• The Korean Journal of Food And Nutrition
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• v.11 no.4
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• pp.375-380
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• 1998

A study of characteristics of greenish pigments from silkwarm excrement by ethanol extraction. Through visible absorption scanning, it showed two absorption peaks at 415 and 657nm, and it was shown to be greenish color. In the presence of light, the stability of pigments rapidly degraded, but in the presence of Al-foil, green and blue cover were very stable. It was shown to be stabilized at the temperature of 7$0^{\circ}C$ until 20days and presence of metal ions, such as Na+, K+, Ca2+, Mg2+ and Zn2+. The pigments was shown to be stabilized in 5% acetic acid solution, but in the presence of lactic acid, citric acid and tartaric acid solution were unstable. On the result of TLC analysis, pigments were shown to be composed of eight color fractions, and main color fractions were F-1, F-2 and F-3. In F-1, F-2 fractions were revealed green color and F-3 fraction were revealed yellow color.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.3
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• pp.134-138
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• 2012

Recently the preparation magnetic nanoparticles by a pulsed laser ablation in liquid has gained much attention because it is easy to control experimental parameters. Iron oxide magnetic nanoparticles have been prepared by a pulsed laser ablation of ${\alpha}-Fe_2O_3$ target in ethanol at different magnitude of laser energy of 1, 20, 40 and 80 mJ/pulse. It revealed that particle size increases with increasing laser energy. It could be concluded that 40 mJ/pulse is an optimum laser energy for the preparation of iron oxide nanoparticles with uniform size distribution. The nanoparticles are homogeneously dispersed in ethanol and their stability maintained for several months.

• Macromolecular Research
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• v.15 no.5
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• pp.403-411
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• 2007

Monodisperse micron-sized polystyrene (PS) spheres were successfully obtained using a single stage soap-free emulsion method in aqueous media mixed with ethanol (co-solvent) containing NaCI as the electrolyte. The optimum conditions for preparing the monodisperse PS microspheres, using soap-free emulsion polymerization in a water/ethanol mixture with an electrolyte, were studied. The presence of the co-solvent and electrolyte controlled the particle dispersion stability during the polymerization. The microspheres formed using PS, with a weight-average diameter of $2.6{\mu}m$, coefficient of variation of 5.3% and zeta potential of -15.1 eV, were successfully obtained in the presence of 0.1 wt% NaCI, 10 wt% monomer, 0.1 wt% initiator and 95/5 (g/g) of a water/ethanol mixture reacted at $70^{\circ}C$ for 24 h.

• Food Science of Animal Resources
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• v.43 no.6
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• pp.961-974
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• 2023

This study investigated the effects of mustard seed extracts on physicochemical and storage characteristics of dry-aged pork loin ham during the aging period. In experiment 1, antioxidant activity was assessed for mustard seed extracted with varying ethanol concentrations and the results showed high antioxidant activity at 25%, 50%, and 75% ethanol concentrations. In experiment 2, pork loin was treated with mustard seed extracts obtained using different ethanol concentrations: not treated (control), 25% (MS25), 50% (MS50), and 75% (MS75). Physicochemical and storage characteristics of pork loin ham were measured in wk 0, 2, 4, and 6. The pH, a_w, CIE b^*, thiobarbituric acid reactive substances and volatile basic nitrogen values were lower in treated samples compared to the control (p<0.05). In conclusion, applying mustard seed extracts, particularly MS75, in the dry-aged pork loin ham production process could enhance storage stability and improve color attributes without having negative impacts on product quality.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.511-517
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• 2013

In this work, a fibrous bed bioreactor with high specific surface area and good adsorption efficacy for S. cerevisiae cells was used as the immobilization matrix in the production of ethanol. In batch fermentation, an optimal ethanol concentration of 91.36 g/l and productivity of 4.57 g $l^{-1}\;h^{-1}$ were obtained at an initial sugar concentration of 200 g/l. The ethanol productivity achieved by the immobilized cells was 41.93% higher than that obtained from free cells. Ethanol production in a 22-cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in packed-bed reactors, a maximum ethanol concentration of 108.14 g/l and a productivity of 14.71 g $l^{-1}\;h^{-1}$ were attained at $35^{\circ}C$, and a dilution rate of 0.136 $h^{-1}$ with 250 g/l glucose.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.4
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• pp.130-138
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• 2007

The aim of this study was to assess the cosmeceutical activies of four kinds of Korea herb medicine extracts using in cosmetics and related industries. The cosmeceutical activities of extracts were investigated by tyrosinase inhibition, astringent, anti-bacterial and MTT assay for cell viability. In the whitening effect, PA that the highest tyrosinase inhibition activity showed 56% at 10 ppm in ethanol extract. Also water and ethanol extract of RE showed 54%, 68% at 1,000 ppm, respectively, but LE and CA showed lower effect. Astringent effect of water and ethanol extract of PA appeared over 60% at 1,000ppm concentration but other extracts showed no astringent effect. In the anti-bacterial test, water and ethanol extract of PA showed no anti-bacterial effect against all microorganisms. But water and ethanol extract of RE showed anti-bacterial effect on Staphylococcus aureus, ethanol extract of showed on Staphylococcus aureus and Propionibacterium acnes, ethanol extract of CA showed on Candida albicans. The resUlt of stability test showed that the emulsion of containing PA were very stable at various temperature and sun-light test. Viscosity and pH of emulsion did not change. From the results of human patch test to assess the safety of cosmetics containing PA there was no negative reaction on skin was found.

• KSBB Journal
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• v.10 no.3
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• pp.231-236
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• 1995

For continuous ethanol production In an immobilized cell reactor consisting of Saccharomyces sake, feedings of one tenth to three tenths times diluted fermentation media were effective for maintaining the high ethanol productivity and physical stability of immobilized beads. In case two tenths times dilltued one of the fermentation medium supplemented with egg albumin hydrolysate(0.5%) and phosphatidylcholine(0.5%) was fed, a maximum ethanol productivity of $69 g/\ell$-hr was attained at a dilution rate of$1.1lhr^{-1}$, and it was 50% higher than that of the two tenths times diluted one of the fermentation medium without any supplement, $46 g/\ell$-hr.

• Journal of Biosystems Engineering
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• v.31 no.5 s.118
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• pp.443-448
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• 2006

For development of an on-line monitoring unit of fermentation process, an auto dilution unit based on traditional chemical and biological analytical method was developed and the performance was evaluated. The dilution unit was constructed with two syringe pumps and flow direction change valves and fully automated. Total delivery volume of two pumps using distilled water was measured to confirm the operating stability And diluted concentrations of three substrate solutions (glucose, lactic acid, ethanol) were compared with a standard method with a high performance liquid chromatograph (glucose, lactic acid) and gas chromatograph (ethanol). Relative error values of total delivery volume of the pumps were below 3% and standard deviation values were 0.003 (n=5). Relative error values of diluted concentration of the dilution unit measurements were below 2% with 1/10 of dilution ratio and 70, $80{\mu}{\ell}$ of sample volume conditions for glucose and lactic acid, 1/30 of dilution ratio and $70{\mu}{\ell}$ of sample volume conditions for ethanol, respectively. In case of the ethanol, cause of the evaporative characteristics, the relative error values showed over 5% whole experimental conditions.

• Journal of the Korean Electrochemical Society
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• v.11 no.3
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• pp.141-146
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• 2008

Electrocatalytic activities and stabilities of Pt supported on Sb-doped $SnO_2$ (ATO) were examined for ethanol oxidation reactions. Pt colloidal particles were deposited on ATO nanoparticles (Pt/ATO) and the prepared electrocatalysts were characterized by X-ray diffraction, transmission electron microscopy (TEM), and cyclic voltammetry. Electrochemical activity of the Pt/ATO for ethanol electro-oxidation was compared to those of Pt supported on carbon (Pt/C) and commercial PtRu/C. The activitiy of the Pt/ATO was much higher than those of the Pt/C and commercial PtRu/C. The Pt/ATO exhibited much higher electrochemical stabilities than the Pt/C in 0.5M ${H_2}{SO_4}$ and in 0.5M ${H_2}{SO_4}$/1M ${C_2}{H_5}OH$. According to TEM, the growth rate of Pt particles was lower in the Pt/ATO than it was in the Pt/C. The ATO nanoparticle appears to be a promising support material that promotes electrochemical reactions and stabilizes catalyst particles in direct ethanol fuel cell.

• Analytical Science and Technology
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• v.11 no.2
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• pp.145-149
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• 1998

Stability constants for the complexes of multidentate N,O-Schiff base ligands (bis-(salicylaldehyde)ethylendiamine(SED), bis-(salicylaldehyde)propylendiamine(SPD), bis-(salicylaldehyde)diethylenetriamine(SDT), bis-(salicylaldehyde)triethylenetetraamine(STT), and bis-(salicylaldehyde)tetraethylenepentaamine(STP) with Co(II) and Zn(II) were determined by a potentiometric method in a 70% dioxane-30% water mixture and ethanol, respectively. Stability constants for the complexes increased in the order of SPD