• Environmental Analysis Health and Toxicology
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• v.15 no.1_2
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• pp.45-51
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• 2000

Analytical method of 4-nitrotoluene (4-NT) in water was developed by 9as chromatography/mass selective detector/selected ion monitoring (GC/MSD/SIM). 4-NT was extracted with diethyl ether. Organic layer was washed with 5 % sodium chloride solution. The influence of solvent and evaporation condition on extraction of 4-NT were examined. The retention time of 4-NT peak was 7.72 min. Coefficient of variation (CV) of 4-NT (ng) within day and day-to-day was ranged from 7.0 to 14.6% and from 7.7 to 20.8%, respectively. Recovery of 4-NT was ranged from 84 to 109%, and detection limit of 4-H was lese than 1 ng/㎖.

• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.66-70
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• 2000

The volatile components of Korea ginger were compared by using different isolation methods, head-space sampling procedure(HSSP), simultaneous distillation extrction(SDE) and soild pahse micro-extractions(SPME). Sixty-one components were identified by GC-MSD in the extracts obtained from each extraction methods. However, the components identified showed a difference in their composition wit the extraction methods. In the extract by HSSP, fifty-five components including a high volatile compound such as acetaldehyde, ethylacetate, 2,3-butandione were detected, and thirty-one components were identified in the extract by SPME. While, the low volatile components such as elemol, zingiberenol and ${\beta}$-eudesmol were detected only in the extract by SDE method. The results suggest that SDE method is the best for the analysis of low volatile components, whereas HSSP is a proper method for the analysis of high volatile components from natural resources.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.4
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• pp.574-584
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• 1998

Antimicrobial activities, extraction yields and chemical compositions of the extract from the powder of vacuum dried Smilax china root on various solvents were investigated. Antimicrobial activities against. A rhizogenes, A. tumefaciens, C. utilis, S. cerevisiae, B. megaterium, B. subtilis and E. coli were measured by disc diffusion method. Methanol, chloroform, ethylacetate and butanol extracts exhibited potent antimicrobial activities against B. megaterium and B. subtilis. Also, methanol, ethylacetate and butanol extracts had the activities against A. rhizogenes, and chloroform and ethylacetate extracts against A. tumefacciens. The extraction yields were 13.10%, 8.71%, 2.73%, 0.83%, 0.54% and chemical compositions of their extracts were very different according to the kinds of solvents. The main chemical groups of ethylacetate, methanol, chloroform and butanol extracts were 45.99% phenolics, 36.10% acids, 29.13% phenolics and 18.96% phenolics, respectively.

• Journal of Environmental Science International
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• v.14 no.1
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• pp.81-89
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• 2005

As a typical example of simultaneous analysis of the odorous compounds, the volatile organic compounds from inventory sources in Seongseo industrial area were concentrated and analyzed with thermal desorber/GC/MSD, and major malodorous compounds were estimated. Odor intensity and odor concentration was analyzed simultaneously During a period from November in 2002 to December in 2003, this study was conducted to evaluate malodor emission characterization in major treatment facilities. The major components were Dimethyl sulfide, Dimethyl disulfide, Methyl mercaptane, Ammonia, Benzene, Toluene, m,p-xylene, o-xylene, Styrene, 1,2,4­T.M.B and 1,3,5-T.M.B. Among the six major inventory sources, the odor unit concentration of Night-soil disposal facilities was the highest, $669\~2344\;ou/m^{3}.$

• Korean Journal of Pharmacognosy
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• v.31 no.4
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• pp.455-458
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• 2000

Research on pesticide residues as endocrine disruptors in natural medicines was initiated by Korea Food & Drug Administration this year. We determined the presence and levels of certain pesticides in selected natural medicines. The natural medicines collected this year are Glycyrrhiza Root, Cinnamon Bark, Pueraria Root, Polygonatum Rhizome, Jujube, Schizandra Fruit, Lycium Fruit, Liriope Tuber, Eucommia Bark, Peony Root, Korean Angelica, Dioscorea Rhizome, Cnidium Rhizome, Cassia Seed, Platycodon Root, Comus Fruit, Mentha Herb, Epimedium Herb, Bupleurum Root, and Ginger, which have no data for pesticide residues and 192 samples of them were circulated in Korea, 28 samples were circulated in China. In order to analyze many pesticides in large number of samples we used simultaneous multi-residue analysis of pesticides by GC-ECD, which was followed by GC-MSD analysis to confirm the identity of the detected pesticide in each sample.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.2
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• pp.158-164
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• 2006

Offensive odor from CAFO(concentrated animal feeding operation) and its control have become a significant issue in Korea. Control of odors from the CAFO requires to identify major odorant and their generation mechanisms. In this study, an easy method to collect gas sample and to quantify its odorants is proposed. The method involves on-site odorant extraction with solid-phase microextraction and quantitation with GC/MSD or GC/FID. Analytes of the current study include: trimethylamine(TMA), carbon disulfide($CS_2$), dimethyl sulfide(DMS), dimethyl disulfide(DMDS), acetic acid(AA), propionic acid(PA) and n-butyric acid(BA). The resulting linearity($R^2$) of calibration curve for each analyte was good over the range from several ppbv to ppmv; 0.984 for TMA(0.056-1.437), 0.996 for $CS_2$(0.039-0.999), 0.994 for DMS(0.029-0.756), 0.995 for DMDS(0.024-0.623), 0.992 for AA(0.068-1.314), 0.955 for PA(0.047-0.940), and 0.976 for BA(0.036-0.712). Method detection limits were 5.67, 6.39, 5.78, 25.2, 0.098, 0.363 and 0.099 ppbv for AA, PA, BA, TMA, DMS, $CS_2$, and DMDS, respectively. With the developed method, odorants from poultry, swine, and cattle barns were analysed. All the compounds but DMDS were detected from the sample collected in the poultry barn, and their levels exceeded the representative published human olfactory threshold.

• Journal of the Korean Society of Tobacco Science
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• v.30 no.2
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• pp.94-102
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• 2008

In this paper, we describe our study on the characterization of tobacco leaves by their pyrolysis patterns. Two kinds of tobacco leaves were pyrolyzed and analyzed by Double-Shot Pyrolysis-Gas Chromatography/Mass Spectroscopy (Py-GC/MS) methods. Three grades of Korean flue-cured tobacco leafsuch as B1O, AB3O, CD3L and burley tobacco leaves such as B1T, AB3T, CD3W were pyrolyzed with six discrete but stepwise heating temperature ranges, those are from 100$^{\circ}C$ to 150$^{\circ}C$, 150$^{\circ}C$ to 200$^{\circ}C$, 200$^{\circ}C$ to 250$^{\circ}C$, 250$^{\circ}C$ to 300$^{\circ}C$, 300$^{\circ}C$ to 350$^{\circ}C$ and finally from 350$^{\circ}C$ to 400$^{\circ}C$. Using the resultant 52 pyrolytic components identified in the programs as components, principal component analysis (PCA) showed statistical classification between flue-cured and burley tobacco lamina. Among six pyrolysis temperature ranges, the best discrimination was achieved at the temperature range from 250$^{\circ}C$ to 300$^{\circ}C$ and from 300$^{\circ}C$ to 350$^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.61-65
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• 2001

To investigate the optimum condition of 3-monochloro-1, 2-propanediol(MCPD) analysis, gas chromatography with electron capture detector was used. Determination of MCPD derivatized with phenylboric acid was more effective than that of underivatized MCPD. In derivatization of MCPD with phenyl boric acid, there were no significantly different between boiling for 2min at 9$0^{\circ}C$ and vortexing for 5min at room temperature. Extrelut column was suitable for extraction of MCPD diluted in 20% NaCl solution and recovery rates were higher than direct extraction of MCPD with ethyl acetate. But, the method of direct extraction of MCPD with ethyl acetate was useful for rapid ants qualitative analysis. The sample extracted in soysauce(ganjang) was derivatized with phenylboric acid and analyzed by gas chromatography-mass selective detector. That was confirmed as MCPD-phenylboronate.

• Korean Journal of Food Science and Technology
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• v.34 no.3
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• pp.385-389
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• 2002

Analytical method for diethylstibestrol (DES) and zeranol, which are growth promoters, in muscle foods was studied. Through selected ion monitoring analysis by GC-MSD for hormones, $M^+$ 412, 420, 416, and 433 for DES, $D_8DES$, ${\beta}-estradiol$, and zeranol, respectively, were selected for quantitative analysis. Removal of interferences in meat was done by passing the meat through 1 cc of strong anion exchanges resin, Dowex $2{\times}8$, 400 mesh, whereby the recoveries of DES and zeranol were achieved. Recoveries of DES and zeranol were ranged from 85 to 110%, and 75 to 110%, respectively, in meat using $D_8DES$ as an internal standard, while were 82 to 105%, and 65 to 120%, respectively, using ${\beta}-estradiol$ as an internal standard. These results show that both $D_8DES$ and ${\beta}-estradiol$ can be adopted as the internal standard for the analysis of DES and zeranol in muscle foods. Limits of detection of DES and zeranol were 0.05 and 1.0 ng/g, and limits of quantitation were 0.5 and 1.0 ng/g, respectively. The results of this study revealed no DES and zeranol were present in 14 samples of beefs, porks, ducks, chickens, mutiplicated flat fish, and trout.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1412-1419
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• 2006

Concentrations of formaldehyde and acetaldehy de were respectively analysed in forty-five alcoholic beverages obtained from the market. After derivatization with PFBHA, GC-ECD and GC-MSD were employed for analysis. The peak area of aldehyde oximes (derivatives with PFBHA) increased with the increasing ethanol content (5%, 10%, 15%, 20% and 40%). When three-point calibration corves for the selected ethanol concentration (5, 13, 21 and 40%, v/v) were studied, suitable linearity against ethanol concentration was observed only under 5, 13, and 21% (ethanol, v/v). After analysis, maximum content of formaldehyde (average of 0.272 ppm) and acetaldehyde (average of 15.262 ppm) among the observed 45 alcoholic beverages was found from whisk (2 species) while minimum content of formaldehyde (average of 0.009 ppm) and acetaldehyde (average of 0.805 ppm) was found from diluted soju (4 species).