• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2001.04a
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• pp.11-14
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• 2001

In this study, the relationship between metals (Cu, Cr, Cd, Zn. Pb, and Fe) 5 fractions and toxicity of soil samples from various contaminated sites in Korea were investigated. Metal toxicity of soils was tested using MetPLATE$^{TM}$ test kit, which is known as metal sensitive and organic insensitive. Significant amount of Fe was found in soils, and metal contents were in the order of Fe>Zn>Pb>Cu>Cr>Cd. Metal levels in organic fraction were rather high for all metals except Fe, and quite high percentages (35~79%) for residual fraction were observed for all metals. There were no significant relationships between the content of each metal fraction and toxicity which showed regression $R^2$in the range of 0.0003~0.414. However, correlation between toxicity and total metal contents showed regression coefficient $R^2$= 0.72. These results showed that the risk evaluation of metals in contaminated sites should be difficult to assess only by the contents of metal distribution because of the complexity of mixture of various metals.s.

• Journal of Nutrition and Health
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• v.33 no.2
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• pp.147-157
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• 2000

This study examined the effects of excess intake of calcium (Ca) and iron (Fe) supplement on bone loss, nephrocalcinosis and renal function in osteoporotic model rats. Seven-week-old female rats were first fed a Ca-deficient diet for four weeks after ovariectomy operation, and then one of nine experimental diets for additional eight weeks, containing three levels of Ca, normal (0.5%) or high (1.5%) or excess (2.5%) and three levels of Fe, normal (35ppm) or high (210ppm) or excess (350ppm). The osteoporotic model rats showed a remarkable increase in body weight, serum alkaline phosphatase (ALP) and decrease in breaking force, Ca, P, Mg contents of femur. Serum Ca concentration was not significantly affected by dietary Ca and Fe levles. Liver Ca content increased in rats fed a high-and excess-Ca diet. Kidney Ca content and microscopic Ca deposition remarkably increased in osteoporotic model rats compared to control group, and showed a tendency to decrease in rats fed a excess-Ca diet. Breaking force of femur increased with increasing dietary Ca levels, but Ca, P contents of femur and serum ALP were not significantly affected by dietary Ca and Fe levels. Serum total protein decreased in rats fed a excess-Ca diet, BUN increased in rats fed a excess-Ca diet, while serum uric acid and creatinine were not significantly affected by dietary Ca levels. Urinary creatinine, GFR increased in rats fed a high-and excess-Ca, diet, and GFR was highest in rats fed a excess-Ca/excess-Fe diet. These results suggest that excess intake of Ca may increase breaking force of femur, but not increase mineral contents of femur, and decrease kidney function. Furthermore, excess intake of Fe and Ca concurrently may aggravate kidney function leading to potential health problems in ovariectomized osteoporotic model rats.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.2
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• pp.93-104
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• 2004

This pot experiment was conducted to investigate the effects of combined micronutrient application($T_1$; control, $T_2$; Fe, $T_3$; Fe+Mn, $T_4$; Fe+Mn+Cu, $T_5$ ; Fe+Mn+Cu+Zn, $T_6$ ; Fe+Mn+Cu+Zn+Mo, T$_{7}$; Fe+Mn+Cu+Zn + Mo + B) on forage performance of pure and mixed cultures of orchardgrass and white clover. The fifth part was concerned with the changes in the total and relative contents, uptake amounts, and mutual ratios. of micronutrients in forages. The results obtained are summarized as follows: 1. The relative contents(total contents of 6 micronutrients = 100%) of Fe and Mn were considerably influenced by the antagonism between Fe and Mn, and also were influenced by the differences in Mn-absorption between orchardgrass and white clover. Compared with pure culture, orchardgrass showed high relative contents of Mn, and low relative contents of Fe and B in mixed culture. White clover, however, tended to be exactly opposed to the above trends. In relative contents, the T$_6$ 6/ resulted generally in decrease of Fe. However the $T_7$ resulted in increase of Mn and B. In addition, the $T_7$ resulted in decrease of Cu and Zn in orchardgrass, and Mo in white clover. 2. In general, there were differences in the tendency between the yield changes and the uptake amounts of micronutrients. General differences have been showed in the uptake amounts and mutual ratios of micronutrients based on the forage species, pure/mixed culture, additional fertilization, and antagonism. The uptake amounts of total micronutrients were generally increased by the treatments with increased combination. In uptake amounts, the $T_7$ resulted in the increase of Mn and B, and decrease of Mo. 3. The mutual ratios of Fe/Mn, Fe/Cu, and Mn/Cu were considerably influenced by the antagonism between Fe and Mn. At the $T_7$ , very low ratio of Fe/Mo affected by the T6 tended to be somewhat improved because of the decrease of Mo content． The poor growth of forages at the $T_6$ was improved by the $T_7$ . This fact was likely to be caused by the adequate B/Mo ratio.

• Journal of the Korean Society of Food Culture
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• v.16 no.3
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• pp.235-242
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• 2001

Chemical properties of the different parts of watercress(Oenanthe javanica D.C.) grown and harvested from the culture fields under different cultivating methods were studied. In proximate analyses of watercress in parts, moisture contained more in stem than in root or in leaf, but crude protein and crude lipid contents were lower in stem than in root or in leaf. Crude ash in root contained up to about double amount in leaf or stem. Major mineral elements detected in watercress were Fe, Mg, Ca, and K, and their contents in root was higher than those in stem or leaf. Especially, Fe in root was significantly higher than that in stem or in leaf. Total free sugar composed mainly with fructose and glucose, was the highest in watercress from Hwasoon and followed the watercress from Jeonju and Donggok in order. Free sugar content was highest in leaf and the lowest in root. Major water-soluble vitamins were vitamin C, thiamin and biotin and the content of vitamin C was higher than others. These vitamins contained more in leaf than in stem or root. Niacin contained 6.09 mg/100 g in leaf of watercress from Hwasoon, which was much higher than others, but it was not detected in stem of watercress from Jeonju. Organic acids detected were oxalic acid, citric acid and malic acid and other 12 organic acids were not detected. In fatty acid composition, there were significant differences among watercresses from different parts and different culture fields. Linoleic acid, linolenic acid and palmitic acid were major fatty acids contained in watercress and it took about 80% of the total content. Amino acid content in leaf was higher than that in root and in stem. Glutamic acid and proline were major amino acids in stem of watercress from Jeonju and in stem of watercresses from Hwasoon and Donggok, respectively. In leaves of all three watercresses glutamic acid content was the highest.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.527-534
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• 1999

This study was carried out to investigate the effects of pine needle extracts on lipid oxidation and free radical reaction in iron sources reacted with active oxygen species. The results were summarized as follow; the catalytic effects of active oxygen on lipid oxidation in oil emulsion tended to be showed $OH,\;H_2O_2\;and\;KO_2$ in order. At the same time, pine needle extracts itself were tended to be showed a little catalytic effects. Active oxygen scavenging ability of pine needle extracts didn't show, but pine needle extracts played role as a strong chelating agents to bind iron ion if $Fe^{2+}$ ion exist in oil emulsion. The content of $Fe^{2+}$ ion and total iron in CPNP were higher than those of HPNP and FPN. The content of ascorbic acid of FPN showed the highest (87.77 ppm) among several pine needle extracts. Electron donating ability of HPNP and CPNP were 81% and 78%, respectively, which were showed higher content than those of FPN. The SOD-like activity of HPNP showed 44.30%, compared to other pine needle extracts which means the most strong antioxidant reaction. The nitrite scavenging effects were tended to be different, depending on pH value as pH value was increased. Especially, they didn't show the nitrite scavenging effect in pH6.0.

• Korean Journal of Community Nutrition
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• v.5 no.2
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• pp.243-252
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• 2000

This study examined the effects of excess intake of calcium(Ca) and iron(Fe) supplements on iron bioavailability, liver and kidney functions in anemic model rats. Seven-week-old female rats were first fed and Fe-deficient diet for ten weeks, and then fed one of nine experimental diets for an additional eight weeks, containing three levels of Ca, normal (0.5%) or high(1.5%) or excess (2.5%) and three levels of Fe, normal(35ppm) or high(210 ppm) or excess(350ppm). In anemic model rats, serum Fe, total iron binding capacity(TIBC), hemogolin(Hb), hematocrit(Hct) and liver Fe contents were significantly decreased. Apparent Fe absorption significantly increased with increasing dietary Fe levels, and decreased with increasing dietary Ca levels. serum Fe concentration significantly increased in rats fed a high- and excess-Fe diet, and decreased in rats fed a excess-Ca diet. TIBC was decreawed in rats fed a excess-Ca diet, and transferrin saturation(%) increased in rats fed ahigh- and excess-Fe diet. Hb and Hct were decreased in rats fed an excess-Ca diet regardless of dietary Fe levels. Fe and thiobarbituric acid reactin gsubstance(TBARS) Contents of liver significantly increased in rats fed a high- and excess0-Fe diet, and decreased in rats fed a high- and excess-Ca diet. Fe content of the spleen showed similar results. Urinary creatinine and GFR increased in rats fed an excess-Ca diet regardless of dietary Fe levels. GOT, GPT and LDH were not significantly affected by dietary Ca and Fe levels. These results suggest that excess intake of Fe may increase liver Fe deposits and TBARS, and excess intake of Ca may decrease Fe bioavailability and kidney function leading to potential health problems in anemic model rats.

• Advances in materials Research
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• v.4 no.4
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• pp.227-233
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• 2015

We present a method, supported by theoretical analysis, for optimizing the usage of the critical rare earth element dysprosium in $Nd_2Fe_{14}B$ (NdFeB)-based permanent magnets. In this method, we use Dy selectively in locations such as magnet edges and faces, where demagnetization factors are largest, rather than uniformly throughout the bulk sample. A200 nm thick Dy film was sputtered onto a commercial N-38, NdFeB magnets with a thickness of 3 mm and post-annealed at temperatures from $600-700^{\circ}C$. Magnets displayed enhanced coercivities after post-annealing and as much as a 5 % increase in the energy product, while requiring a total Dy content of 0.06 wt. % - a small fraction of that used in the commercial grade Dy-NdFeB magnets. By assuming all Dy diffused into NdFeB magnets, the improvement in energy product corresponds to a saving of over 1% Dy (critical element). Magnets manufactured using this technique will therefore be higher performing which would potentially broaden the application space of these magnets in the traction motors of hybrid and pure electric vehicles, and wind generators.

• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.51-58
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• 2017

Antioxidant activities of 80% methanol, water, and 70% ethanol extracts of Lentinula edodes GNA01 were compared and estimated. The yield of Lentinula edodes GNA01 was identified to be in the following order: water>70% ethanol>80% methanol, but there was no significant difference between 80% methanol and 70% ethanol extracts. The highest total phenolic content (TPC) and total flavonoid content (TFC) were found in water extract, and TPC of 80% methanol extract was higher than that of 70% ethanol extract and TFC of 70% ethanol extract was higher than that of 80% methanol extract. Water extract exhibited the strongest DPPH, ABTS radicals, and nitrite scavenging activities, $Fe^{2+}$ chelating ability, and FRAP among the three extracts. In addition, antioxidant activity of 80% methanol extract was higher than that of 70% ethanol extract in most of the experiments. As a result, antioxidant activity of Lentinula edodes GNA01 showed a difference according to extraction solvent and concentration; nevertheless, water extract exhibiting high polarity had the strongest antioxidant effect. Consequently, water extract from Lentinula edodes GNA01 is anticipated to be useful for the development of a high value-added functional product.

• The Korean Journal of Food And Nutrition
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• v.12 no.6
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• pp.575-581
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• 1999

In result of chemical properties of bamboo shoots and changes of chemical components of salted bamboo shoots during 120 days salting, the contents of moisture crude fat tannin and ascorbic acid were decreased but those of crude protein curde ash and salt concentration were increased. The main free amino acids of bamboo shoots were serine arginine alanine leucine and tyrosine. The content of total free amino acid was rapidly decreased in 80days-past of salting and after that slowly decresed. Wang bamboo shoots was the highest as 1060.18mg/100g in content of total free amino acid. The main mineral elements were K, P, Na and Mg. The contents of Fe and K were the hihest among them. The contents of P, Fe, Zn. Mn. Ge and Cu were decreased but K, Mg, Na and Ca were increased during salting. When fresh bamboo shoots were compared with salted bamboo shoots fresh bamboo shoots contained the contents of moisture crude protein crude fat tannin and ascorbic acid more than salted bamboo shoots did but the less the contents of ash fiber and salt concentration.

• Journal of Nutrition and Health
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• v.40 no.6
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• pp.558-565
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• 2007

On the basis of the increasing interest for the selection of beverages, this study aimed to evaluate the contents of nutrients and health ${\cdot}$ functional elements in the beverages. Total 161 beverages that bear nutrition lable (NL) as nutrition table and health ${\cdot}$ functional elements information were collected and classified to 8 groups. The evaluated nutrients that are obligatory for NL in Korea were total calorie, carbohydrate, protein, fat, and sodium. Presented values showed that milk & yogurt and soy milk are the most wholesome beverages while the total caloric contents also were higher among 8 groups. Sodium contents in soy milk were higher than any other groups. The caloric contents of other beverage groups come mainly from carbohydrate presumably simple sugar. The caloric content of sports drinks is the lowest but the sodium content is variable among products showing the range of 0 - 100 mg/100 ml. Nonobligatory nutrients for NL frequently expressed are Ca, Fe, vitamin C, folate, and dietary fiber. Their content per serving size does not exceed the tolerable upper intake level, however, habitual multiple intakes of certain product require attention for the prevention of overintakes. Many health ${\cdot}$ functional elements as catechin, carnitine, polyphenol, and nucleic acids etc were listed in NL without presenting the content and their functions appear to be exaggerated compared to the known scientific evidence.