• Journal of Applied Biological Chemistry
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• v.56 no.1
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• pp.53-57
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• 2013

In here, we investigated the quantitative analysis method of indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) with liquid chromatography-mass/mass spectrometry (LC-MS/MS) or gas chromatography-MS. Two ways of clean-up process were investigated for LC-MS/MS instrumental analysis of IAA, but both a simple dilution and hydrophile-lipophile balance (HLB) solid phase extraction (SPE) were not met the optimal recovery rates for quantitative analysis. On the other hand, the clean-up method for GC-MS was finally optimized through HLB-SPE from 250-folds diluted sample and methylation with trimethylsilyl chloride in methanol for 4 h. The limit of detection for methyl ester of IAA and IBA were both 1.4 mg/L, and recovery rates showed 93-107% from the concentrated liquid fertilizer.

• Journal of the Korean Institute of Gas
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• v.19 no.3
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• pp.18-24
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• 2015

The flash point is one of the most important indicators of the flammabiliy of liquid solutions. The flash point is the lowest temperature at which there is enough concentration of flammable vapor to form an ignitable mixture with air. In this study the flash points of binary flammable solutions, 2-propanol+propionic acid and n-hexanol+formic acid systems, were measured using Seta flash closed cup tester. Particularly n-hexanol+formic acid system exhibited minimum flash point behavior. The measured values were compared with the calculated values using Raoult's law and optimization method. The calculated data by optimization method described the measured values more effectively than those calculated by Raoult's law.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.6
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• pp.744-751
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• 2007

Wet scrubber is widely used to remove toxic gaseous contaminants in various industries such as semi-conductor industry, display manufacturing industry and so on. In this study, to optimize a packed bed scrubber as one of typical wet scrubber size while keeping its performance, four different packing materials were investigated at different air flow rates, liquid-gas ratios and pH values. Ammonia, hydrochloric acid and hydrofluoric acid were used as test gases to characterize the scrubber performance. Gas removal efficiency increased as the packing size decreased, which resulted in the increase of specific surface area. The increase of air flow rate led to the decrease of gas removal efficiency, while the increase of liquid-gas ratio led to the increase of gas removal efficiency. For the case of $NH_3$ gas, lower pH, and for the cases of HCl and HF, higher pH contributed to higher gas removal efficiency. Gas removal efficiency of a wet scrubber increased in the order of HCl < $NH_3$ < HF according to its water solubility.

• KSBB Journal
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• v.15 no.4
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• pp.408-410
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• 2000

The supercritical fluid extraction(SFE) technique was applied for the isolation and purification of nonpolar physiologically acitve mateials from Agaricus blazei fruiting bodies. the qualitative analysis of extract was accomplished by gas chromatography-mass spectrometer(GC-MS) and extract was determined as linoleic acid(cis-9 cis-12-octadecadienoic acid) In order to obtain the optimum operating conditions of supercritical fluid extraction process the various temperatures and pressures were applied for process operation. From the comparison of exraction efficiencies $50^{\circ}C and 200 kg_f/cm^2$ were determined as optimum conditions.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.3
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• pp.74-80
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• 2005

The compositions of residual extractives in woodmeal, unbleached and oxygen-delignified aspen kraft pulps were investigated with gas chromatography(GC) and gas chromatography-mass spectrometry (GC-MS) with focus on fate of extractives in kraft pulping and oxygen delignification. Steryl esters and shorter retention time (shorter than palmitic acid) extractives were main extractives in aspen woodmeal. Shorter retention time extractives were well removed in kraft pulping. Sterol esters were hydrolyzed to sterols and fatty acids. Sterols and fatty acids were two major extractives classes in unbleached kraft pulps. Linoleic acid was main fatty acids in unbleached pulps compared with palmitic acid which is generally found in aspen woodmeal. Sterolsand fatty acids were also two major extractives classes in oxygen-delignified kraft pulps. However, linoleic acid was well removed in oxygen delignification.

• Korean Journal of Pharmacognosy
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• v.18 no.3
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• pp.184-187
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• 1987

Fatty acids and sterols were isolated from petroleum ether extract of seeds of Acanthopanax sessiliflorum Seeman. Fatty acids were obtained from the saponified fraction and sterols from nonsaponified fraction of petroleum ether extract. Fatty acids were identified by gas liquid chromatography, and its composition was myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid. The composition of sterols were determined by preparative TLC and gas liquid chromatography. It was confirmed to be a mixture of stigmasterol and ${\beta}-sitosterol$. These fatty acids and sterols were not previously reported from seeds of Acanthopanax sessiliflorum Seemann.

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.253-256
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• 2006

The purpose of this study was to develop a gas chromatographic (GC) method to analyze fatty acids in milk fat with a single injection. The single-injection GC method we developed for analyzing fatty acid composition can separate a wide range of fatty acid methyl esters from butyric acid to docosahexaenoic acid. It separated 6 isomers of 18:1 (cis-6, cis-9, cis-11, trans-6, trans-9 and trans-11), 4 isomers of 18:2 (cis-9-cis-12, trans-9-trans-12, cis-9-trans-12 and trans-9-cis-12), and 4 isomers of conjugated 18:2 (cis-9- trans-11, trans-9-cis-11, cis-10-trans-12 and trans-10-cis-12).

• Korean Journal of Clinical Laboratory Science
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• v.37 no.3
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• pp.164-167
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• 2005

Cellular fatty acid composition of 17 strains of the Pseudomonas aeruginosa was determined by gas-liquid chromatography isolated from environmental and clinical sample in a C university hospital. Straight-chain saturated acid of C16:0 and straight-chain unsaturated acid of C18:1 with a double bond were commonly found in all the strains tested. The presence of 12:0 3OH (3-10%), 16:0 (18-28%), and 18:1w7c (17-37%) showed the characteristics of the species in the Pseudomonas. Bacterial fatty acid composition was considered to be useful for the study of interrelation and for rapid identification of the bacteria.

• Korean Journal of Food Science and Technology
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• v.11 no.4
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• pp.278-282
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• 1979

Sugars and organic acids in Korean hot pepper fruit (C, annuum L.) according to its portions, pericarp, seeds and placenta, were determined by gas liquid chromatography (GLC). ${\alpha}-\;and\;{\beta}-fructoses,\;{\alpha}-\;and\;{\beta}-glucoses$, galactose, sucrose and maltose were identified. Major sugar in pericarp was fructose, while those in seeds and placenta were surose and fructose. Amount of free sugars in seeds was higher than that in pericarp or placenta. Succinic, fumaric, malic, tartaric, citric and quinic acids were found. Citric acid was a major organic acid found in pericarp and placenta. The amount of each identified organic acid, however, was similar in seeds. Quantity of total organic acids identified in pericarp or placenta was higher than that in seeds.

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.9-18
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• 1987

The effects of procedures for preparation of fatty acid methyl esters for gas chromatography were investigated. A quantitative comparison of four procedures for the preparation of the fatty acid methyl esters from Korean sesame seed lipids which can be representative of fatty acid ranges of Korean vegetable oils has been made. The procedures employed were $BF_3$-methanol, HCI-methanol, sodium methoxide-methanol, and tetramethylammonium hydroxide-methanol. Twelve fatty acids ranged from 14:0 to 24:0 were identified in the lipids from Korean white and black sesame seeds. All four procedures gave similar results for the fatty acids, 16:0, 18:0, 18:1, 18:2, and 18:3 present in the range of $1{\sim}44%$ but only in the HCI-methanol procedure, the fatty acids, 16:1, 20:0, 22:0, 24:0 present in the range of $0.02{\sim}1%$ showed the lowest values. When using tetramethylammonium hydroxide-methanol procedure for determination of total fatty acid composition from white and black sesame seed lipids, unsaponifiable matters including sesamol, sesamolin and sesamin present in the seed lipids are not removed from the resulting reaction mixture. Thus the transesterification mixture is used without further treatment for injection into the gas chromatography. However, the gas chromatographic analysis of the transesterification mixture showed that the unsaponifiable matters had no effect on the fatty acid composition of the seed lipids. From the results, it appears that the $BF_3$-methanol, sodium methoxide-methanol and tetramethylammonium hydroxide-methanol procedures can be used to prepare fatty acid methyl esters from Korean vegetable oils. Among the methods, the tetramethylammonium hydroxide-methanol procedure, which give total fatty acid composition, glyceride fatty acid composition and composition of free fatty acids present, appears to be a simple, convenient and quantitative procedure and applicable to samples containing broad ranges of fatty acids.