• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.466-475
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• 2005

Docosahexaenoic acid (22:6n-3, DHA) is highly enriched in membrane of brain and retina, and plays an important role in maintaining an optimal function of the central nervous system. We investigated the effect of n-3 fatty acid deficiency on rat brain, retina and liver fatty acyl composition at two different ages (3 wks and 15 wks) under DHA deficient condition. Rat pups born to dams fed a diet with $3.1\%$ of total fatty acids as $\alpha-linolenic$ acid (LNA) were fed using an artificial rearing system either an n-3 deficient (n-3 Def) or n-3 adequate (n-3 Adq) diet. Both diets contained $17.1\%$ linoleic acid (LA) but the n-3 Adq diet also contained $3.1\%$ LNA. Rats consuming the n-3 Def diet showed a lower brain $(50\%\;in\;13\;wks\;and\;70\%\;in\;15\;wks,\;p<0.05)$ and retinal $(50\%\;in\;13\;wks\;and\;63\%\;in\;15\;wks,\;p<0.05)$ DHA than those on the n-3 Adq diet, which was largely compensated for by an increase in docosapentaenoic acid (22:5n-6, DPAn-6). In the liver of the n-3 Def group, the percentage of DHA decreased by $97\%$ at 3 wks of age with an apparent increase in DPAn-6 relative to the n-3 Adq group (p<0.05), while there was a $65\%$ lower liver DHA in n-3 Def group at 15 wks of age than the n-3 Adq group (p<0.05). Liver arachidonic acid (20:4n-6, AA) was increased at 3 wks of age but decreased at 15 wks of age in the n-3 Def group compared with n-3 Adq group (p<0.05). In conclusion, the replacement of DHA by DPAn-6 in brain and retina fatty acid composition may be related to the suboptimal function in spatial learning, memory and visual acuity. This artificial rearing method presents a first generation model for n-3 deficiency that is similar to the case of human nutrition that commonly employed two generation model.

• Journal of Nutrition and Health
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• v.49 no.2
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• pp.63-71
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• 2016

Purpose: Skin pH, an indicator of skin health, is maintained by various organic factors, which include lactate, free amino acid (FAA), and free fatty acid (FFA). As skin ages or with illness, skin pH becomes less acidic, and functional food has been developed to maintain the acidic pH of skin. In this study, we determined the dietary effect of green tea extract (GTE) on skin pH of photo-aged mice, as measured by epidermal levels of lactate, FAA, and FFA. The protein expression and activity of lactate dehydrogenase (LDH), an enzyme of pyruvate reduction for lactate generation, was further determined. Methods: Albino hairless mice were fed a control diet (group UV+) or a diet with 1% GTE (group GTE) in parallel with UV irradiation for 10 weeks. A normal control group was fed a control diet without UV irradiation for 10 weeks (group UV-). Results: Skin pH was higher (less acidic) in group UV+ than in group UV-. In parallel, epidermal levels of lactate and FFA, as well as of LDH protein expression and activity, were reduced in group UV+. Dietary supplementation of GTE (group GTE) reduced skin pH to similar to the level of group UV-, and inversely increased epidermal levels of lactate, LDH protein expression and activity, but not of FFA. Although epidermal levels of FAA were similar in groups UV- and UV+, it was increased in group GTE to a level higher than in group UV-. In further analysis of major FFA, epidermal levels of palmitic acid [16:0], oleic acid [18:1(n-9)], and linoleic acid [18:2(n-6), but not of stearic acid [18:0] in group GTE were similar to or lower than those in group UV+. Conclusion: Dietary GTE normalized skin pH with increased levels of lactate and FAA, as well as with increased protein expression and activity of LDH in the epidermis of UVB irradiated hairless mice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.1
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• pp.161-174
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• 1997

Omega-3 fatty acids have been major research interests in medical and nutritional science relating to life sciences since after the epidemiologic data on Green3and Eskimos reported by several researchers clearly showed fewer per capita deaths from heart diseases and a lower incidence of adult diseases. Linolenic acid(LNA) is an essential fatty acid for human beings as well as linoleic acid(LA) due to the fact that vertebrates lack an enzyme required to incorporate a double bond beyond carbon 9 in the chain. In addition the ratio of omega-6 and 3 fatty acids seems to be important in terms of alleviation of heart diseases since LA and LNA competes for the metabolic pathways of eicosanoids synthesis. High consumption of omega-3 fatty acids in seafoods may control heart diseases by reducing blood cholesterol, triglyceride, VLDL, LDL and increasing HDL and by inhibiting plaque development through the formation of antiaggregatory substances like PGI$_2$, PGI$_3$ and TXA$_3$ metabolized from LNA. Omega 3 fatty acids also play an important role in neuronal developments and visual functioning, in turn influence learning behaviors. Current dietary sources of omega-3 fatty acids are limited mostly to seafoods, leafy vegetables, marine and some seed oils and the most appropriate way to provide omega-3 fatty acids is as a part of the normal dietary regimen. The efforts to enhance the intake of omega-3 fatty acids due to several beneficial effects have been made nowadays by way of food processing technology. Two different ways can be applied: one is add Purified and concentrated omega-3 fatty acids into foods and the other is to produce foods with high amounts of omega-3 fatty acids by raising animals with specially formulated feed best for the transfer of omega-3 fatty acids. Recently, items of manufactured and marketed omega-3 fatty acids fortified foodstuffs are pork, milk, cheese, egg, formula milk and ham. In domestic food market, many of them are distributed already, but problem is that nutritional informations on the amounts of omega-3 fatty acids are not presented on the labeling, which might cause distrust of consumers on those products, result in lower sales volumes. It would be very much wise if we consume natural products, result in lower sales volumes. It would be very much wise if we consume natural products high in omega-3 fatty acids to Promote health related to many types of adult diseases rather than processed foods fortified with omega-3 fatty acids.

• Journal of Nutrition and Health
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• v.48 no.6
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• pp.476-487
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• 2015

Purpose: This study was conducted to examine the concentration of nutrients in transitional breast milk from Korean lactating mothers and to evaluate daily intakes of their infants based on the Dietary Reference Intakes for Koreans 2010 (KDRIs 2010). Methods: Breast milk samples were collected at 5~15 days postpartum from 100 healthy lactating Korean mothers. Macro- and micro-nutrients, and immunoglobulin (Igs) concentrations in breast milk were analyzed. Results: The mean energy, protein, fat, and carbohydrate concentrations in breast milk were $59.99{\pm}8.01kcal/dL$, $1.47{\pm}0.27g/dL$, $2.88{\pm}0.89g/dL$, and $6.72{\pm}0.22g/dL$. The mean linoleic acid (LA), a-linolenic acid (ALA), arachidonic acid (AA), and docosahexaenoic acid (DHA) concentrations were $181.44{\pm}96.41mg/dL$, $28.15{\pm}8.89mg/dL$, $5.67{\pm}1.86mg/dL$, and $5.74{\pm}2.57mg/dL$. The mean vitamin A, vitamin D, vitamin E, vitamin $B_1$, vitamin $B_2$, vitamin $B_{12}$, and folate concentrations were $2.75{\pm}1.75{\mu}g/dL$, $2.31{\pm}1.12ng/dL$, $0.74{\pm}1.54mg/dL$, $3.02{\pm}1.84mg/dL$, $7.51{\pm}20.96{\mu}g/dL$, $61.78{\pm}26.78{\mu}g/dL$, $63.71{\pm}27.19ng/dL$, and $0.52{\pm}0.26{\mu}g/dL$. The mean concentrations of calcium, iron, potassium, sodium, zinc, and copper were $20.71{\pm}3.34mg/dL$, $0.59{\pm}0.86mg/dL$, $66.71{\pm}10.35mg/dL$, $27.72{\pm}10.16mg/dL$, $0.44{\pm}0.41mg/dL$, and $70.48{\pm}30.41{\mu}g/dL$. The mean IgA and total IgE concentrations were $61.85{\pm}31.97mg/dL$ and $235.00{\pm}93.00IU/dL$. The estimated daily intakes of infants for protein, vitamin D, vitamin E, vitamin $B_2$, vitamin $B_{12}$, iron, potassium, sodium, zinc, and copper were sufficient compared to KDRIs 2010 adjusted by transitory milk intakes. The estimated infants' intakes of energy, fat, carbohydrate, vitamin A, vitamin C, vitamin $B_1$, folate, and calcium did not meet KDRIs 2010 adjusted by transitory milk intakes. Conclusion: In general most estimated nutrient intakes of Korean breast-fed infants in transitory breast milk were sufficient, however some nutrient intakes were not sufficient based on KDRIs 2010. These results warrant conduct of future studies for investigation of important dietary factors associated with nutrients in breast milk to improve the quality of breast milk, which may contribute to understanding nutrition in early life and promoting growth and development of breast-fed infants.