• The Korean Journal of Food And Nutrition
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• v.29 no.6
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• pp.946-951
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• 2016

In this study, Ilex serrata Thunb was extracted with 70% methanol and concentrated under reduced pressure to measure its total polyphenol contents; furthermore, we examined the effect of electron donating ability of the various extracts. The extract was fractionated using different solvents such as methylene chloride, ethyl acetate, and methanol to investigate total polyphenol contents and electron donating abilities. The total polyphenol contents were $1,058.59{\pm}85.85{\mu}g\;GAE/mL$ in 70% methanol, $297.29{\pm}29.43{\mu}g\;GAE/mL$ in methylene chloride, $313.28{\pm}9.22{\mu}g\;GAE/mL$ in ethyl acetate, and $837.82{\pm}31.16{\mu}g\;GAE/mL$ in methanol. The total polyphenol contents showed significant differences (p<0.05) between the solvents. The electron donating abilities were $72.93{\pm}0.29%$ for 70% methanol extract, $14.02{\pm}2.01%$ for methylene chloride, $24.05{\pm}1.75%$ for ethyl acetate, and $84.08{\pm}1.95%$ for methanol. The electron donating abilities were significantly different (p<0.05) between the solvents. The two portions of Ilex serrata Thunb extracts obtained from methanol showed significantly relevant results in the total polyphenol contents and electron donating ability, which was higher than the original extract.

• The Korean Journal of Food And Nutrition
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• v.34 no.5
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• pp.537-544
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• 2021

In this study, antioxidative activities of Jeolpyun containing Smilacis chinae R. extract powder (2%, 4%, 6%, 8%) were evaluated using total polyphenol contents, electron donating ability on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and decomposing ability of hydrogen peroxide. In chromaticity analysis, the brightness significantly decreased with increasing Smilacis chinae R. extract powder content. Jeolpyun containing 6% Smilacis chinae R. extract powder revealed the highest value (9.67±0.603) for the redness and 2% Smilacis chinae R. extract powder was the highest value (14.20±0.917) for the yellowness. Total polyphenol contents of Jeolpyun containing 8% Smilacis chinae R. extract powder were the highest content of 17,320±390.38 ㎍ gallic acid equivalent/mL (GAE/mL). Total polyphenol contents were significant relation at p<0.05. Electron donating ability for Jeolpyun containing 8% Smilacis chinae R. extract powder revealed the highest electron donating ability (74.24±0.827%). Electron donating abilities revealed significant difference (p<0.05). Jeolpyun containing 6% Smilacis chinae R. extract powder revealed the most hydrogen peroxide decomposing ability (-3.38±1.44) and hydrogen peroxide decomposing ability revealed significant difference (p<0.05).

• Proceedings of the EASDL Conference
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• 2003.04a
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• pp.83-83
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• 2003

Electron donating ability by DPPH and nitrite scavenge were measured in ethanol extracts from raw, simple cooked and seasoned materials of Bibimbab(mixed rice), Korean traditional one-dish meal. Ethanol extracts of raw frugrantedible wild aster showed the highest electron donating abilities(80.28%) by DPPH. When its seasoned materials were compared with raw and simple cooked materials, it showed the highest electron donating abilities by DPPH.(중략)

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.5
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• pp.1087-1091
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• 1999

Microwave extraction system equipped with closed vessels, which is known to rapidly extract target compounds from natural products, was applied to monitor the changes in phenolic compounds, browning color intensity and electron donating ability by using response surface methodology(RSM). Maximum content of phenolic compound was 21.65mg/100ml in 67.88% of ethanol concentration, 145oC of extraction temperature, and 6.24min of extraction time. The phenolic compounds in extracts are dependent on the increase of the extraction temperature and the ethanol concentration. Browning color intensity, which was maximized in 67.21%, 147oC, and 6.02min, was proportional to the increase of the extraction temperature. Maximum value of electron donating ability was 24.50units in 54.33%, 147oC, and 6.11 min. The electron donating ability of extracts was dependent on the increase of extraction temperature and maximized in the range from 50 to 65% of ethanol concentration.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.1-9
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• 2000

This experiment was accomplished to investigate antioxidative activity of Korean mistletoe by organic solvents partitioning of methanol extact of 3 Korean mistletoes, fractionationing on column chromatography, and evaluation the reduction of a free radical ${\alpha}$,${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl. Butanol partition of Loranthus yadoriki MeOH extract showed higher electron donating ability than ${\alpha}$-tocopherol. It was thought phenolic compounds including gallic acid account for antioxidative activity, on execution sub-fractionation, electron donating ability evaluation, and GC/MS analysis, but further studies on what are major actives must be investigated exactly.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.581-585
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• 1999

The antioxidative activity measured by electron donating ability was investigated for the breeding of the highest antioxidative waxy corn (Zea mays L.) and the research for the most effective antioxidant in waxy corn. The electron donating ability was $15.5{\sim}65.0%$. The contents of phenolic compounds and tocopherols and the absorbance at 450 nm were $102.3{\sim}323.5\;{\mu}g/mL$, $15.6{\sim}144.2\;{\mu}g/mL$ and $0.047{\sim}0.206$, respectively. The mean values of electron donating ability and contents of phenolic compounds and tocopherols of four black waxy corn were comparatively high, that is, 48.7%, $267.0\;{\mu}g/mL$ and $87.0\;{\mu}g/mL$, respectively. The electron donating ability was significantly correlated with the level of phenolic compounds and tocopherols but not with the content of carotenoids.

• Journal of Photoscience
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• v.11 no.1
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• pp.7-9
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• 2004

The synthesized macrocycle L was found to be a smart fluorescent receptor which distinguishable efficiently from various neutral molecules with the functional groups such as the electron donating (X =$CH_3$, N($CH_3$)$_2$ and O$CH_3$) and electron withdrawing groups (X =F and Cl), respectively. In the case of guest molecules containing electron donating groups, the fluorescence of macrocycle L was enhanced in the presence of the guest molecules. On the contrary, in the case of guest molecules containing electron withdrawing groups, it was almost quenched in the presence of those.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.165-171
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• 2017

Diels-Alder 반응은 고리형 탄소화합물을 만드는 유기 합성 과정에서 매우 중요한 반응이다. 이 반응은 중간생성물 없이 오직 1 step으로 진행되는데, diene이나 dienophile에 결합한 치환기의 electron donating 및 electron withdrawing 성질에 따라 반응성이 달라진다고 알려져 있다. 이 때 반응물인 diene과 dienophile의 분자 오비탈 및 전이 상태의 에너지 변화를 계산화학을 통해 분석한다면 Diels-Alder 반응을 보다 심도 있게 이해할 수 있다. 이에 따라 본 연구에서는 DFT 계산을 통하여 치환기에 따른 활성화 에너지의 크기와 diene의 nucleophilicity 및 dienophile의 electrophilicity를 비교하였다. 이를 통해 electron withdrawing group의 경우 분자의 electrophilicity를 증가시키고, electron donating group의 경우 nucleophilicity를 증가시킨다는 것을 확인할 수 있었다. 그 결과, Diels-Alder 반응이 일어날 때 dienophile의 경우 치환된 electron withdrawing group에 의해 electrophilicity가 증가함에 따라 활성화 에너지가 낮아져 반응이 잘 일어나고, 반대로 diene의 경우 electron donating group이 치환되어 있을 때 nucleophilicity의 증가에 따라 반응이 잘 일어난다는 것을 알 수 있었다.

• Macromolecular Research
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• v.15 no.3
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• pp.216-220
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• 2007

A new polyfluorene-based copolymer having 2-ethylhexyloxy-5-methoxy-l,4-phenylene as an electron donating group and 2,5-diphenyl-oxadiazole as an electron withdrawing group was synthesized by the Suzuki coupling reaction. The obtained copolymer was characterized by $^1H-NMR,\;^{13}C-NMR$, and IR-spectroscopy. The weight average molecular weight ($M_w$) of the obtained polymer was 18,600 with a polydispersity index of 1.5. The maximum photoluminescence of the solution and film of the polymer was observed at 453 nm and 456 nm, respectively. A double-layer device with the configuration, ITO/PEDOT/copolymer/Al, emitted blue light at 460 nm.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.857-862
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• 2011

Kinetic studies of the reactions of N-methyl-Y-${\alpha}$-bromoacetanilides with substituted X-benzylamines have been carried out in dimethyl sulfoxide at $25.0^{\circ}C$. The Hammett plots for substituent X variations in the nucleophiles (log $k_N$ vs ${\sigma}_X$) are slightly biphasic concave upwards/downwards, while the Bronsted plots (log $k_N$ vs $pK_a$) are biphasic concave downwards with breakpoints at X = H. The Hammett plots for substituent Y variations in the substrates (log $k_N$ vs ${\sigma}_Y$) are biphasic concave upwards/downwards with breakpoints at Y = H. The cross-interaction constant $\rho_{XY}$ values are all negative: $\rho_{XY}$ = -0.32 for X = Y = electron-donating; -0.22 for X = electron-withdrawing and Y = electron-donating; -1.80 for X = electron-donating and Y = electronwithdrawing; -1.43 for X = Y = electron-withdrawing substituents. Deuterated kinetic isotope effects are primary normal ($k_H/k_D$ > 1) for Y = electron-donating, while secondary inverse ($k_H/k_D$ < 1) for Y = electronwithdrawing substituent. The proposed mechanisms of the benzylaminolyses of N-methyl-Y-${\alpha}$-bromoacetanilides are a concerted mechanism with a five membered ring TS involving hydrogen bonding between hydrogen (deuterium) atom in N-H(D) and oxygen atom in C = O for Y = electron-donating, while a concerted mechanism with an enolate-like TS in which the nucleophile attacks the ${\alpha}$-carbon for Y = electronwithdrawing substituents.