• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.67-73
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• 2014

The oil in mackerel muscle was extracted using an environment friendly solvent, supercritical carbon dioxide (SC-$CO_2$) at a semibatch flow extraction process and an n-hexane. The SC-$CO_2$ was maintained at a temperature of $45^{\circ}C$ under pressures ranging from 15 to 25 MPa. The flow rate of $CO_2$ (27 g/min) was constant during the entire 2 h extraction period. The fatty acid composition of the oil was analyzed using gas chromatography (GC). Significant concentrations of eicosapentaenoic acid (EPA) acid and docosahexaenoic acid (DHA) acid were present in the SC-$CO_2$ extracted oil. The oil extracted using SC-$CO_2$ exhibited increased stability compared with n-haxane extracted oil. Particles of mackerel oil together with the biodegradable polymer, polyethylene glycol (PEG) were formed using a gas saturated solution process (PGSS) with SC-$CO_2$ in a thermostatted stirred vessel. Different temperatures ($45-55^{\circ}C$), pressures (15-25 MPa) and a nozzle size $400{\mu}m$ were used for PGSS with a 1 h reaction time. The stability of mackerel oil in the particles did not changed significantly.

• Journal of Nutrition and Health
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• v.21 no.1
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• pp.61-74
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• 1988

Ten college women were divided into 5 groups and treated in randomized block design for 5 weeks with 1 interval between treatments and subjects serving as their own controls. The experimental diets were corn oil diet as a source of n-6 linoleic acid, perilla oil diet as a source of n-3 $\alpha$-linolenic acid, and fish oil diet as a source of n-3 EPA and DHA. Dietary fat was supplied at 30% Cal and modified to give the total amount of saturated fatty acids and monoenoic acids at constant level. There was no significant effect on serum cholesterol level by different PUFA. However, on a gram-for-gram basis, there was a trend that the decrease in serum cholesterol was proportionate to the degree of fat unsaturation. On the other hand, only fish oil diet significantly decreased TG level but no significant effect on the relative proportion of TG in VLDL. The degree of hypotriglyceridemia did not corrleate with the degree of unsaturation. The relative proportion of CE in LDL was reduced by all PUFA diets but significant only by perilla oil diet. The relative amount of apoprotein in LDL was significantly reduced by n-3 PUFA. HDL-Chol content was significantly increased only in fish oil diet but no change in the relative proportion of its chemical components of HDL.

• Journal of Korean Biological Nursing Science
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• v.19 no.3
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• pp.141-150
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• 2017

Purpose: The purpose of this study was to investigate the effects of the Korean Dietary Approaches to Stop Hypertension (DASH) education program on oxidative stress, antioxidant capacity, and serum homocysteine (Hcy) level in elderly Korean women. Methods: This was a quasi-experimental study employing non-equivalent control group pretest-posttest design. The DASH group (n= 27) underwent the DASH education program for 12 weeks, whereas the control group (n= 21) was provided one education session. The survey was conducted before and after the intervention period. Results: In DASH group, monounsaturated fatty acid (MUFA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) intakes significantly increased after the intervention as compared to prior to the intervention. No significant differences were found in the control group. After the intervention, thiobarbituric acid reactive substance (TBARS) and Hcy levels significantly decreased in the DASH group but not in the control group. Conclusion: The DASH education program was effective in reducing oxidative stress and Hcy levels in elderly Korean women.

• Biomolecules & Therapeutics
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• v.10 no.1
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• pp.25-31
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• 2002

This study was carried out to identify the effect of oxidative stress on the pathogenesis of manganese intoxication. Five rats in experimental group were given with $MnCl_2$intraperitoneally for 4 weeks(4 mg/kg once daily 5 days per week) and another five rats for control group were given with normal saline. In experimental group, manganese concentrations increased significantly in nucleus accumbens by 142% (p<0.05), SOD activities increased significantly by 124%(p<0.01), and MDA concentrations increased significantly 148%(p<0.05) compared with control group. Among fatty acids, total n-6 polyunsaturated fatty acids(PU) increased significantly by 231%(p<0.05) compared with control group. Arachidonic acids(AA) increased by 224%(p<0.05), and these increase were composed mostly of n-6 polyunsaturated fatty acids(PUFA). Among n-3 PUFAs except linolenic acids, eicosapentanolc acid(EPA) decreased significantly by 38%(p 0.01) and docosahexanoic acids(DHA) decreased by 30% p<0.05) compared with control group. Our results suggest that the oxygen free radicals produced by manganese may cause compositional changes of fBtty acids in nucleus accumbens of the rat. Characteristics of fatty acids compositional changes by manganese were the decrease of EPAs and DHAs(n-3 PUFAs), and increase of AAs(n-6 PUFAs). These changes with the increase of MDA, suggest that manganese neurotokxcity is caused by lipid perokidation mediated with oxygen free radicals, especially superoxide radicals.

• KSBB Journal
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• v.26 no.6
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• pp.557-560
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• 2011

It has been known that Δ-desaturase (TAD5) in the biosynthetic pathway of long chain polyunsaturated fatty acids of Thraustochytrium aureumis responsible for the conversion of di-homo-${\gamma}$-linolenic acid (C20：4) into arachidonic acid (C20：4). The genetic sequence analysis on TAD5 of Thraustochytrium aureum ATCC34304 used in this study showed that it has two amino acid changes when compared to that of Thraustochytrium aureum TAD5 first reported in 2003. Accordingly, Thraustochytrium aureum ATCC34304 TAD5 was named TAD5_1. TAD5_1-inserted methylotropic Pichia pastoris was prepared and then cultured with a precursor fatty acid, di-homo-${\gamma}$-linolenic acid. GC analysis confirmed that a certain amount of the precursor fatty acid was converted into arachidonic acid. In this study, not only a recombinant Pichia pastoris with the typical activity of ${\Delta}5$-desaturase which plays an essential role in the biosynthesis of LCPUFAs was successfully made but also the preparationpotential of a recombinant Pichia pastoris strain which may synthesize eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) that are important in maintaining and improving human's brain function was proposed.

• 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.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.769-772
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• 2000

Fish oil has abundant highlly unsaturated fatty acids such as EPA and DHA. Therefore, fish oil is very susceptible to peroxidation. Adding any antioxidants to fish oil is acceptable to prevent the peroxidation. However, nontoxic and strong naturally occurring antioxidants for fish oil was not developed. ${\alpha}-tocopherol$ is one of useful natural antioxidants, but it is not good to prevent the fish oil peroxidation. In this study, we examined the development of microencapsulated squid liver oil product to prevent effectively peroxidation of the fish oil. The acceptable materials for encapsuling the squid liver oil were gum arabic and gelatin. The ultimate encapsulation rate of squid liver oil was 45.5%.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.3
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• pp.198-205
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• 2006

This study was designed to investigate the possibility of the use of dried mackerel, which is enriched with docosahexaenoic (22:6n-3, DHA) and eicosapentaenoic (20:5n-3, EPA) acids, as a means of increasing the intake of these n-3 polyunsaturated fatty acids, and to investigate the effect of the consumption of mackerel on tissue triglyceride, cholesterol contents and fatty acid compositions. Twenty male mice were fed on 5% palm oil (control group) and 5% dried mackerel (mackerel group) diets for four weeks. Total triglyceride, cholesterol and LDL-cholesterol levels tended to decrease in serum, heart and kidney of the mackerel group compared to the control group, while HDL-cholesterol levels were increased with the intake of mackerel. In fatty acid compositions of serum and heart, the mackerel group showed increased percentages of n-3 fatty acids, especially DHA and EPA, and decreased percentages of arachidonic (20:4n-6, AA) and docosapentaenoic (22:5n-6, DPAn-6) acids compared to the control group (p<0.05). There was a similar tendency in kidney and adipose tissue but AA levels were not significantly different between the control and mackerel groups. These results indicate that intake of dried mackerel as the n-3 vehicle for increasing tissue n-3 fatty acids may be associated with improvement in lipid metabolism.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.319-328
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• 1997

To develop a beneficial microbial feed for the cultivation of rotifer, Brachionus plicatilis, an aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ was isolated from marine structure at Haeundae beach in Pusan, Korea. Feeding effects of Erythrobacter sp. $S\;\pi-I$ on the growth of rotifer were analyzed comparing to other feeds such as PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. Erythrobacter sp. $S\;\pi-I$ contained more linoleic acid $(C_{18:3\omega3})$ and oleic acid $(C_{18:1\omega9})$ and amino acids than PSB (purple nonsulfur bacteria), Chlorella sp. and baker's yeast. The rotifer fed on Erythrobacter sp. $S\;\pi-I$ showed better effects than those fed on other feeds in the individual growth, size and weight. Also, the rotifer especially contained more eicosapentaenoic acid $(C_{20:5\omega3})$ and docosahexaenoic acid $(C_{22:6\omega3})$ in case of Erythrobacter sp. $S\;\pi-I$ feeding than the other feeds. In case of the feed of PSB and baker's yeast docosahexaenoic acid $(C_{22:6\omega3})$ did not show. In amino acid analysis, the rotifer fed on Erthrobacter sp, $S\;\pi-I$ showed more amino acid content comparing to those fed on other diets. Especially, arginine, isoleucine, histidine, lysine, methionine, phenylalanine, threonine, which are essential amino acid for fish growth, showed high contents. These results suggested that the aerobic photosynthetic bacterium, Erythrobacter sp. $S\;\pi-I$ would be a beneficial microbial teed for the cultivation of rotifer.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.278-289
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• 2021

The rapid aging of society has led to a surge in cognitive dysfunction in the elderly. As there is limited evidence for the development of dementia in medicine, a shift in focus on prevention strategies using bioactive compounds in food is required. This systematic review evaluated the effects of various bioactive compounds on age-associated cognitive decline. The literature was searched for terms related to bioactive compounds in cognitive decline and article selection was limited to clinical randomized controlled trials for a single bioactive compound. We identified 21 studies that evaluated the strength of the evidence. ω-3 fatty acids and vitamin B presented a strong evidence level, whereas vitamin D and E, anserine/carnosine, and chromium were defined as having moderate levels of evidence. ω-3 fatty acids relieved cognitive decline and reduced amyloid β-related protein accumulation. Vitamin B decreased homocysteine levels, which is accompanied by alleviation of cognitive function. In conclusion, ω-3 and vitamin B have the potential to improve age-associated cognitive decline.