• 한국약용작물학회지
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• 제20권4호
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• pp.222-230
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• 2012

We evaluated the inhibitory effects of extracts and components of Geranium thunbergii on aldose reductase (AR) and galactitol formation in rat lenses with high levels of galactose as a part of our ongoing search of natural sources for therapeutic and preventive agents for diabetic complications. The inhibitory effects of water, methanol and ethanol extracts of G. thunbergii on rat lens AR (RLAR) were determined. Comparing inhibitory effects of various solvent extracts, ethanol extract showed RLAR inhibitory activity ($IC_{50}$ values, 5.24 and $6.39{\mu}g/m{\ell}$, respectively). The ethanol extract was fractionated to chloroform, ethyl acetate and water. Of these, the ethyl acetate fraction from ethanol extract of G. thunbergii exhibited RLAR inhibitory activity ($IC_{50}$ value, $2.64{\mu}g/m{\ell}$). In order to identify the bioactive components of ethyl acetate soluble fraction of ethanol extract from G. thunbergii, eight compounds, namely gallic acid (1), protocatechuic acid (2), p-hydroxybenzoic acid (3), brevifolin carboxylic acid (4), geraniin (5), ellagic acid (6), kaempferol-3-O-arabinofuranosyl-7-O-rhamnopyranoside (7), kaempferitrin (8) were isolated. The isolates were subjected to in vitro bioassays to evaluate their inhibitory activity on RLAR and galactitol formation in rat lenses. The ellagic tannins (5, 6) and flavonoid (7) exhibited strong inhibitory effects on RLAR. Also, these three compounds (5, 6 and 7) suppressed galactitol accumulation in rat lens under high galactose conditions, demonstrating the potential to prevent galactitol accumulation exo vivo. These results suggest that the extracts and components of G. thunbergii are a promising agent in the prevention or treatment of diabetic complications.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권6호
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• pp.587-592
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• 2005

Hydrolyzates from lignocellulosic biomass contain a mixture of simple sugars; the predominant ones being glucose, cellobiose and xylose. The fermentation of such mixtures to ethanol or other chemicals requires an understanding of how each of these substrates is utilized. Candida lusitaniae can efficiently produce ethanol from both glucose and cellobiose and is an attractive organism for ethanol production. Experiments were performed to obtain kinetic data for ethanol production from glucose, cellobiose and xylose. Various combinations were tested in order to determine kinetic behavior with multiple carbon sources. Glucose was shown to repress the utilization of cellobiose and xylose. However, cellobiose and xylose were simultaneously utilized after glucose depletion. Maximum volumetric ethanol production rates were 0.56, 0.33, and 0.003 g/L h from glucose, cellobiose and xylose, respectively. A kinetic model based on cAMP mediated catabolite repression was developed. This model adequately described the growth and ethanol production from a mixture of sugars in a batch culture.

• 한국수정란이식학회지
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• 제16권1호
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• pp.1-5
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• 2001

A total of 92 unfertilized human oocytes were treated with ethanol (EtOH), calcium ionophore A23187 (CI) or electric pulse (EP) for activating pronuclear formation and subsequent development. In Experiment 1, there was a significant (P=0.0001) treatment effect on the activation of unfertilized oocytes. No spontaneous activation was occurred in the control, but activation treatments induced PN formation with various efficacy. More unfertilized oocytes (UFOs) were activated after EtOH or EP treatment than after CI treatment. EP was as effective (63.6 %) as EtOH, but fragmentation was observed in 43% of UFOs activated by EP. Proportion of UFOs that formed presumptive haploid PN (2 PNs+1 PB or 1 PN +2 PBs) was 33.3, 0 and 28.6% after EtOH, CI and EP treatments, respectively. In Experiment 2, a significant (P=0.0362) effect of immature oocytes (IOs) status on activation was fecund. IOs at the GVBD-MI oocytes had higher potential to form PN than those at the GV stage or with abnormal morphology (25 vs. 77.8%). The results of this study clearly demonstrated that the treatment of 10% ethanol for 5 min effectively induced the activation of UFOs. IOs could form pronucleus with high efficacy by ethanol treatment, as long as they grew beyond the GVBD stage.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1459-1460
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• 2011

• KSBB Journal
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• 제4권2호
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• pp.69-73
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• 1989

Xylosw의 초기 농도가 2%, 4%, 8% 그리고 10%의 경우에 대하여 회분식 발효 실험을 하였다. 최대 ethanol수율은 2%, 4%, 8%과 10%의 xylose의 농도에 대하여 각각 0.46, 0.45, 0.43 그리고 0.42로 나타났다. Xylitol은 넓은 범위의 specific oxygen supply rate와 xylose 농도에서 거의 생성되지 않았다. 최대 specific productivity는 2-10%의 농도에 대하여 0.11, 0.11, 0.241, 0.0961g ethanol/hr-g DCW의 값을 보여주었다.

• Biomolecules & Therapeutics
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• 제6권4호
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• pp.345-350
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• 1998

The adverse effects of ethanol on cell proliferation have been described for a variety of tissues and cells. In the present study, we investigated whether chronic ethanol intoxication impairs the cell proliferation and DNA synthesis induced by oncogenic $H-ras^{V12}$ - and $v-K-ras^{V12}$-transformed cells. Ethanol treatment inhibited the cell proliferation and the DNA synthesis of control parental fibroblasts in a time- and dose-dependent manner. In contrast, ethanol did not suppress the proliferation of either oncogenic $H-ras^{V12}$ - or $v-K-ras^{V12}$ -transformed fibroblasts. Microinjection of oncogenic $H-Ras^{V12}$ protein induces DNA synthesis and ethanol treatment did not interfere with the DNA synthesis. The antiproliferative toxicity of ethanol was rescued by antioxidants, such as N-acetylcysteine and 4-methlpyrazole. These results indicate that the antiproliferative action site of ethanol toxicity lies upstream or is independent of Ras and ethanol exerts its toxicity through a free radical formation.

• 대한화학회지
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• 제38권4호
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• pp.271-275
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• 1994

아르곤과 일산화탄소가 포화된 에탄올 수용액의 광화학 반응을 184.9 nm의 자외선을 이용 연구하였다. 아르곤이 포화된 $1{\times}10^{-2}$M의 에탄올 수용액에서는 acetaldehyde와 2,3-butanediol만이 얻어졌으나, 일산화탄소가 포화된 용액의 광반응에서는 이들 두 가지 생성물 이외에 carboxylation 및 carboxylation반응이 진행되어 ${\alpha}$-hydroxypropionaldehyde, formaldehyde, glyoxal, formic acid, oxalic acid and glyoxylic acid등이 생성되었다. 그러나 에탄올의 농도가 증가한 용액의 광반응에서는 일산화탄소의 존재유무에 관계없이 carboxylation과 carboxylation반응은 관찰되지 않았다. 반응의 결과 얻어진 각 생성물들에 대한 initial quantum yield의 값들을 결정하였으며, 산소가 제거된 에탄올 수용액의 광반응에서 얻은 결과와 비교하여 가능한 반응메카니즘을 제시하였다.

• 한국미생물·생명공학회지
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• 제45권2호
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• pp.162-167
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• 2017

본 연구에서는 동시당화발효공정으로 바이오에탄올을 생산하기 위하여 바이오캡슐 형성을 시도하였다. 다수의 당화곰팡이 균주들과 발효 효모 균주들이 먼저 탐색되었다. Aspergillus sp. BCNU 6200, Penicillium sp. BCNU 6201 및 P. chrysogenum KACC 44363이 ${\alpha}$-amylase와 glucoamylase와 같은 당화 효소를 우수하게 생산하는 균주이었으며, Saccharomyces cerevisiae IFO-M-07이 조사된 균주 중에서 가장 에탄올 생산능이 높았다. 다음으로 pellet 형성 및 바이오 캡슐 형성을 위한 최적 조건을 평가하였다. 모든 조사된 곰팡이 모두 pellet을 형성하였으며, 바이오캡슐의 최적조건은 $28^{\circ}C$, 120 rpm이었다. 최종적으로 형성된 바이오캡슐을 이용하여 동시당화발효를 수행하여, Aspergillus sp. BCNU 6200의 바이오캡슐(Aspergillus sp. BCNU 6200 + S. cerevisiae IFO-M-07)이 10일간 발효시 $30^{\circ}C$, 120 rpm에서 3.9%의 에탄올을 생산함을 확인하였다. 본 실험 결과는 동시 당화발효 공정으로 바이오에탄올을 생산하는데 있어서 바이오캡슐을 활용함에 관한 유용한 정보를 제공하고 있다.

• The Plant Pathology Journal
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• 제18권2호
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• pp.77-80
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• 2002

A simple method for sporangial formation of the rice downy mildew pathogen, Sclerophthora macrospora, on infected leaf tissues was developed to facilitate diagnosis of the disease. Freshly infected young leaves showing whitish to yellowish small spots were selected and cut into small pieces about 2-3 cm in length. About 10-20 pieces were surface sterilized in a 100 ml Duran bottle with 40 ml of 70% ethanol by vigorous shaking for 30 seconds. After washing three times with distilled water, the leaf cuts were submerged in 10 ml of Millipore-filtered paddy water and incubated at $20^{\circ}C$ in the dark. After 8-10 h of incubation, the bottle was vigorously agitated on a vortex mixer, Aliquot amount of the suspension, 0.1-1.0 m1, was spread on a slide glass and examined under a light microscope at 50 or 100x magnification. It was found that light and 1% NaClO strongly inhibit sporangial formation of S. macrospora. Meanwhile, the use of freshly infected young loaves and washing with 70% ethanol stimulated sporangial formation of the fungus on rice leaves.

• Macromolecular Research
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• 제12권4호
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• pp.399-406
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• 2004

Glass-like carbon precursors shrink significantly during curing and carbonization, which leads to crack formation and bending. Cured furan resin powder and ethanol were added to furan resin to diminish the weight loss, to suppress the shrinkage and bending, and to readily release the gases evolved during polymerization and curing. Curing and carbonization were controlled by pressure and slow heating to avoid damage to the samples. The effect of the filler and ethanol on the fabrication process was examined by measuring the properties of the glass-like carbon, such as the specific gravity, bending strength, electrical resistivity, and microstructural change. The specific gravities of the filler-added glass-like carbons were higher than those of the ethanol-added samples because of the formation of macropores from the vaporization of ethanol during the curing and polymerization processes. Although the ethanol-added glass-like carbons exhibited lower bending strengths after carbonization than did the filler-added samples, the opposite result was observed after aging at 2,600$^{\circ}C$. We found that the macropores created from ethanol were contracted and removed upon heat treatment. The electrical resistivity of the glass-like carbon aged at 2,600$^{\circ}C$ was lower than those of the samples carbonized at 1,000$^{\circ}C$. We attribute this phenomenon to the fact that aging at high temperature led to well-developed microstructures, the removal of macropores, and the reduction of the surface area.