• Food Science and Biotechnology
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• 제18권3호
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• pp.700-705
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• 2009

In this study, the volatile compounds in 9 commercial fermented soybean pastes were extracted and analyzed by headspace-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS), respectively. A total of 63 volatile components, including 21 esters, 7 alcohols, 7 acids, 8 pyrazines, 5 volatile phenols, 3 ketones, 6 aldehydes, and 6 miscellaneous compounds, were identified. Esters, acids, and pyrazines were the largest groups among the quantified volatiles. About 50% of the total quantified volatile material was contributed by 5 compounds in 9 soybean paste samples; ethyl hexadecanoate, acetic acid, butanoic acid, 2/3-methyl butanoic acid, and tetramethyl-pyrazine. Three samples (CJW, SIN, and HAE) made by Aspergillus oryzae inoculation showed similar volatile patterns as shown in principal component analyses to GC-MS data sets, which showed higher levels in ethyl esters and 2-methoxy-4-vinylphenol. Traditional fermented soybean pastes showed overall higher levels in pyrazines and acids contents.

• 한국식품조리과학회지
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• 제30권5호
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• pp.596-602
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• 2014

Dutch coffee is extracted in low temperature for a longer time than espresso and drip coffee. This study was conducted to investigate changes in the flavor compounds in Dutch coffee resulting from different extraction times and storage days. The fifty six flavor compounds in Dutch coffee were identified using a headspace mass-spectrometer. Major flavor compounds were 2-furfuryl acetate, 5-methylfurfural, pyridine, furfural, 2-acetylfuran, pyridine, 2-methoxyphenol, furfuryl alcohol and some compounds varied with espresso and drip coffee. It was worthy of notice that more diverse compounds were composed of total flavor in Dutch coffee. There were more kinds of flavor compounds in early extracts than in latter ones. The duration of storage didn't significantly affected the peak area percentage of flavor compounds in Dutch coffee except with 2-furfuryl acetate.

• 한국식품영양학회지
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• 제12권4호
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• pp.375-379
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• 1999

Volatile components of Cornsilk(Zea mays L.) were isolated by purge and trap headspace method and were analyzed by GC and GC/MSD. A total of 44 components were identified in the cornsilk volatile coponents including 9 alcohols 7 aldehydes and ketones 14 terpenes and terpene alcohols 3 pyrazines 5 hydrocarbons and 6 miscellaneous components. The major components were 2-propanol(8.08%) pen-tanol(1.82%) hexanol(2.86%) hexanal(3.68%) heptanal(7.40%) nonanal(7.93%) decanal (2.04%) $\alpha$-copaene(2.20%) limonene(1.68%) $\alpha$-selinene(1.03%) $\beta$-selinene(1.03%)

• Journal of Ginseng Research
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• 제21권3호
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• pp.196-200
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• 1997

The headspace volatiles of the Korean ginseng and the Chinese ginseng were extracted using the SepPak Cl8 cartridge (Wasters Co.) and were analyzed using GC/MSD. The overall GC pattern of the headspace volatiles of the Chinese ginseng was similar to that of the Korean ginseng, but the composition ratios of the two major components, $\beta$-panasinsene to $\beta$-muurolene, were quite different between them. The composition ratios of $\beta$-panasinsene to $\beta$-muurolene of the Korean red and white ginseng were 1.02$\pm$0.28 (n=19) and 1.49$\pm$0.55 (n=14) , respectively. However the com- position ratios of the Chinese red and dried ginseng were 0.58$\pm$0.19 (n=41) and 0.57$\pm$0.17 (n=28), repetitively, which were significantly lower than those of the Korean ginseng at I% level. The composition ratio of the two major headspace volatile components, $\beta$-panasinsene to ${\gamma}$-muurolene, is thought to be as a useful indicator for differentiating the Chinese ginseng with the Korean ginseng.

• Mass Spectrometry Letters
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• 제4권1호
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• pp.18-20
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• 2013

Headspace solid phase micro-extraction gas chromatography/flame ionization detection (HS-SPME-GC/FID) method was compared with headspace gas chromatography/mass selective detection (HS-GC/MS). Organic solvent-spiked urine as well as urine samples from workspace was analyzed under optimal condition of each method. Detection limit of each compound by HS-SPME-GC/FID was $3.4-9.5{\mu}g/L$, which enabled trace analysis of organic solvents in urine. Linear range of each organic solvent was $10-400{\mu}g/L$, with fair correlation coefficient between 0.992 and 0.999. The detection sensitivity was 4 times better than HS-GC/MS in selected ion monitoring (SIM) mode. Accuracy and precision was confirmed using commercial reference material, with accuracy around 90% and precision less than 4.6% of coefficient of variance. Among 48 urine samples from workplace, toluene was detected from 45 samples in the range of $20-324{\mu}g/L$, but no other solvents were found. As a method for trace analysis, SPME HS GC/FID showed high sensitivity for biological monitoring of organic solvent in urine.

• 한국환경과학회지
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• 제13권10호
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• pp.903-909
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• 2004

A new method based on solid phase microextraction(SPME), coupled with GC/FID, has been developed for the determination of PCE and TCE in water samples. The experimental parameters affecting the SPME process (i.e, kinds of fibers, extraction time, desorption time, extraction temperature, volume ratio of sample to headspace, salt addition, and magnetic stirring) were optimized. The coefficients of determination ($R^2$) for PCE and TCE were 0.9951 and 0.9831, respectively when analytes concentration ranges from 10 to 300$\mu$g/L. The relative standard deviations were 3.4 and $2.1\%$ for concentration of 10$\mu$g/L(n=5), respectively. The detection limits of PCE and TCE were 0.5 and l.3$\mu$g/L, respectively.

• Elastomers and Composites
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• 제54권3호
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• pp.188-200
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• 2019

Rubber articles contain various organic additives such as antidegradants, curing agents, and processing aids. It is important to extract and analyze these organic additives. In this paper, various extraction methods of organic additives present in rubber composites were introduced (solvent extraction, Soxhlet extraction, headspace extraction, and solid-phase microextraction), and the extracts were characterized using gas chromatography/mass spectrometry (GC/MS). Solvent and Soxhlet extractions are easy-to-perform and commonly used methods. Efficiency of solvent extraction varies according to the type of solvent used and the extraction conditions. Soxhlet extraction requires a large volume of solvent. Headspace sampling is suitable for extracting volatile organic compounds, while solid-phase extraction is suitable for extracting specific chemicals. GC/MS is generally used for characterizing the extract of a rubber composite because most components of the extract are volatile and have low molecular weights. Identification methods of chemical structures of the components separated by GC column were also introduced.

• Bulletin of the Korean Chemical Society
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• 제33권5호
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• pp.1693-1698
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• 2012

A headspace gas chromatographic mass spectrometric (GC-MS) assay method was developed for the simultaneous determination of methyl tertiary butyl ether (MTBE), $tert$-butyl alcohol (TBA) and benzene, toluene, ethyl benzene and xylene (BTEX) in soil contaminated with gasoline. 2 g of soil sample were placed in a 10 mL headspace vial filled with 5 mL of phosphoric acid solution (pH 3) saturated with NaCl, and the solution was spiked with fluorobenzene as an internal standard and sealed with a cap. The vial was heated in a heating block for 40 min at $80^{\circ}C$. The detection limits of the assay were 0.08-0.12 ${\mu}g$/kg for the analytes. For five independent determinations at 10 and 50 ${\mu}g$/kg, the relative standard deviations were less than 10%. The method was used to analyze fifty six soil samples collected from various regions contaminated with gasoline in Korea. The developed method may be valuable for the monitoring of the analytes in soil.

• 분석과학
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• 제20권6호
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• pp.488-495
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• 2007

본 연구에서는 headspace-solid phase microextraction(HS-SPME)-GC/MS법을 이용하여 PVC 벽지의 원자재에서 방출되는 TVOC를 분석하여 기여도를 평가하였다. 시료로 사용한 원자재는 6종으로 희석제, 안정제, 가소제, 충전제, 발포제와 PVC 레진이다. 각 원자재 시료를 22 mL 바이알에 9 mL씩 취한뒤 $100^{\circ}C$에서 1시간동안 평형을 이룬 다음 $75{\mu}m$ Carboxen-PDMS 화이버로 $25^{\circ}C$에서 1시간 흡착하여 GC/MS로 분석하였다. 정성결과 toluene, ethylbenzene 그리고 xylene과 같은 방향족 화합물과 acetone, methoxyacetone, 2-butanone 등의 케톤류와 nonane, decane, undecane 등의 알켄류가 검출되었다. 그 밖에도 ethanol, butanol 등의 알콜류와 알데히드류 등이 검출되었다. TVOC 방출량은 희석제 $54.20{\mu}g/g$, 안정제 $32.88{\mu}g/g$, 가소제 $0.50{\mu}g/g$, PVC 레진 $0.88{\mu}g/g$, 발포제 $0.22{\mu}g/g$, 충전제가 $0.11{\mu}g/g$로 나타났다. 각 원자재의 TVOC 방출량과 배합비를 고려한 TVOC 기여도는 희석제 0.708, 안정제 0.129, PVC 레진 0.115 순으로 높게 나타났다. 따라서 희석제와 안정제, PVC레진의 질적인 개선을 통해 TVOC 방출량을 줄이는 노력이 필요하다. 또한 본 연구에서 개발한 HS-SPME-GC/MS 방법은 원자재의 TVOC 분석에 유용하게 사용될 것으로 생각된다.

• 약학회지
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• 제54권6호
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• pp.429-440
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• 2010

HS-SPME-GC/MS was studied and optimized for the determination of 17 orgarnophosphorous pesiticides (OPPs: chlorpyrifos, chlorpyrifos-methyl, demeton-s-methyl, diazinon, dimethoate, EPN, fenitrothion, fenthion, malathion, methidathion, monocrotophos, parathion, phenthoate, phosphamidon, sulfotep, terbufos, triazophos) in blood. Optimum SPME parameters were selected: choice of SPME fiber (85 ${\mu}m$ polyacrylate), pH effect (0.5 N HCl), salt effect ($Na_2SO_4$, 0.2 g; 20%), headspace incubation temperature ($80^{\circ}C$), headspace incubation time (1 min), headspace adsorption time (30 min) and GC desorption time (2 min). These parameters were optimized using HS-SPME autosampler coupled with gas chromatography-mass spectrometry (GC-MS). Method validation was carried out in terms of linearity, limit of detection (LOD), limit of quantitation (LOQ) and recovery in blood. The assay was linear over 0.5~5.0 mg/l ($r^2$=0.955~1.000). Limit of detection (LOD) and limit of quantitation (LOQ) in blood were determined 0.03~0.3 mg/l (S/N=3) and 0.1~1.1 mg/l (S/N=10), respectively. Relative recovery with 0.5, 1 and 5 mg/l (in blood) were 90.8%, 98.5% and 94.1%, respectively. This method will be applied to the determination of the orgarnophosphorous pesticides in postmortem blood. The proposed protocol can be an attractive alternative to be used in routine toxicological analysis.