• YAKHAK HOEJI
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• v.44 no.5
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• pp.384-390
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• 2000

Metabolism study of the dye, benzidine, was performed by gas chromatography-mass selective detector (GC/MSD) in the urine of rats orally administered 100 mg/kg benzidine. Urine samples were collected in metabolic cages for 0-24, 24-48, and 48-72 hrs. Ten ml of the urine was extracted with XAD-2 resin and the XAD-2 column was eluted with methanol. After evaporation, benzidine and its metabolites were extracted with diethyl ether (for non-conjugated fraction). For conjugated metabolites, $\beta$-glucu-ronidase was added to the aqueous layer that was incubated for 1 hr at 5$0^{\circ}C$ and the aqueous layer was extracted as in non-conjugated fraction. Aliquot of trimethylsilylated derivatives was applied to the GC/MSD. The mutagenicity of benzidine and its acetylated metabolites was tested by histidine/reversion assay. Five metabolites observed and confirmed either by electron impact and chemical ionization modes of the GC/MSD, or authentic compounds were monoacetyl-, diacetyl-, hydroxyacetyl-, hydroxydiacetyl-, and hydroxy-benzidine. Monoacetyl-benzidine was more potent than benzidine in histidine/reversion assay. This data indicates that monoacetylation of benzidine may be one of the metabolites produced in metabolic activation process.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.8-17
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• 2002

In this study, it was tried to analyze not only total hydrocarbon but individual hydrocarbon components from C$_1$to C$\sub$6/ in exhaust gas using gas chromatography to seek the reason fur remarkable differences of smoke emission of diesel fuel, esterfied rice bran oil and blended fuel(esterfied rice bran oil 20vo1-% + diesel fuel 80vo1-%). Individual hydrocarbons(C$_1$ ∼C$\sub$6/) as well as total hydrocarbon of esterfied rice bran oil is reduced remarkably compared with diesel fuel. Although smoke emission of esterfied rice bran oil reduced remarkably compared with commercial diesel fuel, NOx emission of esterfied rice bran oil and blended fuel was increased slightly at high loads and speeds. And, it was tried to reduced NOx emission of them by exhaust gas recirculation(EGR) method. Simultaneous reduction of smoke and NOx emission was achieved with the combination of esterfied rice bran oil and EGR method in consequence.

• Applied Biological Chemistry
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• v.35 no.1
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• pp.36-41
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• 1992

Several commercial cottonseed, corn and rapeseed oils were stored at $60^{\circ}C\;and\;70^{\circ}C$ with daily exposure of fluorescent light for 12 hours and evaluated their rancidity by headspace gas chromatographic analysis of pentanal and hexanal. The data of gas chromatographic analysis was compared with organoleptic flavor evaluation. For headspace gas chromatographic analysis, the volatile compounds were recovered by porous polymer trap and flushed into a fused silica capillary column at $250^{\circ}C$. Twenty-three GC peaks were identified on the basis of relative retention time of reference compounds and gas chromatography-mass spectrometry. The results showed that the contents of pentanal and hexanal were linearly increased during storage. A very simple linear relationship was found between organoleptic flavor scores and amounts of two volatile compounds with very high correlation coefficient. This results suggested the possible implication of pentanal and hexanal as an quality index for rancidity evaluation of cottonseed, corn and rapeseed oils.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.11-12
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• 2003

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.314.1-314.1
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• 2003

Examination was made of the urinary metabolite(s) of CKD-712, which is a chiral compound, named S-YS49 derived from higenamine (one component of Aconite spp.) derivatives. First of all. to analyze the metabolite(s) of CKD-712, a simple and sensitive detection method for CKD-712 was developed by using gas chromatography-mass spectrometry(GC/MS). (omitted)

• 한국해양학회지
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• v.20 no.1
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• pp.74-82
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• 1985

Exposed on the sea, the oils are affected by the combined effects of evaporation, solution, chemical oxidation, and biological decomposition. Therefore the samples were taken after artificial weathering, and they were analyzed by gas chromatography for sulfur and hydrocarbons. The measurement results of gas chromatography have shown characteristic patterns. The peaks of the lower hydrocarbons in pollutant oil decreased with time. But the chromatograms for sulfur compound analysed by FPD showed little changes with lapse of time. The hydrocarbon and sulfur compound analysis by gas chromatography can be effectively used for analyzing oils for comparative identification.

• Korean Journal of Pharmacognosy
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• v.4 no.2
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• pp.71-74
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• 1973

The contents of volatile oil and camphor in the oil of Artemisia messer-schmidtiana $B_{ESSER}$ var. viridis $B_{ESSER}$ f. typica $N_{AKAI}$ and Artemisia asiatica $N_{AKAI}$ which were known to be effective as antibacterial, antifungal and antineoplastic agents by screening experimentation, were determined quantatively by gas chromatography. The volatile oil contents of Artemisia messer-schmidtiana $B_{ESSER}$ var. viridis $B_{ESSER}$ f. typica $N_{AKAI}$ and Artemisia asiatica $N_{AKAI}$ are 0.17% and 0.19%, and the camphor contents are 8.51% and 1.46%, respectively.

• Natural Product Sciences
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• v.16 no.3
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• pp.180-184
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• 2010

The simple and accurate method was established for the simultaneous determination of (-)-menthone and (-)-menthol in Menthae herba obtained from Korea and China. A quantitative analysis was performed with a gas chromatography-flame ionization detector and reference compounds were separated on a capillary HP-Innowax column (30 m $\times$ 0.23 mm, 0.50 ${\mu}m$, Agilent, MA, USA). The correlation coefficients of the compounds showed good linearity ($r^2$ > 0.9997) over the linear range. The precision, repeatability and stability showed less than 1.7% of relative standard deviation (RSD) values for two compounds. Recovery rates were within the range of 95.72 - 103.76%. The method was applied successfully to analyze 15 samples of Menthae herba and achieved sufficient and specific separation of reference compounds. The principal component analysis (PCA) exhibited the classification of 15 samples according to their locations of origin.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.379-383
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• 2009

For an accurate risk assessment of furan, a potential human carcinogen, levels must be determined in human blood plasma using a simple and robust assay. In this study, solid phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) was used to analyze blood plasma levels of furan in 100 healthy individuals who consumed a normal diet. The subjects were 30 to 70 years of age and 51% were women. Ultimately, an analytical method was established for analyzing furan in human blood. The limit of quantification (LOQ) and furan recovery rate in blood were 1.0 ppb and 104%, respectively. Finally, furan was detected in 21 individuals (13 males, 8 females) with levels ranging up to 17.86 ppb (ng furan/g food).

• YAKHAK HOEJI
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• v.19 no.4
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• pp.240-245
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• 1975

The quantitative analysis of ethambutol.2HCl as well as commercial ehambutol preparations was undertaken by gas-liquid chromatography by finding optimum conditions, such as the use of internal standard, stability of an ethambutol-2HCl-caffeine standard solution, and the effect of column temperature, N, O-bis-(trimethylsily) acetamide [B.S.A.] concentrations and other substances present in the preparations. Under the chromatiographic conditions, an ethambutol-2HCl. caffeine standard, 9 min, 30sec. The relative molar response of ethambutol.2HCl and caffeine studied was 2.08. Ethambutol.2HCl could be quantitated up to 1$\times$10$^{-8}$ moles. the possible decomposition of B.S.A. due to the moisture when tested and the incoplete reaction for silylation could be minimized.