• Korean Journal of Environmental Agriculture
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• v.10 no.2
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• pp.128-132
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• 1991

This study was carried out to find a method to remove cadmium from soil and/or attenuate in Cd saturated Soil The chemical form of Cd was influenced by the physico-chemical properties of soil and the adsorption of Cd by soil conformed to the Langmuir isotherm. The order of Cd contents in chemical fractions extracted by several reagents was EDTA > NaOH > $HNO_3$. Flooding, liming and the addition of chelating agents and clay minerals to the contaminated soil seems to desirable in alleviating the harmful effects of Cd on plant growth by reducing Cd content in the $KNO_3$ fraction.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.147-155
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• 1999

Antioxidant effects of serotonin and L-DOPA on neuronal tissues were examined by studying the oxidative damages of brain synaptosomal components. The study further explored the mechanism by which they exert protective actions. Serotonin and L-DOPA (1 ${\mu}M$ to 1 mM) significantly inhibited lipid peroxidation of brain tissues by either $Fe^{2+}$ and ascorbate or t-butyl hydroperoxide in a dose dependent fashion. Protective effect of serotonin on the peroxidative actions of both systems was greater than that of L-DOPA. Protein oxidation of synaptosomes caused by $Fe^{2+}$ and ascorbate was attenuated by serotonin and L-DOPA. Protein oxidation more sensitively responded to L-DOPA rather than serotonin. Serotonin and L-DOPA (100 ${\mu}M$) decreased effectively the oxidation of synaptosomal sulfhydryl groups caused by $Fe^{2+}$ and ascorbate. The production of hydroxyl radical caused by either $Fe^{3+},$ EDTA, H_2O_2$ and ascorbate or xanthine and xanthine oxidase was significantly decreased by serotonin and L-DOPA (1 mM). Equal concentrations of serotonin and L-DOPA restored synaptosomal $Ca^{2+}$ uptake decreased by $Fe^{2+}$ and ascorbate, which is responsible for SOD and catalase. Protective effects of serotonin and L-DOPA on brain synaptosomes may be attributed to their removing action on reactive oxidants, hydroxyl radicals and probably iron-oxygen complex, without chelating action on iron.

• Progress in Superconductivity
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• v.8 no.1
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• pp.59-64
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• 2006

High $J_c\;YBa_2Cu_3O_x$ superconducting films were fabricated by MOD method using fluorine-free dichloroacetic acid(DCA) as chelating solvent for preparing precursor solution. Coating solutions were prepared by dissolving Y-, Ba- and Cu-acetates in DCA solvent followed by drying in rota vapor to obtain the blue gel that is diluted in methanol and 2-methoxyethanol for adjusting the cation concentration. DCA-MOD precursor solution was coated on a single crystal(001) $LaAlO_3(LAO)$ substrate by a dip coating method with a speed of 25 mm/min. Coated films were calcined at lower temperature up to $500^{\circ}C$ in flowing oxygen atmosphere with a 7.2% humidity. Conversion heat treatment was performed at various temperatures of $780{\sim}810^{\circ}C$ for 2 h in flowing Ar gas containing 1000 ppm oxygen with a humidity of 9.45%. SEM observations showed that films have very dense microstructures for the films prepared at the temperature higher than $800^{\circ}C$ regardless of diluting solvent; methanol or 2-methoxyethanol. X-ray diffraction analysis showed that YBCO grains grew with a (001) preferred orientation. A High critical current density($J_c$) of 1.28 $MA/cm^2$(@77 K and self-field) was obtained id. the YBCO film prepared using 2-methoxyethanol as a solvent.

• Progress in Superconductivity
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• v.8 no.2
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• pp.186-192
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• 2007

High $J_c\;YBa_2Cu_3O_{7-x}$ superconducting films have been fabricated $LaAlO_3(100)$ substrate by MOD method using dichloroacetic acid(DCA) as chelating solvent for preparing precursor solution. Heating rate was varied in order to optimize the calcination heat treatment condition in DCA-MOD method. Coated films were calcined at lower temperature up to $500^{\circ}C$ in flowing humid oxygen atmosphere. The heating rate was calcined from $13.3^{\circ}C/min\;to\;0.28^{\circ}C/min$. Conversion heat treatment was performed $800^{\circ}C$ for 2 h in flowing Ar gas containing 1000 ppm oxygen with a humidity of 9.45%. Surface and cross sectional SEM microstructures showed that particle sizes were increased with heating rate at a calcination step. The amount of pores was increased with heating rate in the calcined films. Dense microstructure and sharp texture were developed in an YBCO films after conversion heat treatment. A high critical current density (Jc) of $1.26MA/cm^2$ (@77 K and self-field) was obtained for the YBCO film which was prepared with a heating rate of $0.28^{\circ}C/min$.

• Natural Product Sciences
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• v.21 no.3
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• pp.210-218
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• 2015

The antioxidant activity of white ginseng was not recorded in Korea Functional Food Code, while its activity of red ginsengs was recorded. The aim of this study was to evaluate the antioxidant and hepato protective effect of different ginsengs in H₂O₂-treated HepG2 cells. White and red ginseng were prepared from longitudinal section of the same fresh ginseng (4-year old). The whole parts of white and red ginsengs were separately extracted with 70% ethanol and distilled water respectively, at 70 ℃ to obtain therapeutic ginseng extracts namely, WDH (distilled water extract of white ginseng), WEH (70% ethanol extract of white ginseng), RDH (distilled water extract of red ginseng) and REH (70% ethanol extract of red ginseng). In this work, we have investigated the DPPH, hydroxyl radical, Fe²⁺-chelating activity, intracellular ROS scavenging capacity and lipid peroxidation of different ginsengs. All these extracts showed a dose dependent free-radical scavenging capacity and a ROS generation as well as lipid peroxidation was significantly reduced by treatment with bioactive extracts of white ginsengs (WDH) than red ginsengs. Additionally, white ginseng extracts (WDH) has dramatically increased intracellular antioxidant enzyme activities like superoxide dismutase and catalase in H₂O₂-treated HepG2 cells. All these results explain that administration of white ginseng is useful as herbal medicine than red ginseng for chemoprevention of liver damage.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.3
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• pp.20-27
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• 2014

Nowadays, the bleaching techniques of thermomechanical pulp(TMP) are fast developing on the strength of some benefits, mainly on low production cost and good fiber property. In this study, the optimum concentration of bleaching chemicals and the environmental load of bleaching wastes were considered to improve the bleaching efficiency of thermomechanical pulp using Korean redpine(Pinus densiflora) under the peroxide-based bleaching system. The optical property of TMP after bleaching was planned to use higher grade of paper, like printing & writting paper, not general newspaper. The concentration of bleaching chemicals, NaOH, $Na_2SiO_3$ and EDTA, in hydrogen peroxide bleaching system, on the basis of O.D. pulp was closely influenced on the improvement of TMP brightness. Final target of bleaching efficiency was set up to above 76%-ISO brightness. The optimal target brightness of Korean redpine TMP was reached to 76.45%-ISO under the conditions of $H_2O_2$ 7% with NaOH 2.20%, $Na_2SiO_3$ 0.63% and EDTA 0.02%. The concentration of NaOH, $Na_2SiO_3$ and EDTA was correlated functional to the residual peroxide content of wastewater, pH value and electric conductivity of TMP fibers after bleaching treatment. The optimal bleaching conditions by controlling the addition amount of chemicals were positively contributed to the brightness stabilization and environmental load of TMP.

• Journal of Life Science
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• v.11 no.6
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• pp.543-553
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• 2001

Lead poisoning is currently one of the major public health problems in industrialized countries. Several chelating agents have been developed and used to treat the lead poisoning. It was recently proposed that garlic, having a large quantity of S-S compounds, may react readily with lead, producing various sulfur componds, and thus provide curative and protective effects on the lead toxicity. The present study was undertaken to evaluate this possibility in experimental animals. The garlic treatment on rats pre-exposed to lead significantly enhanced urinary excretion of lead at a garlic dose of 500 mg/kg and decreased the bloon level of lead at both 250 and 500 mg/kg doses. The administration of grilic 500mg/kg along with lead significantly alleviated the renal histological alterations induced by lead. These results suggest that garilic has a curative as well as a protective effect against lead poisoning , thus it may act as a chelator of lead.

• Korean journal of food and cookery science
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• v.28 no.3
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• pp.319-326
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• 2012

This study was designed to investigate the properties related to browning of hot water and 80% ethanol extracts of green tea (Camellia sinensis) and propolis. The extracts were assessed for polyphenol oxidase (PPO) inhibitory activity and total phenolic and flavonoid contents. In addition, apples were cut into 15 mm thick slices and dipped for 1 min in 0.5% of the green tea extracts and the propolis solutions and stored at room temperature for 24 h. The PPO inhibitory activity of the green tea extracts was better than that of the propolis. The highest DPPH free radical scavenging activity (90.81%), total phenol contents (170.42 mg/mL) and the metal chelating effects (45.93%) were measured in the green tea hot water extracts. The mineral content of the green tea water extracts was 69,328.44 ppm potassium and 2,409.42 ppm magnesium. After 24 h, the ${\Delta}E$ value of the apple slices treated with the green tea water extracts was the lowest (1.35). The antibrowning effects of the green tea extracts were higher than those of propolis in the apple slices.

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.246-251
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• 2010

This study was conducted to investigate the quality characteristics of guavapyun after the addition of different ratios of extract (0.25, 0.5, 0.75, 1.0%), non-extract and vitamin C. The quality if the pyun containing 0.5% of the guava fruit extract (guavapyun) and vitamin C was higher compared with the quality of the control pyun. In the results of the proximatecomposition, the content of water was high in the control pyun relative to the vitamin C pyun and guavapyun and the carbohydrate, ash, crude lipid and protein content was high in guavapyun. The sweetness, pH and color (L, a, b value) were very high in the samples. The texture, hardness, chewiness and gumminess were significantly high in the control pyun and the adhesiveness and cohesiveness were high in guavapyun. However, there were no significant differences in springiness between the control and the added samples. The total phenolic content was higher in guavapyun (23.57 mg GAE/100 g) than the control pyun (18 mg GAE/100 g) and vitamin C pyun(15.05 mg GAE/100 g). The antioxidant activities determined by the DPPH method and ABTS method was higher in guavapyun (41.37 mM TE/g, 15.35 mM TE/g) than the control pyun (4.43 mM TE/g, 2.17mM TE/g) and vitamin C pyun (11.33 mM TE/g, 4.51 mM TE/g). Using the FRAP method, guavapyun(9.06 mM TE/g) was shown to exhibit a stronger ferrous ion chelating activity than the control pyun (4.49mM TE/g) and vitamin C pyun (7.03 mM TE/g). Thus, the studied indigenous guavapyun was high in both antioxidative activity and total phenolic content.

• Korean Journal of Pharmacognosy
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• v.47 no.3
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• pp.204-210
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• 2016

Phytochemical investigation of the 80% MeOH extract from the stems of Lagerstroemia indica resulted in the isolation of eighteen compounds; four norsesquiterpenes, fourteen phenolic derivatives. Their chemical structures were characterized by spectroscopic methods to be tachioside (1), isotachioside (2), 2,4,6-trimethoxyphenyl ${\beta}$-D-glucopyranoside (3), gallic acid 4-methyl ether (4), protocatechuic acid (5), gallic acid (6), vanillic acid (7), vanillin (8), 2-methoxy-5-hydroxymethyl-phenyl-1-O-(6"-galloyl)-${\beta}$-D-glucopyranoside (9), 2,4,6-trimethoxyphenol-1-O-${\beta}$-D-(6'-O-galloyl)-glucopyranoside (10), 4-hydroxy-3-methoxyphenyl-1-O-(6'-O-galloyl)-${\beta}$-D-glucopyranoside (11), vomifoliol (12), vomifoliol 9-O-${\beta}$-D-glucopyranoside (13), 6R,9R-3-oxo-${\alpha}$-ionol-9-O-${\beta}$-D-glucopyranoside (14), dihydrophaseic acid 4'-O-${\beta}$-D-glucopyranoside (15), ${\beta}$-hydroxypropiovanillone 3-O-${\beta}$-D-glucopyranoside (16), myrciaphenone A (17), and coumaric acid (18). Compounds 1-5 and 7-18 were isolated for the first time from this plant. Compounds 1-18 were investigated for their antioxidant properties using DPPH and ABTS radical scavenging capacity assay, $Fe^{2+}$ chelating, and FRAP assay. It was found that 4, 6, and 11 possessed the highest antioxidant capacities.