced oil in regard to sectional lipid distribution and its variation in seasons.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.603-608
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• 1998

Lipid oxidation in ascidian was studied when fresh, deshelled and sliced meats were fermented for 50 days at 5$\pm$2$^{\circ}C$ with 8%(w/w) salt and 0.1% papain. Antioxidative effects of butylated hydroxytoluene(BHT) and carotenoid extracts from ascidian tunic on lipid oxidation and oxidationrelated discoloration of ascidian meat during fermentation were investigated. Changes in peroxide value, carbonyl value, thiobarbituric acid value, fatty acids composition, the loss of total carotenoid and sensory evaluation were determined to assess the rancidity. Peroxide and carbonyl values in BHT and carotenoid extract treatments increased less than those of the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control during fermentation. TBA value increased until 30 days, hereafter tended to decrease a little in the control but it increased slowly until 40 days in cases of 0.02% BHT or 0.02% BHT with 0.05% carotenoid added. Fatty acids of fresh ascidian composed of polyenoic acid, saturated acid and monoenoic acid of 51.5%, 28.1% and 20.7%, respectively. Saturated fatty acids(C16:0, C14:0, C18:0) and monoenoic acids(C18:1, C16:1) increased while polyenoic acids(C20:5, C22:6) decreased during fermentation. Carotenoid was markedly degraded and discolored in the control during fermentation. But 0.02% BHT and 0.05% carotenoid treatments had bright color like fresh meat during 40 days. The results of sensory evaluation during the fermentation also convinced the retard of discoloration by the addition of BHT and carotenoid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.5
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• pp.387-394
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• 1990

The effect of lysine or methionine addition on the lipid oxidation and protein properties in casein-fish oil model system during the storage of 21 days at 37$^{\circ}C$ was studied. The peroxide and TBA values were increased markedly and the amino acids addition to the system caused to reduce the extent of lipid oxidation in comparison with that of casein-fish oil system which was a control group. Significant changes in fatty acid composition of each group were observed. Polyenoic acid contents were drastically decreased during the storage in the groups with and without the amino acids additions, . And also significant losses of several amino acids were occurred with the reduction of solubility and digestibility of casein during the storage. However no different effects were observed in both additionsof lysine and methionine to the system.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.416-419
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• 1999

To evaluate lipid oxidation in dried shellfish during storage, brown pigment formation and composition of fatty acid were determined. Levels of brown pigment formation occurred at $25^{\circ}C$ were higher than those occurred at $4^{\circ}C$ throughout the storage period. Especially, the formation content of lipophilic brown pigment was 9$\~$10 times higher than that of hydrophilic brown pigment in all samples. Fatty acid composition of total lipid (TL) in fresh sea mussel and baby clam were $34.21\%$ and $32.83\%$ in saturated fatty acid, $19.50\%$ and $20,83\%$ in monoenoic acid, and $46.29\%$ and $46.79\%$ in polyenoic acid, respectively. The prominent fatty acids were 16:0, 16:1 and 20:5 in TL of the both samples. During storage, the contents of saturated fatty acid and monoenoic acid were slightly increased but that of polyenoic acid was decreased. In sea mussel, the content of polyenoic acid was higher in phospholipid (PL) than in neutral lipid (NL), while saturated fatty acid and monoenoic acid content were higher in the latter. The ratios of polyenoic acid/saturated fatty acid (P/S) in NL was similar in all samples. But the ratio of P/S in PL was higher in baby clam ($1.81\%$) than that in sea mussel($1.42\%$).

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.83-89
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• 1987

The crude lipid contents of dried sea food products varied remarkably from 1.2 to 29.9% for dried fish products, from 2.8 to 12.3％ for dried mollusk ones, and from 0.1 to 2.3％ for dried seaweed ones. In fatty acid composition of dried fish products, the saturated acid was the most predominant component for dried anchovies, hair tail, Kstsuobushi, the monoenoic acid was the most predominant one for dried yellow corvenia, flat head, common carp, sea eel and conger eel. And the polyenoic acid was the most abundant one for dried cod. Allaska pollack, flounder, sole fish, ray, smelt and sardine. The major fatty acids of these dried fish products were 16:0, 16:1, 18:0, 18:1, 20:5 and 22:6. Fatty acid composition of dried mollusk products were mainly consisted of polyenoic acid, and followed by saturated acid, monoenoic aced. The major fatty acids of these products were similiar to those of dried fish products. And in case of dried seaweed products, saturated acid such as 14:0, 16:0 was the most predominant component, while polyenoic acid was abundant one in dried laver and sea mustard. The main fatty acids of dried seaweed products were 14:0, 16:0, 18:1, 20:1, 20:4, and 20:5. Judging from the results, dried sea food products were abundant of the highly unsaturated fatty acids in spite of the drying processing and storage.

• Journal of the Korean Applied Science and Technology
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• v.9 no.1
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• pp.25-30
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• 1992

The needles and pollen of Pinus densiflora and Pinus koraiensis were studied for their lipid contents and fatty acid composition. The total lipid contents in needles of Pinus densiflora and Pinus koraiensis were 5.0 and 4.5%, whereas in pollen of Pinus densiflora and Pinus koraiensis 3.5 and 5.6%, respectively. Twenty-four fatty acids ranged from lauric acid to docosahexaenoic acid(22:6${\omega}$3) were identified in the needle lipids. In needles, linolenic acid and palmitic acid were the major fatty acids. The needles of Pinus densiflora showed higher proportions of docosahexaenoic acid and 5-olefinic nonmethylene-interrupted polyenoic acids than those in the Pinus koraiensis. Twenty fatty acids ranged from myristic acid to lignoceric acid were identified in the pollen lipids. Linoleic acid was the major fatty acid in the pollen followed by oleic and palmitic acid. The fatty acid profile of pollen of Pinus densiflora was similar to those of the Pinus koraiensis pollen lipids.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.4
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• pp.297-308
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• 1985

Differences in lipid composition including fatty acid, lipid class, sterol and especially carotenoid between fleshes of wild and cultured prawn, Penaeus japonicus, were studied. Total lipids were extracted from the flesh during the spawning period and fractionated into two lipid classes of polar and nonpolar lipids by silicic acid column chromatography. The fatty acid composition of each lipid classes, total lipid (TL), nonpolar lipid (NL) and polar lipid (PL) were analyzed by gas liquid chromatography. The sterol and carotenoid composition of total lipids were determined by using thin layer chromatography, gas liquid chromatography and column chromatography using MgO-celite 545 and silicic acid-celite 545 as an absorbent, and by UV spectrophotometry. Total lipid contents of both fleshes from the wild and cultured prawn were about $2.0\%$ on average, but the content of the unsaponifiable matters in the cultured prawn (about $16.2\%$ in total lipid) showed a little higher than that of the wild prawn (about $13.9\%$ in total lipid) and the ratio of NL to PL in total lipid was 1:1.7. In the fatty acid composition of TL, the contents of $Cl_{16:0}\;and\;C_{20:3}$ fatty acids were higher in wild prawn than in cultured prawn, while the contents of $Cl_{18:1}\;and\;C_{20:5}$ fatty acids in cultured prawn were higher than those in wild prawn. The cultured prawn contained higher amounts of monoenoic acids and lower amounts of polyenoic acids than the wild prawn. In the fatty acid composition of NL, the wild prawn showed higher levels in $Cl_{18:0}\;and\;C_{20:1}$ fatty acid contents than the cultured prawn, while the cultured prawn contained much amout of $Cl_{16:0}\;and\;C_{18:1}$ fatty acids. On the other hand, the fatty acid composition of PL showed that $Cl_{16:1}\;and\;C_{17:1}$ fatty acid were higher in the wild prawn than in the cultured prawn, but in $Cl_{16:0}\;and\;C_{18:1}$ fatty acids, the levels were reversed. Consequently, the cultured prawn contained higher amount of monoenoic acids, and similar amounts of saturated acids and polyenoic acids to the wild prawn in NL. And the cultured prawn contained lower amount of monoenoic acids, and similar amounts of saturated acids and polyenoic acids to the wild prawn in PL. In sterol composition of both the wild and cultured prawn, the predominant sterol was cholesterol with the proportion of $78.7{\sim}88.9\%$ to the total sterol. In addition to the cholesterol, the other minor sterols such as 24-methylene cholesterol and sitosterol were detected. Total carotenoid content in flesh of the wild prawn was relatively higher than that of the cultured prawn marking 70 mg/100g of lipid in wild prawn and 40 mg/100 g of lipid in cultured prawn, respectively. The main carotenoids of the both prawns were astaxanthin($54.1{\sim}60.8%$), phoenicoxanthin ($16.5{sim}22.9%$),${\bata}-carotene\;(20.0{\sim}22.0%)$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.1
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• pp.63-68
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• 1987

The results of previous paper(Lee et al, 1987), indicated that the role of polyunsaturated carbonyls from the polar lipid seemed more important than those of the nonpolar lipid in the browning reaction. In this study, the role of phosphoipid in lipid oxidative browning reaction was investigated. In fatty acid composition of hair tail fish, neutral lipid and glycolipid contained the higher percent of saturated and monoenic acids while phospholipid contained more of polyenoic acids. When this fish was dried and stored, polyunsaturated fatty acids of phospholipid and glycolipid more rapidly decreased than that of neutral lipid. The browning was developed more rapidly in phospholipid than in glycolipid and neutral lipid. In the test of phospholipids, the phosphatidylcholine which fractionated by $CHCl_3-MeOH(1:1)$ solution was the largest in quantity, tut the phosphatidylethanolamine which fractionated by $CHCl_3-MeOH(4:1)$ was more active in the development of browning.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.208-212
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• 1997

Total lipid were extracted from the eggs of Fugu xanthopterus and were then resolved into lipid subclasses by silica gel column chromatograpy. The fatty acid composition of total lipid, triacylglycerols, phospholipids and wax esters of these oils were analyzed by gas-liquid chromatography. Proximate percentage of total lipid from the sample was 12.63%. The lipid classes of eggs of Fugu xanthopterus fractionated by silica gel column chromatograpy were 59.37% of triacylglycerols, 15.46% of phospholipids, 6.9% of wax esters. The egg lipid obtained from Fugu xanthopterus was enriched with DHA in every class. In particular, the phospholipid contained the highest level of DHA(19.3%) than the other. The sum of polyenoic acids(27.4%). The fatty alcohols were mainly composed of saturated alcohols such as C16:0 alcohol(62.6%), C14:0(7.9%) and C18:0(5.8%), while the level of polyene alcohols was strikingly low compared with that of saturated alcohols.