• Journal of the Korean Society of Tobacco Science
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• v.30 no.2
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• pp.117-124
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• 2008

A solid phase microextraction (SPME) method in combination with gas chromatography/mass spectrometric techniques was used for the extraction and quantification of 12 selected agrochemical residues in tobacco. The parameters such as the type of SPME fiber, adsorption/desorption time and the extraction temperature affecting the precision and accuracy of the SPME method were investigated and optimized. Among three types of fibers investigated, polyacrylate (PA), polydimethylsiloxane (PDMS) and polydimethylsiloxane-divinylbenzene (PDMS-DVB), PDMS fiber was selected for the extractions of the agrochemicals. The SPME device was automated and on-line coupled to a gas chromatograph with a mass spectrometer. Mass spectrometry (MS) was used and two different instruments, a quadrupole MS and triple quadrupole MS-MS mode, were compared. The performances of the two GC-MS instruments were comparable in terms of linearity (in the range of 0.01$\sim$0.5 $\mu$g/mL) and sensitivity (limits of detection were in the low ng/mL range). The triple quadrupole MS-MS instrument gave better precision than that of quadrupole MS system, but generally the relative standard deviations for replicates were acceptable for both instruments (< 15%). The LODs was fully satisfied the requirements of the CORESTA GRL. Recoveries of 12 selected agrochemicals in tobacco yielded more than 80% and reproducibility was found to be better than 10% RSD so that SPME procedure could be applied to the quantitative analysis of agrochemical residues in tobacco.

• Mass Spectrometry Letters
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• v.8 no.1
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• pp.18-22
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• 2017

Products containing any one or more of 26 fragrance allergens likely to cause contact allergies, are required under the 2008 domestic cosmetic law to be labeled when their concentrations exceed a certain range. This study focuses on the comparison and development of analytical methods based on headspace-solid phase micro extraction (HS-SPME) and liquid-liquid extraction (LLE) methods followed by GC-MS/MS for 24 of the fragrance allergens excepting for two natural materials in water samples. Using the developed HS-SPME method, 15 of the 24 fragrance allergens were analyzed and 9 compounds which have relatively low $logK_{OW}$ values (below about 2.5) were not extracted, and the correlation coefficient ($r^2$) of the calibration curve for quantification showed linearity of 0.9969 or more, and the method detection limits (MDL) and the limits of quantification (LOQ) were $0.078{\sim}0.582{\mu}g/L$ and $0.261{\sim}1.940{\mu}g/L$, respectively. In the case of using the optimized LLE method, all 24 fragrance allergens were analyzed, and the correlation coefficient ($r^2$) of the calibration curve for quantification showed linearity of 0.9957 or more, MDL and LOQ were $0.020{\sim}0.138{\mu}g/L$ and $0.065{\sim}0.440{\mu}g/L$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.874-880
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• 2007

Volatile flavor compounds of 4 grape species (Campbell, Sheridan, Red globe, and Meoru) were identified during 3-day storage at either $4^{\circ}C$ or room temperature. Each sample was analyzed by solid-phase micro-extraction (SPME) method combined with gas chromatography-mass spectrometry. Also electronic nose composed of 12 different metal oxide sensors was used to differentiate flavors of grapes. Sensitivities (delta $R_{gas}/R_{air}$) of sensors from electronic nose were obtained by principal component analysis (PCA). Proportion of the first principal component was 99.30% at $4^{\circ}C$ and 99.36% at room temperature, respectively. In our result, flavor patterns of grape can be differentiated according to the storage period. The major volatile flavor compounds were 1-hexanol, hexanoic acid and its ethyl ester, and phenylethyl alcohol with the presence of butanoic acid and its ethyl ester, acetic acid, benzeneacetic acid and its ethyl ester.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.246-254
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• 2007

Fresh tea leaves grown in Jeju Island and Jeonnam Province of South Korea were plucked and processed. Volatile compounds (VCs) were analyzed and identified with SPME-GC/GC-MS/GC-O. The VCs of green teas were classified into two major categories based on their aroma characteristics: the Greenish (Group I), and Floral (Group II) odorants. It was found that the VCs were decreased significantly in fresh tea leaves as they were plucked at the later stages of cultivation. The ratio of VCs responsible for Group I and Group II compounds was well-balanced in tea leaves plucked in May, but the balances were changed when the fresh leaves were processed. The major VCs of fresh tea leaves in Jeju and Jeonnam were n-hexanal, E-2-hexenal, Z-3-hexenal, myrcene, benzyl alcohol, linalool, and phenyl alcohol. Also, Jeju and Jeonnam tea leaves had different aroma composition. n-Heptanol, ${\beta}-pinene$, benzaldehyde, and ethyl salicylate were found in Jeju fresh tea leaves, and Z-3-hexenol, E-2-hexenol, and methyl n-heptanoate were detected in Jeju dry tea leaves. On the other hand, Z-linalool oxide and myrcene were found in Jeonnam dry tea leaves. The SPME-GC method showed high reproducibility (RSD, 7.4%) with no-artifact formation. In this study, optimum plucking period of tea leaves could be determined for production of high quality green tea with a well-balanced aroma and characteristic VCs in green tea according to growing areas.

• Analytical Science and Technology
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• v.14 no.1
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• pp.44-49
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• 2001

Solid-phase microextraction (SPME) with $85{\mu}m$ polyacrylate fiber, coupled to gas chromatography-mass spectrometry was used to analyze the plasticizers contained in balloon samples. The balloons were identified to be made of polyisoprene by IR spectroscopy. The plasticizers extracted from the balloon samples soaked in acetone-added water solvent for an hour were quantified by external standard method using nine kinds of plasticizers. The quantification method was validated for standard plasticizers in the range of $0.25-25{\mu}g/g$. The detection limits were $0.11-0.38{\mu}g/g$ for different plasticizers. The RSDs for the reproducibility of this quantitation method were 3.7-14.2%. A few of balloons included risky level of plasticizer concerned as and endocrine disrupter, and it is necessary to regulate these products.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.507-512
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• 2000

The headspace flavors of roasted tea, prepared with steamed and nonsteamed polygonatum roots, were absorbed in solid-phase microextraction(SPME) fiber coated with $65\;{\mu}m$ of carbowax/divinylbenzene(CW/DVB) and analysed by GC-MS. The absorption conditions of SPME fiber for equilibrated headspace were selected as $60^{\circ}C$ and 30 min. In a comparison for both samples roasted at $130^{\circ}C$ for 15 min, gas chromatograms showed a similar pattern in overall profiles between steamed and nonsteamed samples before roasting, but some differences were observed in peak characteristics. From 40 separated peaks, 25 compounds were identified with both GC-MS and retention time comparison. The pyrazines including 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, 2,5-dimethyl-4-hydroxy-3(2H)-furanone, 2-acetyl-1-pyrroline, etc. were higher in their contents in nonsteamed-roasted sample than steamed-roasted one. In particular, steamed-roasted polygonatum showed higher contents of acetic acid(8.17%) and hexanoic acid(5.43%) than the corresponding compounds of nonsteamed-roasted one, 2.40% and 2.00%.

• Analytical Science and Technology
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• v.30 no.2
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• pp.68-74
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• 2017

The volatile components in 'Fuji' apple were effectively determined by a headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS). A total of 48 volatile components were identified and tentatively characterized based on National Institute of Standards and Technology (NIST) MS spectra library and the Kovats GC retention index I (RI). The harvested Fuji apples were divided into two groups: 1-methylcyclopropene (1-MCP) treated and non-treated (control) samples for finding important indicators between two groups. The major volatile components of both apples were 2-methylbutyl acetate, hexyl acetate, butyl 2-methylbutanoate, hexyl butanoate, hexyl 2-methylbutanoate, hexyl hexanoate and farnesene. No significant differences of these major compounds between 1-MCP treated and non-treated apples were observed during 1 month storage. Interestingly, the amount of off-flavors, including 1-butanol and butyl butanoate, in 1-MCP treated apples decreased over 5 months, and then increased after 7 months. However, non-treated apples did not show significant changes for off-flavors during 7 month storage (p<0.05). The non-treated apples also contained the higher levels of two off-flavors than 1-MCP treated apples. These two compounds, 1-butanol and butyl butanoate, can be used as quality indicators for the quality evaluation of Fuji apple.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.234-239
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• 2005

본 연구는 재래흑돼지육의 진공포장 숙성중 지방산 조성과 SPME-GC/MS에 의한 향기성분을 구명하고자 실시하였다. 지방산 조성으로 C14:0, C16:1n7은 재래흑돼지육이 개량종 돼지육보다 낮았으며(p<0.05), C18:1n7, C22:4n6는 재래흑돼지육이 높았다(p<0.05). 숙성기간 동안 향기성분은 숙성 0일에 2-decanone, 2-ethyl hexanol, hexa -noic acid가 재래흑돼지육에서만 검출되었으며, 숙성 6, 12일에는 butanoic acid, 2.3-butanediol, benzen -acetaldehyde, benzeneethanol, 2-hexadecal, hexanoic acid가 재래흑돼지육에서만 검출되었다.

• Journal of Environmental Science International
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• v.22 no.12
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• pp.1539-1549
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• 2013

The purpose of this study is to compare the sampling methods for monitoring indoles (phenol, p-cresol, indole and skatole) in airs of swine facility. As the collecting methods of indoles in air, Tenax-TA adsorption tube and solid phase microextraction (SPME) were examined. For the preparation of calibration curves of indoles concentrated in Tenax-TA, the standard indoles solutions were spiked in each of Tenax-TA tubes and thermally desorbed (ATD) into a gas chromatograph combined with mass detector (GC/MS). And for the preparation of calibration curves by SPME, indoles in the standard gaseous solution prepared by evaporating the aqueous solution that contained indoles into a polyester sampling bag were extracted with SPME fiber and subsequently analyzed by the GC/MS. Two sampling methods were evaluated for extracting indoles present in swine building environments. Results indicated that the SPME method using Polydimethylsiloxane/ Divinylbenzene (PDMS/DVB) fiber was more effective than Tenax-TA method in extracting indoles. The gas chromatographic analysis showed that the linearities of calibration curves and detection limits were useful for detection of indoles in swine airs. The field tests also showed that considerably different levels of indoles were present in various parts of the swine building.

• Food Science and Preservation
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• v.13 no.2
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• pp.269-272
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• 2006

Aroma compounds in chungkukjang with Astragalus membranaceus (Hwangki) were extracted by the simultaneous distillation and extraction (SDE), headspace and solid phase microextraction (SPME), and aroma compounds obtained by this method were identified with GC-MS. Thirty compounds were identified, including six ketones, eight alcohols, three heterocyclic compounds, three aldehydes, five hydrocarbones and five other compounds. Major aroma compounds were identified as 3-hydroxy-2-butanone, 2-furanmethanol, 2-methoxy-4-vinylphenol, and 4-vinylphenol in SDE, 2,3-butanedione, 3-hydroxy-2-butanone, ethanol, 2,6-dimethyl pyrazine and acetic acid in headspace and acetone, ethanol, 2,5-dimethyl pyrazine, tetramethyl pyrazine and acetic acid in SPME. The content of pyrazines identified in headspace and SPME methods was higher than that of SDE method, and the content of pyrazines containing 2,5-dimethyl pyrazine, 2,6-dimethyl pyrazine and tetramethyl pyrazine in chungkukjang was higher than that of Hwangki chungkukjang.