• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.136-143
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• 2006

This study was conducted to determine the amount of unprotonated nicotine in cigarette mainstream smoke and to investigate its relationship to level of filter ventilation and machine smoking conditions. Unprotonated nicotine from TPM trapped on a Cambridge filter pad(CFP) was adsorbed by Carboxen/PDMS SPME fiber, thermally desorbed and determined by GC/MS. 2R4F reference cigarette, twelve commercial brands from the Korean market and five test cigarette samples, which had the same tobacco blend with different levels of filter ventilation, were analyzed for unprotonated nicotine. In commercial brands, the amount of unprotonated nicotine changed slightly depending on the pH values of smoke, and decreased as the tar level increased. filter ventilation in these commercial cigarettes was $28{\sim}80%$ and the higher filter ventilation increased relative unprotonated nicotine levels, but not significantly. However, in five test cigarettes with different filter ventilation$(0{\sim}70%)$, unprotonated nicotine levels increased almost linearly with the level of filter ventilation. Concentrations of unprotonated nicotine in mainstream smoke generally increased in order $HC\;<\;ISO\;{\leq}\;MDPH$ machine smoking conditions. The ratio of unprotonated nicotine to total nicotine among $cigarettes({\alpha}_{fb})$ increased in order RC < MDPB < ISO conditions. Concentrations of unprotonated nicotine varied with three machine smoking conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.866-873
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• 2007

To analyze and differentiate volatile compounds of 13 extra virgin olive oils from market, solid-phase micro extraction (SPME) GC-MS and electronic nose (EN) equipped with metal oxide sensors were applied. The volatiles identified in extra virgin olive oils include hexanal, 4-hexen-1-ol, (Z)-3-hexen-1-ol, acetic acid, and 2,4-dimethyl-heptane, etc. Response from EN was analysed by the principal component analysis. Proportion of the first Principal component was 99.70%, suggesting that each aroma pattern of the 13 extra virgin olive oils could be discriminated by EN. Fatty acid compositions were oleic (61.1${\sim}$77.9 mole%), palmitic (11.7${\sim}$16.5 mole%), linoleic (4.7${\sim}$9.7 mole%), stearic (2.5${\sim}$2.9 mole%), Palmitoleic (0.8${\sim}$2.4 mole%), and linolenic acid (0.7${\sim}$1.2 mole%). In color study, extra virgin olive oil showed $L^{\ast}$ value of 81.7${\sim}$92.9, $a^{\ast}$ value of -28.3${\sim}$13.5 and $b^{\ast}$ value of 52.2${\sim}$139.0. Total phenol and ${\alpha}-tocopherol$ contents were 6.2${\sim}$24.9 mg/100 g and 5.5${\sim}$12.8 mg/100 g, respectively. In Rancimat test, the induction period of 13 extra virgin olive oils showed 31.76${\sim}$54.04 hr while their POV ranged from 13.5 to 22.9 meq/kg oil.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.388-393
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• 2013

It has been well documented that Bacillus vallismortis strain EXTN-1, a beneficial rhizosphere bacterium, could enhance plant growth and induce systemic resistance to diverse pathogens in plants. However, the molecular mechanisms for how the EXTN-1 promote plant growth and induce resistances to diverse pathogens. Here, we show that 3-Hydroxy-2-butanone, a volatile organic compound (VOCs) emitted from the EXTN1, is a key factor for the bacteria-mediated beneficial effects on plant growth and defense systems. We found that the presence of volatile signals of EXTN-1 resulted in growth promotion of tobacco seedlings. The identification and analysis of EXTN-1-secreted volatile signals by solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) indicated that a 3-hydroxy-2-butanone could provide not only the plant growth promotion, but also higher resistance against Pectobacterium carotovorum SCC1. These results suggest that a volatile compound released from EXTN-1 enhances the plant growth promotion and immunity of plants.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1609-1614
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• 2008

To provide scientific information for processing of value-added products from onion, volatile flavor compounds were compared in onions harvested in 6 regions, such as Muan (Jeonnam), Buan (Jeonbuk), Andong (Gyeongbuk), and 3 regions of Gyeongnam around Changnyeong (Yueo, Jangma, Seongsan). A total of 51 compounds were detected in samples by solid phase microextraction (SPME)/GC/MSD and they consisted mainly of sulfur-containing compounds (20), aldehydes (4), ketones (5), esters (11), aromatic hydrocarbons (4), nitrogen containing compounds (2), and miscellaneous compounds (5). The sulfur-containing compounds were the major compounds with ranges of $62.6{\sim}80.3%$ of total volatiles, regardless of harvested regions. The amounts of 5 sulfur containing compounds known as having antioxidant activity (2,4-, 2,5-dimetylthiophene, 2-vinyl-1,3-dithiane, 5-methoxy thiazole, and 3,5-diethyl-1,2,4-trithiolane) were the highest in Andong and followed by Yueo, Jangma, Buan, Seongsan, and Muan. However, onions from Buan region had the highest amounts of 5 sulfur-containing compounds known as having anticarcinogenic activity ((Z)-, (E)-methyl propenyl disulfide, (Z)-, (E)-propenyl propyl disulfide, and di-2-propenyl disulfide), followed by Yueo, Andong, Jangma, Seongsan, and Muan.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1755-1761
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• 2016

Volatile flavor compounds in soy sauce residue (SSR) and acid hydrolysate of SSR (AHSSR) were analyzed by solid phase micro extraction (SPME)/gas chromatography (GC)/mass spectrometry (MSD) methods. A total of 79 compounds were detected in samples (66 SSR and 60 AHSSR). Quantitatively, alcohols (433.37 ng/g), aldehydes (273.01 ng/g), esters (236.80 ng/g), and aromatic hydrocarbons (180.66 ng/g) were dominant in the volatiles of SSR, whereas furans (249.27 ng/g) were only dominant in AHSSR (P<0.05). Among these, four esters, 3-methylbutyl acetate (banana/pear-like), ethyl 3-methyl butanoate (fruity), ethylbenzene acetate (wine-like), and ethyl 3-methyl butanoate (apple-like), three alcohols, 3-methyl-1-butanol (fruity/whisky-like), 2-phenylethanol (floral/sweet), and 1-octen-3-ol (mushroom-like), four aldehydes, (E)-2-phenyl-2-butenal (chocolate-like), benzaldehyde (almond-like), 3-methylbutanal (malty), and 2-phenylacetaldehyde (floral), four aromatic hydrocarbons, 4-ethyl-2-methoxyphenol (smoky/soy sauce-like), 4-ethylphenol (medicine-like), 4-vinyl-2-methoxyphenol (woody), and phenol (woody), and two furans, furfural (almond-like) and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like), were major compounds in SSR, whereas seven compounds, including furfural, 5-methylfurfural (almond-like), 3-methyl-1-butanol, 2-phenylethanol, 4-ethyl-2-methoxyphenol, 3-methylbutanal, and benzaldehyde were major compounds in AHSSR.

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.356-361
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• 2018

It is common to analyze volatile organic compound (VOC) or semi-VOC (SVOC) in a sample composed of a complex matrix consisting of multiple components such as bloods through a separation process. Adsorption is a physical phenomenon in which certain components accumulate on the surface of other phases. In order to overcome difficulties in the pretreatment process, an adsorption is frequently used. Solid phase microextraction (SPME) equipment with porous carbon carboxen (CAR) is an example of adsorption application. In this study, the adsorption of 4-octylphenol to carboxen was examined. To do so, the extraction efficiency for such solvents as dichloromethane ($CH_2Cl_2$, DCM), ethylacetate ($CH_3COOC_2H_5$, EA) and diethylether ($C_2H_5OC_2H_5$, $Et_2O$) was studied and also the derivatization reaction for 4-octylphenol with reagents of bistrimethylsilyltrifluoroacetamide (BSTFA), methylchloroformate (MCF) and pentafluorobenzylbromide (PFBBr) was compared. The combination of DCM and BSTFA showed good performance thus they were adopted for this study. Thermodynamic adsorption experiments showed that the adsorption process was endothermic and Freundlich isotherm equation was more suitable than Langmuir isotherm. It was also found that the adsorption followed a pseudo-$2^{nd}$ order kinetic model.

• Analytical Science and Technology
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• v.10 no.4
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• pp.264-273
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• 1997

Anodic oxidation reaction was applied to remove trihalomethanes in an aqueous solution. Each component was determined by using solid phase microextraction(SPME) fiber and GC-ECD. Anodic and cathodic compartments were separated in order to protect contaminants and connected by $KNO_3$-agar bridge. The calibration graphs of the 6 THM components were shown good linearlity from a few ppb up to a few hundreds ppb concentration level. Anodes such as platinum(Pt), titanium(Ti). zircornium(Zr), titanium metal coated with iridium(Ti-Ir), and glassy carbon coated with mixed valence ruthenium(mv Ru) were tried to remove the THMs at different potentials. The best result was obtained on the Ti-Ir anode applied 9 volts DC. The electrode could effectively remove almost all the THM components from the stirring solution within about 1.5 hours. The glassy carbon electrode coated with mixed valence ruthenium showed excellent removing effect at the begining, but the maximum removing level was remained at 60% probably due to the destruction of the electrode surface. The concentration of chloroform, however, tends to be increased due to the electrode reaction producing the component at the condition.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.324-329
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• 2019

Volatile flavor compounds of radish fermented by lactic acid bacteria were extracted using solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 45 volatile flavor compounds were identified. The volatile flavor compounds in unfermented radish mostly consisted of sulfur-containing compounds (95.85%) and aldehydes (2.61%). While the composition ratio of volatile flavor compounds in radish fermented for two days changed to sulfur-containing compounds (75.53%) and acids (11.12%). As the fermentation period was increased, the contents of dimethyl disulfide, dimethyl trisulfide, diallyl sulfide, diallyl disulfide, and diallyl trisulfide, which have unique garlic and scallion flavor, decreased, and acetic acid and 1-hexanol, which have a sour and fruity flavor, increased. These changes in volatile flavor compounds seemed to have affected the flavor characteristics of fermented radish.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.393-398
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• 2020

The blueberry gall midge, Dasineura oxycoccana (Johnson) (Diptera: Cecidomyiidae), is an emerging pest on cultivated blueberries in Korea. To develop a sensitive tool for monitoring this pest in blueberry orchards, we compared the attractiveness of host plant volatiles and sex pheromone to D. oxycoccana adults. We performed gas chromatography-mass spectrometry (GC-MS) analysis of solid-phase microextraction (SPME)-collected volatiles that were released from blueberry ('Darrow' cultivar). The analysis revealed two major volatiles, cinnamaldehyde and cinnamyl alcohol from flowers; and three major volatiles, β-caryophyllene, germacrene D, and α-farnesene from shoots and young fruits. In field tests conducted in Gunsan, Korea in 2019, commercialized cinnamaldehyde, cinnamyl alcohol, β-caryophyllene, and α-farnesene, used singly or in quaternary combination, were unattractive to the blueberry gall midge. However, traps baited with the known sex pheromone (2R,14R)-2,14-diacetoxyheptadecane attracted significantly more males than the treatments with plant volatiles or the control. No synergistic effect was observed between sex pheromone and plant volatiles. Male D. oxycoccana were captured in the pheromone traps from May to August, with three peaks in mid-May, late June, and late July in Gunsan blueberry fields in 2020.

• Journal of Apiculture
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• v.34 no.3
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• pp.189-195
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• 2019

Plants release a large variety of volatile organic compounds (VOCs) into the surrounding atmosphere. Floral volatile compounds (FVCs) emitted from many plants is the critical factors for pollinator attraction and defense for adaptation in environments. Recent studies indicate that the chemical components contributing to FVCs play an important role in the honeybee attractiveness to flowers. Olfactory signals are rapidly learned, indicating that foraging behavior results from the association of plant chemicals acting as chemosensory cues for the bees. Solid phase microextraction(SPME)-GC/MS method was applied to analyze the chemical composition of FVCs according to the different species of Robinia spp. The abundant compounds identified in R. pseudoacacia were (Z)-β-ocimene (34.86%) and linalool (35.47%). Those of the tetraploid R. pseudoacacia were (Z)-β-ocimene (35.42%) and α-Farnesene (33.94%). The volatiles of R. margarettae 'Pink Cascade' comprised an abundance of (Z)-β-ocimene (42.73%), (E)-4,8-Dimethylnona-1,3,7-triene (37.23%). Differences in FVCs of the different species of Robinia spp. are discussed in light of biochemical constraints on volatile chemical synthesis and of the role of flower scent in ecology of pollination.