• Journal of the Korean Chemical Society
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• v.49 no.2
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• pp.129-137
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• 2005

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.43-49
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• 1996

Modulation of the catabolic PEP-pathway of Anaerobiospirillum succiniciproducens was tried using some enzymatic inhibitors such as gases and chemicals in order to enhance succinic acid production. 10$\%$ CO increased the succinic acid/acetic acid (S/A) ratio but inhibited growth as well as production of succinic and acetic acid. Hydrogen gas also increased the S/A ratio and inhibited the synthesis of pyruvate: ferredoxin oxidoreductase when used in mixture with $CO_2$, Catabolic repression by acetic, lactic and formic acid was not recognized and other modulators such as glyoxylate, pyruvate derivatives, arsenic salt, phosphate and sulfate were shown not to be effective. Magesium carbonate was shown effective for repressing acetate production. Palmitic acid, myristic acid and phenylalanine did not affect acetate production but carprylic acid completely inhibited growth.

• Korean Journal of Pharmacognosy
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• v.21 no.3
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• pp.235-238
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• 1990

Fatty acids, sterols and amino acids were confirmed from seeds of Acanthopanax senticosus for. inermis Harms. Fatty acids were isolated from petroleum ether extract and identified by gas liquid chromatography. Its composition was myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid and behenic acid. The composition of sterols that isolated from n-hexane extract were determined by GC/MS. It was confirmed to be a mixture of ${\beta}-sitosterol$ and stigmasterol. And several kinds of amino acids-cysteic acid, threonine, serine, proline, glutamic acid, glycine, alanine, valine, isoleucine, leucine, histidine, lysine and arginine-were confirmed from water fraction.

• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.67-72
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• 2013

The flash point is the lowest temperature at which there is enough concentration of flammable vapor to form an ignitable mixture with air. The flash point is a major physical property used to analyse the fire and explosion hazards of a flammable liquid solution. The flash point data for pure components are easily available in several literature. But the flash points of the flammable binary solutions appear to be scarce in the literature. The objective of this study is to measure and estimate the flash point of acetic acid-formic acid system. Cleveland open cup tester was used to measure the flash point. The experimental data were compared with the values estimated by the Raoult's law and the optimization methods based on van Laar and Wilson equations. As a result, the estmated values by optimization methods were found to be better than those based on the Raoult's law.

• Journal of Ginseng Research
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• v.42 no.1
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• pp.57-67
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• 2018

Background: Ginseng contains many small metabolites such as amino acids, fatty acids, carbohydrates, and ginsenosides. However, little is known about the relationships between microorganisms and metabolites during the entire ginseng fermentation process. We investigated metabolic changes during ginseng fermentation according to the inoculation of food-compatible microorganisms. Methods: Gas chromatography mass spectrometry (GC-MS) datasets coupled with the multivariate statistical method for the purpose of latent-information extraction and sample classification were used for the evaluation of ginseng fermentation. Four different starter cultures (Saccharomyces bayanus, Bacillus subtilis, Lactobacillus plantarum, and Leuconostoc mesenteroide) were used for the ginseng extract fermentation. Results: The principal component analysis score plot and heat map showed a clear separation between ginseng extracts fermented with S. bayanus and other strains. The highest levels of fructose, maltose, and galactose in the ginseng extracts were found in ginseng extracts fermented with B. subtilis. The levels of succinic acid and malic acid in the ginseng extract fermented with S. bayanus as well as the levels of lactic acid, malonic acid, and hydroxypruvic acid in the ginseng extract fermented with lactic acid bacteria (L. plantarum and L. mesenteroide) were the highest. In the results of taste features analysis using an electronic tongue, the ginseng extracts fermented with lactic acid bacteria were significantly distinguished from other groups by a high index of sour taste probably due to high lactic acid contents. Conclusion: These results suggest that a metabolomics approach based on GC-MS can be a useful tool to understand ginseng fermentation and evaluate the fermentative characteristics of starter cultures.

• Applied Biological Chemistry
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• v.12
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• pp.43-51
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• 1969

The purpose of this study was to determine protein amino acid contents of some Korean foods by gas-liquid chromatography, and to evaluate this technique as a procedure for the quantitative determination of amino acids in foods. The crude protein content of foods was also estimated from the nitrogen content. 1. Nitrogen content of each food sample was determined previously to adjust the amount of sample for GLC analysis 2. In the analysis of 17 known amino acids, a linear relationship was found between the weight of 13 amino acids of 17 amino acids, the internal standard as well as the injection volume of a mixture and the detector responses for the derivatives of the amino acids. No response for arginine, cystein, histidine, and tyrosine was observed. 3. The relative molar response (RMR) values for the 13 amino acids of standard solution relative to glutamic acid as '1.00' were obtained under normal operating conditions with a hydrogen flame ionization detector. 4. The recovery of amino acids from their mixtures with natural food materials was carried out. The recoveries were essentially quantitative except threonine and serine. An overall mean recovery of 11 amino acids was $101.4{\pm}8.4$ per cent before hydrolysis and $98.1{\pm}8.7$ per cent after hydrolysis of samples. 5. The comparative analysis of the acid hydrolysates of two food samples by gas-liquid and ion-exchange chromatographic analysis were carried out. In white-bait pemmican, only threonine and asparagine amounts by GLC analysis had similar values to those obtained by ion-exchange chromatography. The other seven amino acids gave higher values as measured by GLC than by ion-exchange. With the food sample, soybean, alanine, valine, asparagine, and glutamic acid were in good agreement in two analysis, while leucine, proline, threonine, phenylalanine, and lysine were found in slightly higher concentrations in the GLC analysis. 6. Grant variations of amino acid content were found among samples analyzed. The amino acid contents of each sample were compared with the values found in the literature.

• Korean Journal of Medicinal Crop Science
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• v.9 no.4
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• pp.275-279
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• 2001

The contents of chemical components such as total nitrogen, total amino acid, chlorophyll, vitamin C and free sugar were somewhat higher in $CO_2$ and $N_2$ gas treatment than those of other treatment. However, the contents of tannin and caffeine did not show any different in the 5 treatments. ${\gamma}-aminobutyric$ acid(GABA) and alanine accumulated in tea leaves under anaerovic condition. The content of GABA acid with ${CO_2\;and\;N_2}$ gas treatment was higher 8-6 times with values of ${264{\sim}215mg/100g}$ than in control (35mg/100g). The scores of sensory test was not different between anaerobic treatment and control. Consequently, tea mading within ${N_2\;and\;CO_2}$ gas treatment after plucking was considered to be the best green tea in terms of functional nature as well as taste nature.

• Journal of Microbiology and Biotechnology
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• v.28 no.3
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• pp.473-481
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• 2018

Owing to its high protein secretion capacity, simple nutritional requirements, and GRAS (generally regarded as safe) status, Bacillus licheniformis is widely used as a host for the industrial production of enzymes, antibiotics, and peptides. However, as compared with its close relative Bacillus subtilis, little is known about the physiology and stress responses of B. licheniformis. To explore its temperature-stress metabolome, B. licheniformis strains ATCC 14580 and B186, with respective optimal growth temperatures of $42^{\circ}C$ and $50^{\circ}C$, were cultured at $42^{\circ}C$, $50^{\circ}C$, and $60^{\circ}C$ and their corresponding metabolic profiles were determined by gas chromatography/mass spectrometry and multivariate statistical analyses. It was found that with increased growth temperatures, the two B. licheniformis strains displayed elevated cellular levels of proline, glutamate, lysine, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, and octadecanoic acid, and decreased levels of glutamine and octadecenoic acid. Regulation of amino acid and fatty acid metabolism is likely to be associated with the evolution of protective biochemical mechanisms of B. licheniformis. Our results will help to optimize the industrial use of B. licheniformis and other important Bacillus species.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.121-128
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• 2006

The interaction between adherent molecules and gas molecules was modeled in the molecular scale and simulated by the molecular dynamics method in order to understand evaporation and removal processes of adherent molecules on metallic surface using high temperature gas flow. Methanol molecules were chosen as adherent molecules to investigate effects of adhesion quantity and gas molecular collisions because the industrial oil has too complex structures of fatty acid. Effects of adherent quantity, gas temperature, surface temperature and adhesion strength for the evaporation rate of adherent molecules and the molecular removal mechanism were investigated and discussed in the present study. Evaporation and removal rates of adherent molecules from metallic surface calculated by the molecular dynamics method showed the similar dependence on the surface temperature shown in the experimental results.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2224-2226
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• 1999

Non-thermal plasma techniques is applied in many fields. Recently acid rain, global warming, ozone depletion, and smog are preeminent environmental problems. The cause for this environmental problems is the flue gas. Non-thermal plasma techniques has an attention for the solution of flue gas. Non-thermal plasma is used for the removal of flue gas composed of NOx, etc. This field has grown dramatically. This experiment is performed by using cylinder type reactor under the condition of room temperature and atmosphere pressure. NO gas is used instead of flue gas. Bidirectional pulse generator is used instead of the unidirectional pulse generator to increase the efficiency.