• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.489-494
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• 2006

Goethite, hematite, magnetite and synthesized iron oxide are used as catalysts for Fenton-type oxidation of phenol. The synthesized iron oxides were characterized by X-ray diffraction (XRD), BET, X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR). The catalytic activity of these materials is classified according to the observed rate of phenol oxidation. The effectiveness of the catalysts followed the sequence: ferrous ion > synthesized iron oxide >> magnetite hematite > goethite. According to these results, the most effective iron oxide catalyst had the structure similar to natural hematite. The surface oxidation state of the catalyst was between magnetite and hematite (+2.5 ~ +3.0). Phenol degraded completely in 40 min at neutral pH (pH = 7). Soluble ferric and ferrous ions were not detected in the filtrate from Fenton reaction solution by AAS. The formation of hydroxyl radicals was confirmed by EPR.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.375-383
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• 2007

Treatment efficiency research was performed using Fenton process and the electrochemical process in the presence of ferrous ion and hydrogen peroxide for the industrial wastewater including 1,4-Dioxane produced during polymerization of polyester. The Fenton process and the electrochemical Iron Redox Reaction (IRR) process were applied for this research to use hydroxyl radical as the powerful oxidant which is continuously produced during the redox reaction with iron ion and hydrogen peroxide. The results of $COD_{Cr}$ and the concentration of 1,4-Dioxane were compared with time interval during the both processes. The rapid removal efficiency was obtained for Fenton process whereas the slow removal efficiency was occurred for the electrochemical IRR process. The removal efficiency of $COD_{Cr}$ for 310 minutes was 84% in the electrochemical IRR process with 1,000 mg/L of iron ion concentration, whereas it was 91% with 2,000 mg/L of iron ion concentration. The lap time to remove all of 1,4-Dioxane, 330 mg/L in the wastewater took 150 minutes with 1,000 mg/L of iron ion concentration, however it took 120 minutes with 2,000 mg/L of iron ion concentration in the electrochemical IRR process.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.3
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• pp.189-195
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• 2013

Amyloid-${\beta}$ peptide ($A{\beta}$), generated by proteolytic cleavage of the amyloid precursor protein (APP), plays a pivotal role in the pathogenesis of Alzheimer's disease (AD). The key step in the generation of $A{\beta}$ is cleavage of APP by beta-site APP-cleaving enzyme 1 (BACE1). Levels of BACE1 are increased in vulnerable regions of the AD brain, but the underlying mechanism is unknown. In the present study, we reported the effects of ferrous ions at subtoxic concentrations on the mRNA levels of BACE1 and a-disintegrin-and-metalloproteinase 10 (ADAM10) in PC12 cells and the cell responses to ferrous ions. The cell survival in PC12 cells significantly decreased with 0 to 0.3 mM $FeCl_2$, with 0.6 mM $FeCl_2$ treatment resulting in significant reductions by about 75%. 4,6-diamidino-2-phenylindole (DAPI) staining showed that the nuclei appeared fragmented in 0.2 and 0.3 mM $FeCl_2$. APP-${\alpha}$-carboxyl terminal fragment (APP-${\alpha}$-CTF) associations with ADAM10 and APP-${\beta}$-CTF with BACE1 were increased. Levels of ADAM10 and BACE1 mRNA increased in response to the concentrations of 0.25 mM, respectively. In addition, p-ERK and p-Bad (S112, S155) expressions were increased, suggesting that APP-CTF formation is related to ADAM10/ BACE1 expression. Levels of Bcl-2 protein were increased, but significant changes were not observed in the expression of Bax. These data suggest that ion-induced enhanced expression of AMDA10/BACE1 could be one of the causes for APP-${\alpha}/{\beta}$-CTF activation.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.79-86
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• 2010

Effects of operating parameters such as applied voltage, solution conductivity, ferrous ion concentration, electrode material on phenol degradation by pulsed corona discharges were investigated in laboratory scale experiments. The increase of applied voltage enhanced the phenol degradation by generating more energetic electrons. The solution conductivity inversely affected phenol removal rate in the tested ranges because the increase of conductivity decreased the electric field strength through the liquid phase. The addition of ferrous sulfate promoted the phenol degradation through the OH radical production by the Fentonlike reactions between ferrous ion and hydrogen peroxide generated by pulsed corona discharges. Catechol and hydroquinone were detected as primary intermediates of phenol degradation and the decrease of pH and the increase of conductivity were observed probably due to the generation of organic acids. Almost all of the initial phenol was disappeared and 29% of total organic corbon (TOC) was removed in the condition of 0.5 mM of ferrous sulfate after approximately 230 kJ of discharge energy transferred to the reactor.

• Korean journal of food and cookery science
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• v.29 no.4
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• pp.407-416
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• 2013

This study was investigated physiological activities of enzyme hydrolysates in 80% ethanol extracts from sesame, black sesame and perilla cake. Total phenol contents in 80% ethanol extracts of sesame, black sesame and perilla cake were 116.90, 102.20 and 141.90 mg/g, respectively. Whereas total flavonoid contents were 64.10, 32.00 and 131.90 mg/g, respectively. Total phenol contents of enzyme hydrolysates in 80% ethanol extracts from sesame, black sesame and perilla cake were 413.30, 221.20 and 409.10 mg/g, respectively. Whereas total flavonoid contents were 361.80, 103.30 and 345.80 mg/g, respectively. Electron donating effects, nitrite-scavenging abilities, ferrous ion chelating effect and SOD-like activities increased by emzymatic hydrolysis. The order of Electron donating effects, nitrite-scavenging abilities and SOD-like activities by emzymatic hydrolysis was perilla > sesame > black sesame cake. And the order of nitrite-scavenging abilities(pH 1.2) was sesame > perilla > black sesame cake.

• Korean Journal of Plant Resources
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• v.22 no.4
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• pp.304-311
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• 2009

This study was conducted to develop functional sprout vegetables with antioxidant effects using seeds of Arctium lappa. The seeds germinated vigorously under light at $25^{\circ}C$, reaching germination rate of 82% within 4 days. Germinated seeds were placed under darkness at various temperatures to force growth in length, and it was demonatrated that $20^{\circ}C$ was optimum temperature. Greening treatment reduced growth in length, but promoted growth of cotyledons. Harvested A. lappa sprout vegetables maintained freshness longer at $10^{\circ}C$, rather than $4^{\circ}C$. Ventilation holes in storage containers had no effects on storage periods. Antioxidant activity of vegetable that received greening treatment for 1-3 days was investigated, and it was shown that free radical scavenging effects and ferrous ion chelating effects was higher than those of commercially available brocoli, cauliflower, pea and bean sprout. Contents of total polyphenol and flavonoid were also higher, especially by 3 day greening. The longer the treatment, the more the inhibition on peroxidation of linoleic acid. Sprout vegetable of A. lappa had higher antioxidant activity compared with adult plant. In conclusion, sprout vegetable of A. lappa has great potentiality for use as one of sprout vegetables.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.2
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• pp.159-164
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• 2010

The present experiments were carried out to develop new antioxidants from EtOH extract of flower resources of Compositae plant concerning total polyphenol and flavonoid content, scavenging activities on DPPH and ABTS radicals, ferrous ion chelating effects, and inhibition activity on lipid peroxidation of linoleic acid. EtOH extracts from Matricaria recutica, Cosmos bipinnatus, Synurus deltoides, and Aster pilosus showed higher level of total polyphenol content, and the flavonoid content was the highest in C. bipinnatus. However, scavenging activity on DPPH radicals was the highest in EtOH extract of Hieracium pilosella-1.1 times higher than BHT control. The activity on ABTS radical scavenging was the highest in EtOH extracts of M. recutica and S. deltoides-2.0 and 1.2 times higher than ascorbic acid, and 2.2 and 1.3 times higher than BHT, respectively. Ferrous ion chelating effects was also the highest in M. recutica, but the level was much lower than EDTA. Inhibition activity on lipid peroxidation of linoleic acid, measured at every 4 days for 32 days, was superior and longer lasting with M. recutica and Achillea alpina, compared to that of BHT. In conclusion, antioxidant activity was different depending on species, so selection of proper plant species for the development of potential antioxidant is very important.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.8
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• pp.1187-1193
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• 2010

To elongate the shelf-life of Angelica keiskei and Brassica loeracea var. acephala vegetable juices, UV irradiation was used and the changes of antioxidant activity and nitrite scavenging ability were investigated. The content of polyphenols of vegetable juices were slightly reduced by UV treatment and/or storage period. The DPPH radical-scavenging activities of the vegetable juices treated by UV were higher than that of control but were not changed during storage. However, $ABTS{\cdot}^+$ reducing activities of the vegetable juices were reduced by UV treatment. The $ABTS{\cdot}^+$ reducing activity of Brassica loeracea var. acephala juice was lower when the flow rate was slower. The ferrous ion chelating effects of Angelica keiskei vegetable juices were reduced by UV treatment. In contrast, the ferrous ion chelating effects of Brassica loeracea var. acephala vegetable juices were not different from those of right after manufacturing. The ferrous ion chelating effects on both vegetable juices increased during storage periods. The inhibitory activity of lipid oxidation was decreased slightly by UV treatment on vegetable juices. The nitrite scavenging ability of Angelica keiskei and Brassica loeracea var. acephala vegetable juices treated by UV irradiation was not different from that of control. The nitrate scavenging abilities of vegetable juices in pH 1.2 were higher than those in pH 3.0 and 4.2.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.271-278
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• 2009

The attempts to develop natural antioxidants have been made with aerial part of 16 Compositae species by analyzing their phenolic compound contents, scavenging activities on 1,l-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals, ferrous ion chelating effects and inhibition effects on peroxidation of linoleic acids. Total polyphenol and flavonoid contents were highest in Matricaria recutica. Scavenging activity on DPPH and ABTS radicals were highest with extracts of Echinacea angustifolia and Serratula coronata var. insularis f. insularis, respectively. Aerial palt extracts of all species showed lower DPPH scavenging activity than ascorbic acid and 2,6-Di-tert-butyl-4-methylphenol (BHT). But Serratula coronata var. insularis f. insularis demonstrated higher ABTS scavenging activity than ascorbic acid and BHT. In Hieracium pilosella, Echinacea angustifolia, Matricaria reculica extracts showed higher ABTS scavenging activity than BHT. Ferrous ion chelating effects was highest with Matricaria recutica extract, but the effects were much lower than ethylenediaminetetraacetic acid (EDTA). The inhibition activity in lipid peroxidation of linoleic acids was highest in Eupatorium japonicum with 90.06% inhibition 4 days after reaction and 40.52% after 24 days. This demonstrated higher inhibition activity and longer lasting than BHT. Aerial part of Matricaria recutica for extraction source, rather than flower, has higher potential for antiox.idant material. In conclusion, development of natural antioxidants in Compositae is possible by studying antioxidant activity of each species.

• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.158-164
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• 2009

Present studies were conducted to investigate the effects of water and 80% ethanol solvent on antioxidant activities of flower extracts of Chrysanthemum frutescens, Coreopsis lanceolata, Matricaria recutica, and Hieracium pilosella. Extraction yields of water extracts ranged 27.15~40.25% and 80% ethanol extracts 24.92~42.84%, respectively. In all species polyphenol and flavonoid contents were higher with 80% ethanol extraction, especially in C. lanceolata. Same results were obtained with scavenging effects on DPPH and ABTS radicals and ferrous ion chelating effects. Scavenging activity of flower extracts on DPPH radicals was highest in H pilosella - higher than that of synthetic antioxidant DHT. Higher scavenging activity on ABTS radicals was observed with M. recutica. Generally Compositae flower extracts exhibited higher scavenging activity on ABTS radicals than DPPH. Scavenging activity on ABTS radicals of M. recutica and P pilosella were superior to those of ascorbic acid and BHT. Ferrous ion chelating effects were much higher with H. pilosella flower extracts by 80% ethanol. Chelating effects of 4 species were much lower than those of EDTA. In conclusion, to develop natural antioxidant from above 4 Compositae species, 80% ethanol is recommended for efficient solvent to obtain maximum antioxidant isolation and activity.