• Journal of the Korean Chemical Society
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• v.9 no.1
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• pp.61-65
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• 1965

Metal distribution in the reaction products and system of reactions between organo chloro acid or ester and zinc, silicon, magnesium, and tin under acetonitrile, dioxane, and toluene solvent were determined by means of radioactive tracer prepared by means of a (n, ${\gamma}$) reaction. It was found that the solubility of the organo halogen metal complex was markedly increased in a hydrophilic solvent and was decreased in a nonpolar solvent which resulted in an increased metal distribution in the recovered metal or water washing of the recovered metal mixture. This was also true in the case of the reaction conducted in the presence of a carbonyl compound. The relative increase of the solubility of the metal complex in a hydrophilic solvent was in order of zinc, silicon, tin and magnesium, and in a nonpolar solvent, it was in order of silicon, tin, magnesium, and zinc. There was no formation of organo metallics throughout the reaction sequence. The result was discussed and the observed solvent influence on the present reaction path was criticized.

• Journal of the Korean Chemical Society
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• v.38 no.8
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• pp.608-615
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• 1994

The isolation, purification and characterization of a carotenoprotein from the carapace of Pnaeus orientalis were investigated. The carotenoprotein was purple with broad λmax between 480, 409, 318 and 280 nm. Apparent structures were estimated by using X-ray diffractometry and scanning electron microscope, respectively. The molecular weight of the carotenoprotein complex had been determined by GPC and PAGE. The heavier complex, designated the $\alpha$-form (M.W = 170 KDa), was dissociated to a major subunit, $\beta$-form (M.W = 42 KDa). SDS-PAGE of $\alpha$-form showed apparently oligomeric pattern, and also $\beta$-form gave two polypeptides corresponding to 22 KDa and 19 KDa, respectively. The amino acid of the two proteins $({\alpha}-and\;{\beta})$-form, lipid and free fatty acid compositions were described. The prosthetic groups of the carotenoprotein were confirmed by TLC, IR, $^1H$-NMR, MS and various organic reactions as astaxanthin, astaxanthin monoester and astaxnathin diester.

• Journal of the Korean Chemical Society
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• v.29 no.6
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• pp.615-622
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• 1985

The chemical species formed by uranium and vanadium and their equilibria have been investigated in the various concentrations of oxalic and acetic acids by the ion exchange chromatography and UV-Vis spectrophotometry. Uranyl and vanadyl ions seem to be form the complex as $UO_2(C_2O_4)_2=$, $UO_2(C_2O_4)_3^{4-}$ and $VO_2(C_2O_4)-2^{3-}$ respectively in the concentration range of 0.005∼0.05M oxalic acid concentration. In the case of acetic acid the equilibria of $UO_2^{2+}+3Ac^-=UO_2(Ac)_3^-$ and $VO_2^++2Ac^-=VO_2(Ac)_2^-$ were existed individually according to the increase of acetic acid concentration.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.3
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• pp.242-247
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• 2017

Humic acid (HA) is a complex organic matter found in the environments, especially in grassland soils with a high density. The bioactivity of HA to promote plant growth depends largely on its extraction sources. The quality-control of HA and the quality improvements via an artificial synthesis are thus challenging. We recently reported that a polymeric product from fungal laccase-mediated oxidation of catechol and vanillic acid (CAVA) displays a HA-like activity to enhance seed germination and salt stress tolerance in a model plant, Arabidopsis. Here, we examined whether HA or CAVA enhances the growth of Italian ryegrass seedling. Height and fresh weight of the plant with foliar application of HA or CAVA were bigger than those with only water. Interestingly, enhanced root developments were also observed in spite of the foliar treatments of HA or CAVA. Finally, we proved that HA or CAVA promotes the regrowth of Italian ryegrass after cutting. Collectively, CAVA acts as a HA mimic in Italian ryegrass cultivation, and both as a biostimulant enhanced the early growth and regrowth after cutting of Italian ryegrass, which could improve the productivity of forage crops.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.12
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• pp.1717-1724
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• 2004

The study was conducted to determine the effect of Salmonella typhymurium lipopolysaccharide (LPS) challenge on egg-laying performance, inflammatory response, zinc metabolism in layer fed diets supplemented with organic or inorganic zinc since 3-wk-old. The three dietary treatments were corn-soybean meal basal diet without supplemental zinc or with supplemental zinc at 60 mg/kg zinc from $ZnSO_4$ or zinc amino acid complex (ZnAA). At the age of 58 wk-old, twelve hens from each dietary treatment were allotted into two sub-groups. On day 1, 3, 5, 7 of the $58^{th}$ week of age, six birds of one sub-group were injected intraperitoneally (i.p.) with 2 ml LPS (1.0 $\ell$/ml) or sterile saline. Neither zinc source ${\times}$ immune challenge interaction nor zinc source effect on egg production performance was observed (p>0.05), LPS-challenge decreased egg production (p<0.04) and increased percentage of cracked eggs (p <0.01). With LPS challenged, the fever response of hens fed ZnAA peaked and subsided earlier than in hens fed $ZnSO_4$ or basal diet. Serum IL-1$\beta$ at 3 h was higher (p<0.01), but lower (p<0.001) at 12 h post-challenge with LPS in hens fed ZnAA than $ZnSO_4$. In salinetreated groups, serum IL 1$\beta$ was higher in hens fed ZnAA than the basal diet at 3 h post-injection (p<0.01). LPS-challenged birds had lower serum zinc and higher zinc sequestered in liver and spleen (p<0.001). In saline-treated birds, there was no difference in zinc concentration of serum, liver and spleen among different dietary treatments (p>0.05). Supplementation of 60 mg/kg zinc from either ZnAA or $ZnSO_4$ significantly (p<0.05) elevated metallothionein (MT) concentration in liver and spleen. MT concentration in liver of birds fed ZnAA diet was higher than in those fed $ZnSO_4$ diet (p<0.05). The magnitude of increase of hepatic and splenic MT due to LPS challenge was higher by supplementation of ZnAA than $ZnSO_4$. The results suggest that zinc amino acid complex enhanceed MT synthesis and zinc sequestered in liver and spleen and increased the sensitivity to immune response due to LPS challenge.

• Journal of the Korean institute of surface engineering
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• v.43 no.6
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• pp.297-303
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• 2010

The effect of solution acidity and organic additives, polyethylene glycol (PEG), on the trivalent chromium electroplating was systematically investigated in the view point of electroreduction of trivalent chromium ions and solution stability. It was found that solution acidity controlled at pH 2.5 showed the widest current range for bright electrodeposits in the presence of PEG additives, which reduced the local current intensification at high current densities. Through complex interaction between PEG additives and hydrogen ion, that is, solution acidity, electrode potential was moved in the negative direction in the bulk solution, while it shifted in the positive when electric potential was scanned. In conjunction with electrochemical quartz crystal microbalance (EQCM), it was found that PEG additives had a role in promoting the electron transfer to trivalent chromium ion complexes in bulk solution and their adsorption at the electrode surface as well as interfering with hydrogen ion reduction process below pH 2.5. The PEG additives developed the nodular morphology during electroreduction of trivalent chromium ions with the increase of solution acidity and enhanced its current efficiency by maintaining the consumption of complexant, formic acid, at low speed.

• Preventive Nutrition and Food Science
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• v.6 no.1
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• pp.6-9
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• 2001

Minimal inhibitory concentrations (MIC) and antimicrobial effects of glycerol monolaurate (monolaurin) and organic acids, either alone or in combination, against Escherichia coli O157:H7 in tryptic soy broth were determined. MIC values of monolaurin(ML), acetic (AA), citric (CA), lactic (LA) and hydrochloric acid (HCl) were 300$\mu\textrm{g}$/mL (0.03%), 1250$\mu\textrm{g}$/mL(0.125%), 5000$\mu\textrm{g}$/mL(0.5%), 2500$\mu\textrm{g}$/mL(0.25%) and 2500$\mu\textrm{g}$/mL(0.25), respectively. When 150$\mu\textrm{g}$/mL of ML was combined with 50$\mu\textrm{g}$/mL AA, 250$\mu\textrm{g}$/mL HCl and 125$\mu\textrm{g}$/mL LA, the combined agents did not increase the inhibitory effect of the most active single compound alone. This result indicates that there was little interaction between ML and A, HCl and LA. However, the combination of 150$\mu\textrm{g}$/mL ML and 250$\mu\textrm{g}$/mL CA synergistically inhibited growth of E. coli O157:H7. The present study showed that the nature of combined antimicrobial response against E. coli O157:H7 was complex, but this information would be useful for determining interaction that could compromise effectiveness in food systems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.756-762
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• 2014

This study evaluated the quality characteristics of soybean fermented with several Bacillus sp., which were selected based on their high enzymatic and antimicrobial activities. Total aerobic bacterial counts of fermented soybeans with HJ5-2 ($3.00{\times}10^9CFU/mL$) were the highest among all strains. Lactic acid bacteria numbered $2.50{\times}10^2{\sim}7.30{\times}10^4CFU/mL$ in soybeans fermented with isolates. Amylase and protease activities of the RD7-7 sample were the highest among all strains. Reducing sugar and amino-type nitrogen contents of fermented soybeans with HJ18-4 (2.35%) and RD7-7 (227.96 mg%) were the highest. Total amino acid contents of the samples were 16.62~18.38%, and glutamic acid, aspartic acid, leucine, lysine, arginine were major amino acids. Oxalic acid (36.51~63.57 mg/100 g) and succinic acid (429.49~600.15 mg/100 g) were the predominant organic acid. These results provide useful information for development starter (single and complex) as well as for the production of high quality fermented soybean foods.

• Food Science and Preservation
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• v.24 no.2
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• pp.187-195
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• 2017

This study evaluated quality characteristics of soybean fermented by selected lactic acid bacteria, which were the enzyme strains with high antimicrobial activities isolated from traditionally prepared soybean paste. We determined total aerobic and lactic acid bacteria counts, protease and amylase activities, reducing sugar and amino-type nitrogen contents, and the amounts of amino acids, organic acids, and aroma-compounds. The total aerobic bacteria counts in soybean fermented with strain I13 ($7.75{\times}10^9CFU/mL$) were the highest among all the strains analyzed. Lactic acid bacteria numbers were $2.85{\times}10^9$ to $4.35{\times}10^9CFU/mL$ in soybean fermented with isolates. Amylase and protease activities of the JSB22 sample were the highest among all sample. Reducing sugar and amino-type nitrogen contents of soybean fermented with JSB22 (1.23%, 94.52 mg%) were highest. Total amino acid content of the samples was 15.88-17.62%, and glutamic acid, aspartic acid, leucine, lysine, and arginine were the major amino acids. Lactic acid (0.82-3.65 g/100 g), oxalic acid (22.74-63.57 mg/100 g), and fumaric acid (2.88-6.33 mg/100 g) were predominant organic acids. A total of 39 volatile aroma-compounds were identified, including 2 esters, 5 ketones, 7 alcohols, 14 hydrocarbons, 2 heterocyclic compounds, 4 acids, and 5 miscellaneous compounds. These results represent useful information for the development of a starter (single or complex) and will be used for production of functional fermented soybean foods.

• Journal of Soil and Groundwater Environment
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• v.18 no.7
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• pp.81-89
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• 2013

Concerns have been raised over the impact of nano materials on soil and groundwater environment with the increasing attention to the potential applications of carbon nano materials in various fields. Particularly, carbon nano materials introduced into water environment readily make complexes with humic acid (HA) due to their hydrophobic nature, so there have been increasing numbers of studies on the interaction between HA and carbon nano materials. In this study, we investigated the solubility of HA and multiwalled carbon nanotubes (MWCNT) in three different surfactant solutions of sodium dodecyl sulfate (SDS), Brij 30 and Triton X-100, and evaluated whether the HA can be effectively desorbed from the surface of MWCNT by surfactant. The objective of this study was to determine the optimal adsorption condition for HA to MWCNT. Futhermore, sodium dodecyl sulfate (SDS), Brij 30, Triton X-100 were used to elucidate the effect of desorption and separation on adsorbed HA on MWCNT. As a result, HA solution with 12.7 mg of total organic carbon (TOC) and 5 mg of MWCNT showed the highest adsorption capacity at pH 3 reacted for 72 hrs. Weight solubilizing ratio (WSR) of surfactants on HA and MWCNT was calculated. HA had approximately 2 times lower adsorption capacity for the applied three surfactants compared to those of MWCNT, implying that the desorption of HA may occur from the HA/MWCNT complex. According to the results of adsorption isotherm and weight solubilizing ratio (WSR), the most effective surfactants was the SDS 1% soluiton, showing 53.63% desorption of HA at pH 3.