• Journal of Nutrition and Health
• /
• v.29 no.5
• /
• pp.472-479
• /
• 1996

To investigate the effect of dietary lipids and stress on brain catecholamine and serotonin concentration, sixty three weanling male Sprague-Dawley rats(mean body weight$\pm$SD : 171$\pm$3g) were fed a diet containing fish oil, soybean oil or beef tallow and than, each was exposed to three different types of stress, isolated, grouped or cold, respectively. Cold stress seemed to be most severe and living together in a large cage with some playing equipments is more stressful than living alone in a classical small cage evidenced by plasma corticosterone level. Average food intake and body weight gain were not significantly different among exprimental groups. In adrenal catecholamines, norepinephrine was significantly affected by diet and stress and dopamine was by stress. Norepinephrine concentration of the fish oil group was lowest among diet groups. Adrenal epinephrine, however, was not. It was also shown than the cold stress significantly increased the brain norepinephrine concentration. The cold stress significantly induced higher content of brain serotonin than the grouped stress. However, the concentratin of 5-hydroxyindoleacetic acid(5-HIAA), the metabolite of serotonin, was not significantly different among groups. Therefore, this results suggest that stress affects sympathetic neuronal activity, and fish oil might lighten the burden of stress.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.32 no.6
• /
• pp.913-920
• /
• 2003

Soybean sauce fermented with soybean and wheat, has been a major condiment of Korean diets from centuries ago. Melanoidin, a brown pigment generally found in various food systems, is a final product produced in amino-carbonyl reaction during soybean sauce processing. Antioxidative activities of soybean sauce and melanoidin were investigated in vitro system using linoleic acid emulsion. Soybean sauce and glucose-lysine model melanoidin showed the stronger antioxidative effect than control by ferric thiocyanate and conjugated diene assays. In addition, DPPH radical scavenging effect of soybean sauce was higher than melanoidin, which was ascribed to soluble peptide and low molecular protein existing in soybean sauce. To ascertain antioxidative effect of dietary soybean sauce and melanoidin in vivo, the male Wister rats were fed 10% soybean sauce or 10% glucose-lysine model melanoidin with corn oil or fish oil for 5 weeks. Fatty acid compositions in liver and plasma were influenced by oil source. Therefore, EPA and DHA contents of fish oil group were higher than those of corn oil group. When the inhibitory effect of soybean sauce and melanoidin on lipid peroxidation using TBARS methods was measured, fish oil group (FC) showed higher malondialdehyde (MDA) content than corn oil group (CC). However, supplementation of soybean sauce and melanoidin to fish oil group attenuated MDA formation. In the levels of phosphatidyl choline hydroperoxide (PCOOH) in liver and plasma by CL (chemiluminescence)-HPLC method, PCOOH in FC group was significantly higher than that of CC group both in liver and plasma. Supplementation of soybean sauce to fish oil groups significantly inhibited the formation of PCOOH in plasma and liver, while melanoidin suppressed hepatic PCOOH formation. Based on these results, it can be suggested that soybean sauce possesses stronger antioxidative potential than melanoidin.

• Food Science and Preservation
• /
• v.15 no.3
• /
• pp.437-444
• /
• 2008

Structured lipids(SLs) were synthesized by enzymatic interesterification with DHA-enriched fish oil(containing 27% docosahexaenoic acid) and soybean oil in the hatch-type reactor. The interesterification was performed for 24 hr at $55^{\circ}C$ and TLIM(immobilized lipase from Thermonyces lanuginosa, 10% by weight of total substrates) was mixed with 180 rpm of shaking. The fish oil and soybean oil were interesterifed with several weight ratio(fish oil : soybean oil, 2:8, 3:7, 4:6, 5:5, w:w), Reverse-phase high performance liquid chromatography with an evaporative light-scattering detector separated the triglyceride species of SLs. The products contained the newly synthesized peaks. Especially, one of peaks was distinctively increased with the increasing weight ratio from 2:8 to 5:5 while the peak of trilinolein (LLL) decreased vice versa. The effect of antioxidants such as catechin, BHT(Butylated hydroxytoluene), and their combinations on the oxidative stability in SL were investigated. Oxidative stability was carried out under oven test at $60^{\circ}C$ over 72 hr thereafter SLs were analyzed for total fatty acid content, rancimat, peroxide value, electronic nose and TBARS value. Among all combinations of antioxidant, the highest stability was obtained from 200 ppm of catechin. Besides, total tocopherol ($\alpha$, $\gamma$, and $\delta$-tocopherol), iodine and saponification value were analyzed in which iodine and saponification value of SLs were 151.19 and 182.35.

• Journal of Aquaculture
• /
• v.22 no.1
• /
• pp.63-67
• /
• 2009

In order to establish optimum anesthesia concentration, we tested the efficacy of clove oil at five different concentrations in large sized (mean SL $17.1{\pm}2.21\;cm$) and small sized (mean SL $0.6{\pm}0.06\;cm$) dark-banded rockfish Sebastes inermis. Optimal anesthesia concentration for dark-banded rockfish was $150\;mgL^{-1}$ in both large and small sized fish. In general, fish exposed to higher anesthetic doses were rapidly induced but took longer to recover (P<0.05). Recovery time of small sized fish was longer than large sized fish in lower concentrations, while recovery time of large sized fish was longer than small sized fish in higher concentration (P<0.05). Using the established optimum aesthetic concentration, we evaluated the physiological response of dark-banded rockfish to clove oil by measuring plasma cortisol and glucose levels. Following administration of $150\;mgL^{-1}$ clove oil at $20^{\circ}C$ (optimum breeding temperature), plasma cortisol level was highest ($42.2{\pm}11.318{\mu}g/dL$) after 0 hour, while plasma glucose level was highest ($52.5{\pm}10.61\;mg/dL$) after 1 hour. Plasma cortisol and glucose concentrations required 6 and 2 hours, respectively, to return to pre-exposure levels.

• Food Science and Biotechnology
• /
• v.16 no.6
• /
• pp.999-1005
• /
• 2007

An oil-in-water (O/W) emulsion [20 wt% com oil, 0.5-6.0 wt% fish gelatin (FG), pH 3.0] was produced by high pressure homogenization, and the influence of pH, protein concentration, and homogenization condition on the formation of FG-stabilized emulsions was assessed by measuring particle size distribution, electrical charge, creaming stability, microstructure, and free FG concentration in the emulsions. Optical microscopy indicated that there were some large droplets ($d>10\;{\mu}m$) in all FG-emulsions, nevertheless, the amount of large droplets tended to decrease with increasing FG concentration. More than 90% of FG was present free in the continuous phase of the emulsions. To facilitate droplet disruption and prevent droplet coalescence within the homogenizer, homogenization time was adjusted in O/W emulsions stabilized by 2.0 or 4.0 wt% FG. However, the increase in the number of pass rather promoted droplet coalescence. This study has shown that the FG may have some limited use as a protein emulsifier in O/W emulsions.

• Preventive Nutrition and Food Science
• /
• v.13 no.1
• /
• pp.7-11
• /
• 2008

To improve the utilization of fish processing by-products, fish oils were extracted from hoki, yellowfin sole, mackerel, and horse mackerel, and their compositions were examined. The proximate compositions obtained for these 4 species of by-product revealed they were composed of 68.1$\sim$78.1% moisture, 1.2$\sim$1.6% ash, and 13.8$\sim$18.8% protein. Fish oils extracted from the hoki, yellowfin sole, mackerel, and horse mackerel were 5.5, 9.4, 13.4, and 10.3%, respectively. The total lipids extracted from the by-products of the 4 species were 6.21, 10.43, 12.81 and 10.06%, of which neutral lipids accounted for 77.38, 77.46, 87.21 and 86.79%, respectively. Neutral lipid analysis by TLC showed that triacylglycerol was the major component, while 1,3- and 1,2-diacylglycerols, free fatty acids, free sterols, and sterol esters were present as minor components. The major fatty acids were palmitic acid, stearic acid, and oleic acid. DHA and EPA were contained at levels of 0.2$\sim$4.7% and 3.7$\sim$9.5%, respectively, in the 4 types of fish oil. The fish oils extracted from the dark muscle fish, mackerel and horse mackerel, had greater polyunsaturated fatty acid (PUFA) contents than those of the white muscle fish species, hoki and yellowfin sole.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.49 no.3
• /
• pp.317-322
• /
• 2016

This study was carried out to investigate the effects of various dietary lipid sources on the growth performance, body composition, and fatty acid profiles of juvenile fancy carp (Cyprinus carpio var. koi). Three replicate groups of fish (initial mean body weight, 15.1±0.18 g) were fed one of five experimental diets containing fish oil (SLO), soybean oil (SO), linseed oil (LO), lard (LA), or a mixture of SLO, SO, and LO (Mix) for 8 weeks. Fish fed the LA diet gained less weight than did fish fed the LO diet. The feed efficiency and protein efficiency ratio of fish fed the LA and Mix diets were lower than those of fish fed the SO and LO diets. The body lipid content of fish fed the SO diet was lower than those of the other groups. Whole-body fatty acid compositions reflected the fatty acid compositions of dietary lipid sources. Fish fed the SO diet had high concentrations of linoleic acid and arachidonic acid, whereas fish fed the LO diet were rich in linolenic acid. Fish fed the SLO diet had significantly higher levels of eicosapentaenoic acid and docosahexaenoic acid compared with fish fed the SO, LO, and LA diets. The results of this study suggest that SO or LO could be used as a replacement for SLO in the diets of juvenile fancy carp without any negative effects on growth and feed utilization when the dietary essential fatty acid requirements are satisfied for juvenile fancy carp.

• Journal of Nutrition and Health
• /
• v.23 no.6
• /
• pp.408-417
• /
• 1990

To compare the hypolipidemic effect of n6 linoleic acid n3 $\alpha$-linolenic acid and n3 eicosapentaenoic acid plus docosahexaenoic acid, male Sprague Dawley rats weighing about 450g were fed the experimental diets for 6 weeks which composed of fat at 15%(W/W) level and were different only in dietary PUFA. Dietary fat was corn oil, perilla oil, and fish oil concentrate as a source of n6 linoleic acid, n3 $\alpha$-linolenic acid, and n3 eicosapentaenoic acid+docosahexaenoic acid, respectively. Plasma total Chol and HDL-chol levels were significantly-lower in fish oil group than in corn oil and erilla oil groups. Plasma cholesterol lowering effect of PUFa was in the order of n3 EPA+DHA>n3 $\alpha$-linolenic acid>n6 linoleic acid. Plasma TG was significantly lower in both fish oil and perilla oil groups than in corn oil group. Plasma TG-lowering effect was greater by n3 PUFA (EPA+DHA, $\alpha$-linolenic acid) than by n6 PUFA(linoleic acid). However, there were no significant effects on lipoprotein pattern hemolysis, and the levels of tocopherol and malondialdehyde in plasma and RBC by difference dietary fat with sufficient tocopherol supplement. Liver superoxide dismutase activity was significantly increased in proportion to the degree of fat unsaturation, thereby resulted in the lower level of MDA in fish oil group. In conclusion, fish oil and perilla oil rich in n3 PUFA may have important nutritional applications in the prevention and treatment of atherosclerotic disease.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.20 no.1
• /
• pp.79-87
• /
• 1987

This study was carried out in order to investigate the browning reactions of fish oil-amino acid model system and the properties of browning products. The lysine was added to the hair tail fish and mackerel oil, and incubated at $40^{\circ}C$ for 178 hours. Browning was rapidly developed with the begining of decline in PoV and CoV and a remarkable decrease in such polyunsaturated fatty acids as $C_{20:5},\;C_{22:5},\;C_{22:6}$ compared with the other fatty acids, was resulted. And among the polyenoic acids the role of $C_{22:6}$ was considered to come first as appeared in the test with authentic samples. In the water soluble fraction of the browning products obtained from the fish meat or the lysine added fish oil, some antioxidation activity was detected. But in the liposoluble fraction which covers most of the browning reactions in the fish meat, little antioxidation activity was detected. And all of the browning products provided in this experiment shelved very low reducing activity.

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