• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.758-761
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• 2009

The electroluminescent devices with the phenylnaphthyldiamine HTMs as the hole-transporting layer were more efficient than that with the biphenyldiamine HTM 1. Particularly, the life-time of the device IV using HTM 2 is about two times longer than that of the reference device III with HTM 1 within the measured current density, indicating more effective recombination at the emitting layer of device IV.

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.106-110
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• 2006

Photocatalytic electron transfer reactions of aryl benzyl sulfides using 2,4,6 triphenylpyrilium tetrafluoroborate ($TP^+BF_4^-$) resulted in the oxidation of these sulfides to the corresponding sulfoxides and also in most cases in the C-S bond cleavage of them along with formation of aromatic aldehydes. In these reactions, the formation of sulfide radical cation has been proposed, which undergoes either oxidation to the corresponding sulfoxide or C-S bond cleavage to the formation of aromatic aldehydes. The further oxidation of sulfoxides to sulfones has not been observed. The influence of substrate structures on the reaction pathways as well as the role of $O_2$ in this respect is discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.6
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• pp.652-660
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• 2004

The cis-hex-3-ene-1,5-diynyl-bridged diiron compound 3, [(η$^{5}$ - $C_{5}$ M $e_{5}$ ) Fe(dppe)］$_2$($\mu$-C≡C-CH=CH-C≡C), have been prepared and characterized by cyclic voltammetry(CV), and electronic spectroscopy (UV-VIS and near-IR, NMR). From the results, compound 3 show two well resolved, single-electron, reversible oxidation waves by CV, and comproportionation constant(Kc) calculated from the CV data for compound 3. The Mixed-valence (MV) radical cation 3$^{+}$ show strong absorptions in the near IR, 1586 nm, and this band is more readily assigned as MV $\pi$-$\pi$ band of delocalized complex (Robin-Day Mixed-valence Class III), and the $H_{ab}$ , effective coupling parameter are most consistent with electronic delocalization.

• Journal of Photoscience
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• v.6 no.3
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• pp.117-121
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• 1999

Photoinduced electron transfer of C60 has been studied by the laser photolysis measuring the transient absorption bands in near-IR region. The electron transfer aromatic amines via the triplet state of C60 is confirmed by the decay of the transient absorption bands of the triplet state of C60 and the rise of the anion radical of C60 and the cation radicals of amines. The rate and efficiency of electron transfer are strongly affected by the donor ability of amines and polarity of solvents. Back electron-transfer kinetics is also strongly affected by the solvent polarity.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.271-279
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• 2017

This study evaluated antimicrobial efficacy and antioxidant effect of fraction isolated from Coptis Radix and confirmed its possibility as a cosmetic material. The extracts of isolated from Coptis Radix conducted an antimicrobial activity against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Candida albicans by disc diffusion method and measure clear zone. As a result, it was confirmed that antimicrobial activity against S. aureus and candida. A was observed in all samples except Fr 1. The activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and The activity of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) cation radical scavenging were determined by antioxidant assay according to the concentrations (50, 125, 250) ${\mu}g/mL$ of extracts of isolated from Coptis Radix. As a result, DPPH radical scavenging activity of Fr 1, 2, 3, 4 at $250{\mu}g/mL$ was 11.4%, 30.3%, 42.0% and 53.1%, respectively and $ABTS^+$ radical scavenging activity was 28.6%, 96.2%, 98.6% and 97.1% at the same concentration, respectively. Fr. 3 and 4 showed higher radical scavenging activity than the positive the control group BHT at the same concentration. In the WST assay results of measuring the cytotoxicity of Coptis Radix, except for Fr. 4, Fr. 1, 2 and 3 did not show toxicity. As a result, the fractions isolated from Coptis Radix can be regarded as a cosmetic material having antimicrobial activity and antioxidant ability.

• Journal of Mushroom
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• v.16 no.1
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• pp.22-30
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• 2018

This study was performed to determine optimal extraction conditions of fermented Polygonum multiflorum root by Lentinula edodes (JMI10079) Pegler mycelials using response surface methodology. The independent factors were extraction temperature (X1: $40-100^{\circ}C$), extraction time (X2: 2-10 hrs.), and the ratio of water to sample (X3: 33-100 mg/mL). Their effects were assessed on dependent variables of the extract properties, which included soluble solid contents (Y1), $^{\circ}Brix$ of sample extract (Y2), total polyphenol content (Y3), total flavonoid content (Y4), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical cation scavenging activity (Y5) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (Y6). The experimental data obtained were fit to a second-order polynomial equation. The optimal extraction conditions for fermented P. multiflorum root were: X1: $91.22^{\circ}C$, X2: 7.72 hrs, and X3: 39.71 mg/mL.

• Journal of Life Science
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• v.22 no.7
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• pp.943-949
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• 2012

The content phenolic compounds in extracts from Rehmannia glutinosa was the highest in 40% ethanol extracts as $5.1{\pm}0.2mg/g$. DPPH scavenging activity of R. glutinosa extracts was high in water extracts and 40% ethanol extracts as 85~93%, ABTS radical cation decolorization of water extracts and 40% ethanol extracts was about the same as 55~62%, antioxidant protection factor (PF) was confirmed in water extracts and 40% ethanol extracts as 1.6~1.9 PF, and TBARs of water extracts and 40% ethanol extracts were concluded to have the similar antioxidant effects. The hypertension inhibitory activity of water extracts and 40% ethanol extracts from R. glutinosa indicated the activities as 87.2% and 81.1%, anti-gout activity was determined very low in R. glutinosa extracts and antimicrobial activity against skin microorgasm was confirmed, and tyrosinase inhibitory activity was determined as 70.2% in 40% ethanol extracts, it was expected the whitening effects in 40% ethanol extracts. The elastase inhibitory activity which are related to the wrinkle cause was observed in water extracts and 40% ethanol extracts as 76.2% and 57.2%. The hyaluronidase inhibitory activity to R. glutinosa extracts was observed weakly in only 40% ethanol extracts of $200{\mu}g/ml$ phenolic content as 5.1%.

• Journal of Oriental Neuropsychiatry
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• v.20 no.1
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• pp.1-19
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• 2009

Objectives : This Study was performed to assess the antioxidative and neuroprotective effect of Guibi-tang(Guipi-tang) and Guibi-tang gamibang(Guipitang jiaweifang) on PC12 cells. Methods : The antioxidative effect was investigated through the DPPH radical and ABTS cation scavenging methods and total polyphenol amount of Guibi-tang(Guipitang) and Guibi-tang gamibang(Guipitang jiaweifang). The neuroprotective effect of Guibi-tang(Guipitang) and Guibi-tang gamibang(Guipitang jiaweifang) was assessed using MTT assay in PC12 cells. The scavenging effect of Guibi-tang(Guipitang) and Guibi-tang gamibang(Guipitang jiaweifang) on NO and ROS production induced by 6-OHDA in PC12 cells was evaluated, as well as the attenuating effect of Guibi-tang gamibang(Guipitang jiaweifang) on GSH reduction. Results : 1. Guibi-tang(Guipitang) and Guibi-tang gamibang(Guipitang jiaweifang) had concentration-dependent scavenging activities of DPPH radical 2. Guibi-tang(Guipitang) and Guibi-tang gamibang(Guipitang jiaweifang) had concentration-dependent scavenging activities of ABTS cation. 3. Total polyphenol amount of Guibi-tang(Guipitang) and Guibi-tang gamibang(Guipitang jiaweifang) was calculated 79.10${\pm}$2.20 pg/IO mg and 121.03${\pm}$1.11 pg/IO mg, respectively. 4. Cell viability of Guibi-tang(Guipitang) was increased in a dose dependent manner. Guibi-tang gamibang(Guipitang jiaweifang) was increased at low concentrations, but decreased at high concentrations. 5. In Guibi-tang(Guipitang), cell viability of PC12 cell treated with 6-OHDA was decreased by pre-treatment, and increased by post- and co- treatment. Cell viability of Guibi-tang gamibang(Guipitang jiaweifang) showed variable effects by pre-treatment, but increased by post- and co- treatment. 6. NO production rate of Guibi-tang(Guipitang) didn't show a significant effect, but that of Guibi-tang gamibang(Guipitang jiaweifang) was decreased in a dose dependent manner. 7. ROS production rate of Guibi-tang(Guipitang) was decreased at some concentrations. In Guibi-tang gamibang(Guipitang jiaweifang), ROS production rate was decreased at high concentrations. 8. Guibi-tang gamibang(Guipitang jiaweifang) protected the 6-OHDA-induced GSH reduction. Conclusions : These results demonstrate that both Guibi-tang(Guipitang) and GBTGMB have antioxidative and neuroprotective effect, but Guibi-tang gamibang(Guipitang jiaweifang) has more antioxidative and neuroprotective effect than Guibi-tang.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.397-402
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• 2015

This study was carried out to analyze the nutritional composition, bioactive compound and antioxidant activity in fresh sprout of 3 new Kalopanax septemlobus cultivars. Cheong-San, Cheong-Song and Cheong Sun 1 had largest carbohydrate (52.90, 53.12, 55.28%), crude protein (34.23, 31.33, 33.58%) in the proximate composition and had largest K (2.29, 2.22, 2.23%) followed by Ca (0.44, 0.34, 0.37%), Mg (0.24, 0.19, 0.19%) in the mineral contents. Three new cultivars contained a total of 26, 25 and 28 different kinds of amino acids, respectively and the number of essential amino acid is 6, 6 and 7 species, respectively. Also, Cheong-San had higher total polyphenol contents and Cheong-Song had higher total flavonoid contents. DPPH free radical scavenging activity of 70% ethanol, water extracts of Cheong-San and Cheong-Song is higher than others at 100 ppm. In the ABTS radical cation decolorization activity, 70% ethanol extract of Cheong Sun 1, water extract of Cheong-San and Cheong-Song are higher activity than others and all samples have more than 85% ABTS racial cation decolorization activity at 500 ppm. Our results suggest that new K. septemlobus cultivars possess good antioxidant capacities with a high nutritional value and might have potential applications in the food and medical industries.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.478-483
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• 2014

To develop tofu with bioactivity, red ginseng extract was added and soft tofu was prepared without pressuring and forming steps. Then, the content of antioxidant components and antioxidative activities were measured using the prepared soft tofu during storage. The contents of polyphenols of the control and the sample added red ginseng extract were $605.25{\mu}g/mL$ and $598.51{\sim}681.65{\mu}g/mL$. The content of the polyphenols was proportional to the concentration of added red ginseng extract. The content of ascorbic acid of the control was 6.42 mg%, and the ascorbic acid contents of the sample added red ginseng extract were higher than that of the control. The contents of polyphenols and ascorbic acid of control were lower than those of the sample added red ginseng extract during the storage. The addition of red ginseng extract increased reducing power and ABTS radical cation decolorization.