• Clinical and Experimental Pediatrics
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• v.57 no.8
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• pp.345-350
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• 2014

Iron deficiency affects approximately one-third of the world's population, occurring most frequently in children aged 6 months to 3 years. Mechanisms of iron absorption are similar to those of other divalent metals, particularly manganese, lead, and cadmium, and a diet deficient in iron can lead to excess absorption of manganese, lead, and cadmium. Iron deficiency may lead to cognitive impairments resulting from the deficiency itself or from increased metal concentrations caused by the deficiency. Iron deficiency combined with increased manganese or lead concentrations may further affect neurodevelopment. We recently showed that blood manganese and lead concentrations are elevated among iron-deficient infants. Increased blood manganese and lead levels are likely associated with prolonged breast-feeding, which is also a risk factor for iron deficiency. Thus, babies who are breast-fed for prolonged periods should be given plain, iron-fortified cereals or other good sources of dietary iron.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.14-20
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• 2006

During the 11 year period of 1995-2005, there was about a 40% increase in the world copper demand mainly because of the Asian economic growth. In the increase, about a half was consumed by China. Most of the China's copper demand increase has been taken place over the final 5-6 years of that period. The growth is expected to continue for several years, and in 10 years or sooner the same situation is expected for India. Copper is the third metal in global demand, but its little abundance in the Earth's crust is not well recognized. From the production rate and the abundance, a copper shortage, or crisis, has a high probability than the other metals. Deep ocean mineral resources such as manganese nodules in the Clarion-Clipperton Fracture Zones, Kuroko-type massive seafloor sulfides (SMS), and cobalt-rich manganese crusts in the EEZ and the high sea areas have big potentials for the future sources. We need to re-evaluate their potentials as copper resources and other metals to realize their developments. The same situation is under progress in the hydro-carbon markets. Methane hydrates that are classified into non-conventional hydro-carbon resources have an important role as the future sources, too.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.447-452
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• 2007

This study was peformed to estimate manganese intake and the major food source of manganese in Korean adults. The 354 subjects aged over 20 years were measured anthropometrics and dietary intake using 24-hour recall method. Daily intake and the major food sources of manganese were calculated using manganese database of food composition tables in Korea, USA and Japan. The average age, height, weight and BMI were 54.6years, 165.7cm, 67.2kg and $24.5kg/m^2$ for men and 53.8 years, 153.7cm, 59.1kg and $24.9kg/m^2$ for women, respectively. The daily energy and manganese intake of men were significantly higher than those of women (1740.9 kcal vs. 1432.6 kcal; p<0.001, 3.7mg vs. 3.2mg; p<0.01). However, daily manganese intake per 1000kcal between men and women was not significantly different (2.2mg/1000kcal vs. 2.3mg/1000kcal). Daily manganese intakes from each food group were 1.9mg from cereals, 0.5mg from vegetables, 0.4mg from pulses and 0.2mg from seasonings. The 20 major food sources of dietary manganese were rice, soybean, sorghum, Kimchi, tobu, wheat flour, red pepper powder, small red bean, glutinous millet, soybean paste, potato, Ramyeon, green pepper, noodle, buckwheat Naengmyeon, soybean sprout, laver, watermelon, perilla seeds powder and soy sauce. Manganese intake from these 20 foods was 74.0% of the total dietary manganese intake. In conclusion, daily manganese intake of the subject was 3.4mg (2.2mg/1000 kcal) and met adequate intake of manganese. The mai or food sources of manganese were cereals, pulses, and vegetables such as rice, soybean, sorghum, Kimchi and tobu.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.12-16
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• 1995

Medium components for lactic acid production were optimized with a strain of Lactobacillus sp., isolated by our Lab. Nitrogen source was the key component and manganese ion was also important for lactic acid production in this strain. Optimal concentration of manganese ion was 0.03 g/l as MnSO$_{4}$ 4 - 5 H$_{2}$O base. Other mineral elements, however, had little effect on it. Among the nitrogen sources we examined, yeast extract showed the highest productivity. Yeast extract, the exellent but very expensive medium component, could be partially replaced by soytone until 60% dry base with higher productivity, or by tryptone enforced with vitamines and nucleic acids. In order to replace yeast extract completely, we examined several inexpensive nitrogen sources and their enzymatic hydrolyzates. The hydrolyzate of vital wheat gluten was the best of them.

• Journal of Powder Materials
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• v.24 no.2
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• pp.87-95
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• 2017

Lithium silicate, a lithium-ion conducting ceramic, is coated on a layer-structured lithium nickel manganese oxide ($LiNi_{0.7}Mn_{0.3}O_2$). Residual lithium compounds ($Li_2CO_3$ and LiOH) on the surface of the cathode material and $SiO_2$ derived from tetraethylorthosilicate are used as lithium and silicon sources, respectively. Powder X-ray diffraction and scanning electron microscopy with energy-dispersive spectroscopy analyses show that lithium silicate is coated uniformly on the cathode particles. Charge and discharge tests of the samples show that the coating can enhance the rate capability and cycle life performance. The improvements are attributed to the reduced interfacial resistance originating from suppression of solid-electrolyte interface (SEI) formation and dissolution of Ni and Mn due to the coating. An X-ray photoelectron spectroscopy study of the cycled electrodes shows that nickel oxide and manganese oxide particles are formed on the surface of the electrode and that greater decomposition of the electrolyte occurs for the bare sample, which confirms the assumption that SEI formation and Ni and Mn dissolution can be reduced using the coating process.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1408-1413
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• 2003

This study was conducted to analyze manganese contents of Korean common foods. Contents of manganese in 30 foods were analyzed by ICP spectrometer. And daily manganese intake through 30 common foods was calculated using analysis data of this study and daily food intakes cited from report on 1998 national health and nutrition survey. The average manganese contents of foods analyzed were 949.6 $\mu\textrm{g}$ for rice, 236.1 $\mu\textrm{g}$ for Korean chinese cabbage kimchi, 27.2 $\mu\textrm{g}$ for citrus fruit, 2.6 $\mu\textrm{g}$ for milk, 214.6 $\mu\textrm{g}$ for radish root, 40.0 $\mu\textrm{g}$ for apple, 60.4 $\mu\textrm{g}$ for persimmon, 13.9 $\mu\textrm{g}$ for pork, 9.5 $\mu\textrm{g}$ for beef, 638.3 $\mu\textrm{g}$ for soybean curd, 184.0 $\mu\textrm{g}$ for radish kimchi, 56.0 $\mu\textrm{g}$ for pear, 18.4 $\mu\textrm{g}$ for beer, 11.3 $\mu\textrm{g}$ for egg, 9.5 $\mu\textrm{g}$ for carbonated beverage, 345.0 $\mu\textrm{g}$ for bread, 50.7 $\mu\textrm{g}$ for soju, 270.3 $\mu\textrm{g}$ for potato, 236.1 $\mu\textrm{g}$ for sweet potato, 91.2 $\mu\textrm{g}$ for ramyeon, 32.5 $\mu\textrm{g}$ for onion, 68.0 $\mu\textrm{g}$ for nabak kimchi, 538.2 $\mu\textrm{g}$ for soybean sprout, 112.5 $\mu\textrm{g}$ for welsh onion, 336.7 $\mu\textrm{g}$ for rice cake, 589.9 $\mu\textrm{g}$ for Korean chinese cabbage, 430.4 $\mu\textrm{g}$ for somyeon, 144.3 $\mu\textrm{g}$ for pumpkin, 3.0 $\mu\textrm{g}$ for yoghurt, and 614.4 $\mu\textrm{g}$ for spinach per 100 g of each food. The daily manganese intake through 30 common foods of Koreans in 1998 was 3420.7 $\mu\textrm{g}$. Major sources of dietary manganese were rice, kimchi, and soybean curd. Especially, rice supplied 68.1% of total dietary manganese intake through 30 common foods. Further studies are required to establish database and RDA of manganese.

• Microbiology and Biotechnology Letters
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• v.30 no.3
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• pp.258-263
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• 2002

In this study the effects of temperature, pH, and addition of some minerals were investigated in lactic acid fermentation using Enterococcus faecalis RKYI . As a result, strain of RKYl had retained biological activity at the wide range of temperature($34-46^{\circ}C$) and pH(6.0-9.0), and the optimum temperature and pH were $42^{\circ}C$ and 7.0, respectively. When the effect of various phosphate sources added on lactic acid fermentation was studied, di-basic forms of phos-phate(especially, ammonium phosphate and potassium phosphate) had more stimulating effect rather than mono-basic phosphate sources. And there were no perceivable effect of manganese and magnecium salts addition on lactic acid fermentation.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.226-231
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• 2006

Several white-rot fungi are able to produce extracellular lignin-degrading enzymes such as manganese peroxidase (MnP), lignin peroxidase (LiP), and laccase. In order to enhance the production of laccase and MnP using Trametes versicolor KCTC 16781 in suspension culture, the effects of major medium ingredients, such as carbon and nitrogen sources, on the production of the enzymes were investigated. The decolorization mechanism in terms of biodegradation and biosorption was also investigated. Among the carbon sources used, glucose showed the highest potential for the production of laccase and MnP. Ammonium tartrate was a good nitrogen source for the enzyme production. No significant difference in the laccase production was observed, when glucose concentration was varied between 5 g/l and 30 g/l. As the concentration of nitrogen source increased, a lower MnP activity was observed. The optimal C/N ratio was 25 for the production of laccase and MnP. When the concentrations of glucose and ammonium tartrate were simultaneously increased, the laccase and MnP activities increased dramatically. The maximum laccase and MnP activities were 33.7 U/ml at 72 h and 475 U/ml at 96 h, respectively, in the optimal condition. In this condition, over 90% decolorization efficiency was observed.

• Membrane and Water Treatment
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• v.7 no.4
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• pp.277-296
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• 2016

The aim of this research was to investigate the ability of nanofiltration (NF) and ultrafiltration (UF) membranes as a filtration unit for groundwater treatment for drinking water resources. Commercial membranes denoted as TS40, TFC-SR3 and GHSP were used to study the performance based on rejections and fluxes. The investigation has been conducted using natural groundwater obtained from a deep tube well with initial concentration of iron (Fe) and manganese (Mn) at 7.15 mg/L and 0.87 mg/L, respectively. Experimental results showed that NF membranes exhibited higher fluxes than UF membrane with pure water permeability at 4.68, 3.99 and $3.15L.m^{-2}.h^{-1}.bar^{-1}$, respectively. For metal rejection, these membranes have performed higher removal on Fe with TS40, TFC-SR3 and GHSP membranes having more than 82%, 92% and 86% respectively. Whereas, removal on Mn only achieved up to 60%, 80% and 30%, for TS40, TFC-SR3 and GHSP membranes respectively. In order to achieve drinking water standard, the membranes were efficient in removing Fe ion at 1 and 2 bar in contrast with Mn ion at 4 and 5 bar. Higher rejection of Fe and Mn were achieved when pH of feed solution was increased to more than 7 as TFC-SR3 membrane was negatively charged in basic solution. This effect could be attributed to the electrostatic effect interaction between membrane material and rejected ions. In conclusion, this study proved that NF membrane especially the TFC-SR3 membrane successfully treated local groundwater sources for public drinking water supply in line with the WHO standard.

• Nutrition Research and Practice
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• v.5 no.6
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• pp.548-552
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• 2011

The purpose of this study was to estimate the daily manganese (Mn) intake of Korean children. This study was done using a three-day dietary intake survey of 257 Korean children (boys 123; girls 134). The Mn intake values were calculated based on a database that provides the Mn content of the frequently consumed Korean foods, alongside the food composition table provided by the Korean National Rural Living Science Institute. The average age, height, weight and body mass index of our subjects were 11.9 years, 155.4 cm, 48.9 kg and 20.2 kg/$m^2$ in boys and 11.9 years, 154.1 cm, 43.5 kg and 18.3 kg/$m^2$ in girls. The average daily energy intakes were 2,249.2 kcal in boys and 2,044.5 kcal in girls. Boys consumed significantly more Mn than girls, based on intake estimates of $4,585.3{\mu}g$ (117.6% of adequate intake) and $4,029.3{\mu}g$ (117.1% of adequate intake), respectively (P < 0.001). Boys had a Mn intake of $2,041.1{\mu}g$ per 1,000 kcal of energy consumption, whereas for girls this was at $1,983.9{\mu}g$ per 1,000 kcal. Neither group exceeded the tolerable upper intake level for Mn. The major food groups which contributed to Mn intake in our subjects were cereals (50.8%), vegetables (21.0%), seasonings (8.9%), and pulses (7.7%). Notably, boys derived a higher Mn intake through cereals and vegetable than did girls (P < 0.001, P < 0.05). The key food sources of Mn, in descending order, were rice, soybean curd, kimchi, black rice and cereals. We propose that the results of our study may be used as a basis for follow-up studies that examine the Mn intake of children.