• Korean Journal of Mathematics
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• v.22 no.3
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• pp.443-454
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• 2014

In this paper, we give linearization of generalized Fi-bonacci sequences {$g_n$} and {$q_n$}, respectively, defined by Eq.(5) and Eq.(6) below and use this result to give the matrix form of the nth power of a companion matrix of {$g_n$} and {$q_n$}, respectively. Then we re-prove the Cassini's identity for {$g_n$} and {$q_n$}, respectively.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.919-923
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• 1999

The edible portions of saury were cooked by pan frying, deep fat frying, steaming and microwave cooking to compare the compositions of fatty acids in cooked fish with those in raw fish. The total lipid in saury studied varied by each fish but ranged from 21.87% to 30.63%. The distribution of each fatty acid (average) was in order; $C_{22:1}\;(21.75%)>C_{20:1}\;(15.81%)>C_{16:0}\;(11.75%)>C_{22:6}\;(DHA,\;10.61%)>C_{14:0}\;(7.04%)>C_{20:5}\;(EPA,\;5.13%)$. The average ratio of PUFA (polyunsaturated fatty acids)/SFA (saturated fatty acids) in saury fillet was 1.07 and that of n-3/n-6 was 9.15, which showed saury might be a good source for PUFA including n-3 fatty acids. Comparing the effects of cooking on EPA and DHA, two of the most important n-3 PUFA, the decreasing rate of EPA were 6.98% (pan frying), 26.93% (deep fat frying), 1.16% (steaming) and 15.12% (microwave cooking), respectively. The decreasing rate of DHA ware 4.30% (pan frying), 15.99% (deep fat frying), 3.26% (steaming) and 9.56% (microwave cooking). This study showed that both EPA and DHA were reduced by steaming least, and pan frying, microwave cooking, deep fat frying most, in order.

• Journal of Aquaculture
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• v.6 no.3
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• pp.199-211
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• 1993

In order to elucidate the effect of dietary n-3 highly unsaturated fatty acids (n-3HUFA) on the changes of body weight and chemical compositions in the Korean rockfish during starvation, the fish were not fed for 9 weeks after fed different levels $(0\~1.5\%)$ of n-3 HUFA for 10 weeks. The higher level of n-3HUF A was contained in the diets, the slower body weight loss was resulted (P< 0.05). The decreasing rates of the body nutrients of the fish were significantly higher in the fish fed n-3HUF A deficient diets than those of the fish fed n-3 HUF A sufficient diets. Protein and lipid contents of the whole body were decreased with starvation whereas moisture content was increased. Decrease of lipid was mainly due to the decrease of nonpolar lipid. Amounts of polar lipid in the whole body were almost constant throughout the starvation, meaning not being affected by dietary n-3HUF A levels. Percentage of 22: 6n-3 was increased in the polar lipid fraction, but monoenic acids (16:1, 18:1), n-3 series (18:3, 18 4, 20:4) and n-6 series (20:2, 22:4, 22:5) were decreased with starvation. Fatty acid compositions of nonpolar lipid were not changed with starvation. These results suggest that all fatty acids of nonpolar lipid are equally utilized for energy during starvation.

• Nutrition Research and Practice
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• v.10 no.2
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• pp.182-187
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• 2016

BACKGROUND/OBJECTIVES: Supplementation with n-3 polyunsaturated fatty acids (PUFAs) has been shown to generally decrease levels of innate immune markers and inflammatory cytokines, but the specific associations between blood levels of PUFAs and those of innate immune markers have not been investigated. Thus, the present study was conducted to test the hypothesis that innate immune markers as well as cytokines are negatively associated with n-3 PUFAs but positively associated with n-6 PUFAs in healthy adults. MATERIALS/METHODS: One hundred sixty-five healthy Korean adults aged 25-70 years old were included in this cross-sectional study. RESULTS: Serum levels of n-3 PUFAs, such as 18:3n3, 20:5n3, 22:5n3, and 22:6n3 were negatively correlated with eosinophil and basophil counts and $TNF-{\alpha}$, $IFN-{\gamma}$, IL-4, and IL-10 levels. Multivariate analysis also showed that serum levels of n-3 PUFAs were negatively associated with monocyte, eosinophil, and basophil counts and $TNF-{\alpha}$, $IFN-{\gamma}$, IL-4, and IL-12 levels. Additionally, the ratio of 20:4n6 to 20:5n3 was positively correlated with eosinophil counts and associated with $TNF-{\alpha}$, $IFN-{\gamma}$, and IL-4 levels. However, NK cell activity was not associated with serum fatty acid composition. CONCLUSIONS: Innate immune markers such as eosinophil, monocyte, and basophil counts were inversely associated with serum levels of n-3 PUFAs, but were positively associated with the 20:4n6/20:5n3 ratio in this population.

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.647-650
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• 2001

• Korean Journal of Environmental Agriculture
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• v.8 no.2
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• pp.93-102
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• 1989

Water pollution status of the irrigation water, inorganic nutrient contents of rice plant, relationship between water quality of irrigation water and inorganic nutrient contents of rice plant, and nitrogen supply by irrigation water at six sites of pumping stations in Kimhae plain were investigated. The results were as follows : 1. Average values of water components analyzed at all pumping stations were in the range of 6.5-7.0 pH, 0.6-7.7ppm DO, 4.4-63.5ppm BOD, 7.3-73.9ppm COD, 1.84-16.22ppm $NH_4$-N, 1.22-15.49ppm $NO_3$-N and 0.07-1.35ppm $PO_4$-P respectively. 2. Comparatively heavy polluted sites were Sikman, Bongrim and Noksan, and less polluted sites were Daejeo, Myeongje and Jangyou, judging from BOD, COD and $NH_4$-N of the irrigation water. 3. Nitrogen supply by irrigated water for a year were 6.82Kg/10a, 5.98Kg/10a, 6.64Kg/10a, 2.31kg/10a, 6.22Kg/10a and 2.54Kg/10a in Daejeo, Sikman, Bongrim, Myeongji and Noksan area, respectively. 4. Positive correlation was observed between ammonium nitrogen of the water and total nitrogen contents of rice plant. Total nitrogen contents of rice plant were higher in Sikman, Borgim and Noksan area than in the other areas.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.3
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• pp.241-249
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• 1993

The class and fatty acid composition of neutral lipid(NL) and phospholipid(PL) of Korean sweetfish were experimented. The NL was mainly consisted of triglyceride ($94.8{\sim}99.5\%$), and also identified free sterol($0.29{\sim}2.77\%$), sterol ester and diglyceride in less quantity. Triglyceride content of viscera was much higher than those of other tissues. Main components in the PL were phosphatidylcholine(PC, $7.9{\sim}61.6\%$), phosphatidyl ethanolamine(PE, $19.3\%{\sim}39.3\%$) and followed by diphosphatidyl glycerol and sphingomyelin. PC and PE contents were higher in muscle and head tissues. The major fatty acids in NL fractions of sweetfish were 16:0, 18:1n-9, 16:1n-7, 18:2n-6, 18:0 and 14:0. Fatty acid composition of NL was similar to those of total lipid and were not significantly different among the fishes, the large and small sweetfish. In case of PL fractions, the major fatty acids were 16:0, 18:1n-9, 22:6n-3, 18:0 and 18:2n-6.

• Nutrition Research and Practice
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• v.13 no.4
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• pp.344-351
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• 2019

BACKGROUND/OBJECTIVES: Adequate dietary fatty acid intake is important for toddlers between 12-24 months of age, as this is a period of dietary transition in conjunction with rapid growth and development; however, actual fatty acid intake during this period seldom has been explored. This study was conducted to assess the intake status of n-3 and n-6 polyunsaturated fatty acids by toddlers during the 12-24-month period using 2010-2015 Korea National Health and Nutrition Examination Survey data. SUBJECTS/METHODS: Twenty-four-hour dietary recall data of 12-24-month-old toddlers (n = 544) was used to estimate the intakes of ${\alpha}$-linolenic acid (ALA; 18:3n-3), eicosapentaenoic acid (EPA; 20:5n-3), docosahexaenoic acid (DHA; 22:6n-3), linoleic acid (LA; 18:2n-6), and arachidonic acid (AA; 20:4n-6), as well as the major dietary sources of each. The results were compared with the expected intake for exclusively breastfed infants in the first 6 months of life and available dietary recommendations. RESULTS: Mean daily intakes of ALA, EPA, DHA, LA, and AA were 529.9, 22.4, 37.0, 3907.6, and 20.0 mg/day, respectively. Dietary intakes of these fatty acids fell below the expected intake for 0-5-month-old exclusively breastfed infants. In particular, DHA and AA intakes were 4 to 5 times lower. The dietary assessment indicated that the mean intake of essential fatty acids ALA and LA was below the European and the FAO/WHO dietary recommendations, particularly for DHA, which was approximately 30% and 14-16% lower, respectively. The key sources of the essential fatty acids, DHA, and AA were soy (28.2%), fish (97.3%), and animals (53.7%), respectively. CONCLUSIONS: Considering the prevailing view of DHA and AA requirements on early brain development, there remains considerable room for improvement in their intakes in the diets of Korean toddlers. Further studies are warranted to explore how increasing dietary intakes of DHA and AA could benefit brain development during infancy and early childhood.

• Korean Journal of Environment and Ecology
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• v.23 no.6
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• pp.564-568
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• 2009

The principal objective of this study was to determine and characterize the food resources and foraging sites of Pacific Reef Herons bred in Aewol-eup, Jeju Island, during Feb. 2005 ~ Aug. 2005. The food resources of Pacific Reef Herons were identified as comprising 21 individuals of 5 species, and these identifications were verified as follows: 38.1% of Tridentoger obscurus(n=8), 19.0% of Ennedpterygius etheostomus(n=4), and 14.3% of Engraulis japonica(n=3). The sizes of the food resources were measured as follows: total $58.29{\pm}5.17mm$(n=19), T. obscurus was $67.49{\pm}4.91mm$(n=8), E. etheostomus was $43.98{\pm}3.50mm$(n=4), and E. japonica was $22.77{\pm}1.17mm$. The semi-digested foods were confirmed as Paralichthys olivaceus and Sebastes inermis. The primary foraging sites were 7.4km(Oedocheon) east, to 6.6km(Geumseongcheon) west of the Aewol breeding area.

• Journal of Life Science
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• v.23 no.8
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• pp.1004-1009
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• 2013

The biochemical compositions and nutritive values of six species of seaweeds were analyzed to determine their applicability in functional foods or ingredients. The biochemical compositions (moisture, ash, protein, lipid, and dietary fiber) and fatty acid contents were determined for the following seaweed extracts: Phaeophyceae (Laminaria japonica, Hizikia fusiformis, and Undaria pinnatifida), Rhodophyceae (Porphyra tenera and Gracilaria verrucosa), and Chlorophyceae (Ulva lactuca). The moisture content (% dry weight) ranged from 11.47% to 13.94%, ash from 19.15% to 26.50%, protein from 5.08% to 15.44%, lipid from 2.75% to 4.43%, and dietary fiber from 36.84% to 52.98%. C14:0, C16:0, C18:0, C16:1, C18: 1n-3, C18:2n-6, C18:3n-6, C20:4n-6, and C20:5n-3 represented the predominant proportions of fatty acids. Interestingly, docosahexaenoic acid (C22:6n-3, DHA) was either not found or only detected in trace amounts in the analyzed seaweeds. The levels of n-3 fatty acid were higher than other polyunsaturated fatty acids, and the n-6/n-3 ratio was very low. These results indicate that seaweed inhabiting Korean coastal areas will be beneficial to human health.