• Journal of Electrochemical Science and Technology
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• 제3권2호
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• pp.80-84
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• 2012

The polyaniline (PANI) electrodes are prepared by chemical synthesis and electrodeposition methods and their supercapacitive properties are characterized and compared by morphology observation, cyclic voltammetry as a function of scan rate, and impedance spectra analysis. In particular, the supercapacitive properties obtained in the range of higher potential scan rates (e.g., over $200mV\;s^{-1}$) are emphasized to be capable of utilizing adequately the high power capability of supercapacitor. As a result, the PANI electrode by the electrodeposition shows superior specific capacitance (max. $474F\;g^{-1}$ at $10mV\;s^{-1}$ and about $390F\;g^{-1}$ at $500mV\;s^{-1}$) than those by the chemical synthesis method. This is mainly due to highly porous structure obtained by the electrodeposition to yield higher specific surface area.

• 한국축산식품학회지
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• 제33권5호
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• pp.565-571
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• 2013

An enzyme ${\beta}$-galactosidase or ${\beta}$-galactohydrolase [EC3.2.1.23], commonly called lactase, mediates galacto-oligosaccharide (GOS) synthesis under conditions of high substrate concentrations. Also, lactase hydrolyzes ${\beta}$($1{\rightarrow}4$) lactose into glucose and galactose, the latter is successively transferred to free lactose to make various oligosaccharides via transgalactosylation. GOS is non-digestible to human digestive enzymes and has been used as a functional prebiotics. Among the 24 lactic acid bacteria (LAB) strains used, Lactobacillus paracasei YSM0308 was selected based on its exhibition of the highest ${\beta}$-galactoside hydrolysis activity, and the crude lactase was prepared for examination of reaction conditions to affect the GOS synthesis. Lactase activity was measured with a spectrophotometer using ONPG (o-nitropheyl ${\beta}$-D-galactopyranoside) method. Lactase activity was not detected in the culture supernatant and was mostly present in the cell pellet after centrifugation. Activity of the crude lactase preparation ranges from102 to 1,053 units/mL, with the highest activity determined for L. paracasei YSM0308. Optimal conditions for GOS synthesis are as follows: concentration of whey powder, pH, temperature, and time were 30%, pH 6.5-7.0, $30^{\circ}C$, and 4 h, respectively. The final GOS concentration was 19.41% (w/v) by the crude YSM0308 lactase, which was obtained from strain YSM0308 grown in the 10% (w/v) reconstituted whey-based medium.

• Bulletin of the Korean Chemical Society
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• 제27권6호
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• pp.847-852
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• 2006

Imidazolium tetrafluoroborate ionic liquids having unsaturated aliphatic side chains were synthesized and characterized. Most of them are liquid at room temperature and all of them are stable up to $300{^{\circ}C}$. Some imidazolium tetrafluoroborates with an allylic side chain showed much wider voltage windows on the platinum electrode, better conductivities, and lower viscosities compared with the corresponding ionic liquids containing the saturated side chains.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1537-1540
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• 2014

• Journal of Applied Biological Chemistry
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• 제44권2호
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• pp.84-86
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• 2001

Capsaicin synthesis by suspension cultured cells of Jalapeno pepper (Capcicum annuum L.) was assessed in vitro under various conditions including temperature (23 and $30^{\circ}C$), light intensity (with light and without light), and shaking speed (110 and 200 rpm). Capsaicin production increased, while the cell biomass growth decreased possibly due to the production of a secondary metabolite. Capsaicin synthesis was primarily affected by light condition. Cells cultivated at 110 rpm and $23^{\circ}C$ under light condition yielded the highest fresh weight, while those cultivated under the same condition, but without light resulted in the lowest cell mass. Capsaicin content in cells of 18-day-old pepper grown at 110 rpm and $23^{\circ}C$ under light was 0.125% of the cell mass. However, without light treatment, the capsaicin content in cells at the same shaking speed and temperature increased up to 169%, indicating no light is favored in the capsaicin synthesis by Jalapeno pepper. Increasing the shaking speed from 110 to 200 rpm without light enhanced the capsaicin synthesis. Results of this study demonstrate that light condition is the limiting factor in the synthesis of capsaicin in tissue-cultured Jalapeno pepper cells.

• Bulletin of the Korean Chemical Society
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• 제26권11호
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• pp.1889-1890
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• 2005

• Applied Biological Chemistry
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• 제1권
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• pp.43-47
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• 1960

1). By means of the F.H. Allene and James Allenes method of the ${\alpha}-methylindole$ synthesis, 2-methylindole was prepared with the Acetyl-o-toluidine and $NaNH_2$. yield; 88%, mp. $56.5{\sim}57^{\circ}C$. 2). 23.7 gr of 3-(-Nitro-1-phenylethyl)-2-melthylindole was prepared with 0.1 mol. of the 2-methylindole and 0.1 mol. of the ${\beta}-Nitrostyrene$. yield: 84.6%, mp. $104{\sim}105^{\circ}C$. 3). Analytical results. Calcd. for $C_{17}H_{16}N_2O_2$: C, 72.84; H, 5.63; N, 9.99. Found: C, 72.62; H, 5.63; N, 9.79.

• Journal of Applied Biological Chemistry
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• 제44권1호
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• pp.20-22
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• 2001

We have attempted to synthesize polyhydroxy stilbene compounds through the benzyl thioether moiety. During synthesis, we unexpectedly observed that demethylation of the compound under $AlCl_3$ in ethanethiol resulted in a regioselective addition of thiol to the double bond as well as complete demethylation. We report on the regioselective short synthesis for general structure and its structural identification.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.648-651
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• 2005

Synthesis and biological evaluation of a series of $C_4$-modified acanthoic acid analogs are reported. Among them, the analog 7 and 10 exhibit potent cellular inhibitory activity in NO inhibition assay.

• 대한화학회지
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• 제56권5호
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• pp.661-664
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• 2012