• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.6
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• pp.437-440
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• 2006

To develop natural crab-like flavorants from red snow crab Chionoecetes japonicus cooker effluent (RSCCE), the flavor was analyzed during the concentration of RSCCE up to $40^{\circ}Brix$. Using solid phase microextraction (SPME)/gas chromatography (GC)/mass selective detection (MSD), 30 volatile flavor compounds were detected in four RSCCE samples (10, 20, 30, and $40^{\circ}Brix$). These comprised 12 aromatic compounds, 5 N-containing compounds, 2 5-containing compounds, 2 alcohols, 2 aldehydes, and 7 miscellaneous compounds. The amounts of all volatiles except alcohols and aldehydes increased significantly with the concentration (p<0.05). Of the volatiles detected, the most abundant was a dimethyl trisulfide with an odor like onion/cooked cabbage. Of the N-containing compounds (nutty, roasted peanut-like odor), 2-ethyl-5-methylpyrazine was the most abundant, followed by 2,5-dimethylpyrazine and 2-methyl-5-isopropylpyrazine in that order (p<0.05). The N- and S-containing compounds with characteristic odors detected in this experiment are thought to play a positive role in RSCCE during concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.953-957
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• 2002

Volatile compounds from shrimp whole body (SWB) and shrimp shell waste (SSW) were isolated, and identified by the combination of SDE (simultaneous steam distillation and solvent extraction), GC (gas chromatography, HP-5890 plus)and MSD (mass selective detecter) or olfactometry. The peak numbers isolated from SWB and SSW were 20 and 46, respectively. The amounts of the volatile compounds isolated from SSW were higher than those of SWB. SWB produced more low-boiling compounds below 7$0^{\circ}C$ and SSW did more high boiling compounds over 10$0^{\circ}C$. The volatile compounds identified from SSW were 9 pyrazines,5 acids,4 aldehydes, and 4 alcohols. These volatile compounds were evaluated by aroma extraction dilution analysis and gas chromatography olfactometry (GCO). Some compounds which were not detected by GC-FID and GC-MSD were found to be a strong shrimp flavor of log$_3$ FD 3 value by GCO. Strong shrimp odors were detected in low temperature while nutty aromatic odors and unpleasant oily smells were found in high temperature.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.669-674
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• 2008

Zanthoxylum schinifolium and Zanthoxylum piperitum A.P. DC. belong to the Rutaceae family and are perennial, aromatic, and medicinal herbaceous plants. In this study, their aroma compounds were isolated by steam distillation extraction using a Clevenger-type apparatus, and then further analyzed by gas chromatography (GC) and gas chromatograph/mass spectrometry (GC/MS). The yields of the essential oils from Z. schinifolium and Z. piperitum AP. DC. were 2.5 and 2.0%(w/w), respectively, and the color of their oils was quite similar, a pale yellow. From the distilled oil of Z. schinifolium, 60 volatile compounds which make up 87.24% of the total composition were tentatively identified, with monoterpenes predominating. $\beta$-Phellandrene (22.54%), citronellal (16.48%), and geranyl acetate (11.39%) were the predominantly abundant components of Z. schinifolium. In the essential oil of Z. piperitum AP. DC., 60 volatile flavor components constituted 94.78% of the total peak area were tentatively characterized. Limonene (18.04%), geranyl acetate (15.33%), and cryptone (8.52%) were the major volatile flavor compounds of Z. piperitum A.P. DC.

• Asian Journal of Atmospheric Environment
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• v.4 no.1
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• pp.42-54
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• 2010

Automobile emissions have caused a major hydrocarbon pollution problem in the ambient air of many cities around the world. This study was conducted to measure the pollution status of volatile organic compounds (VOCs) in some urban residential areas in Seoul, Korea. A total of 20 VOCs (11 aromatic and 9 chlorinated species) were identified at 4 urban residential sites in Seoul, Korea from February 2009 to July 2009. Comparison of total VOC (TVOC) concentration data indicated the dominance of the aromatic species with the maximum (72.2 ppbC) at Jong Ro (JR) and the minimum at Yang Jae (33.4 ppbC). The peak concentration of TVOC occurred during spring at all sites with an exception at Gang Seo (GS), where it was recorded during winter. The distribution of individual VOCs at the study sites was characterized by high toluene concentration. A strong correlation of benzene was also observed with other VOCs and criteria pollutants at all sites (except YJ). The overall results of this study suggest that vehicular emissions have greatly contributed to the increase in VOC pollution at all the study sites.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.1
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• pp.43-62
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• 1998

This study was carried out to investigate the influence of different sampling methods on the measured concentrations of polycyclic aromatic hydrocarbons (PAH) both in the vapor and particulate phases, and to evaluate the effects of ambient temperature and sampling duration on the losses of PAH associated with particle samples due to volatilization. The experimental protocol of this study is consisted of two parts. The first part is related to the comparison of PAH concentrations measured by 4 different sampling systems, each of which involves different sampling principles for comparison purposes, including a medium-volume sampler with XAD-2 adsorbent, a high-volume sampler with polyurethane foam (PUF), two identical low-volume samplers: one with XAD-2 and the other with PUF, respectively. The second part of this study is to quantitatively estimate the losses of particulate PAH samples by volatilization during sampling, using two identical low-volume samplers: one was used for changing the filters every 3 hrs, 6 hrs, 12 hrs, and 24 hrs sampling, while the other was maintained for continuous 48 hours sampling without changing the filter. The concentrations of volatile PAH including 2-3 rings appeared to be significantly affected by the type of adsorbent. Measured levels of these lower-molecular weight PAH by XAD-2 adsorbent were much higher than those by PUF for both high-volume and low-volume sampling. PUF was found to give rise to unknown components that interfered with the PAH analysis, even after extensive clean-up. In addition, the retention efficiency of PUF for lower molecular weight PAH was subject to a large variation, being significantly influenced by sampling conditions such as ambient temperature. However, the effect of sampling methods with different adsorbents on the measured levels of semi-volatile compounds including 4 rings PAH such as fluoranthene, pyrene, BaA and chrysene, was not so much significant as more volatile PAH compounds. It was also clear from this study that volatilization losses of the semi-volatile PAH collected on the filters were inevitably occurred during prolonged sampling, and hence the results obtained from conventional sampling methods may not be expected to yield an accurate distribution of PAH between the vapor and particulate phases.

• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.95-107
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• 2002

This study was designed to investigate the characteristics of atmospheric concentrations of toxic volatile organic compounds (VOCs) in Korea. Target compounds included 1,3-butadiene, aromatics such as BTEX, and a number of carbonyl compounds. In this paper, as the first part of the study, the performance of sampling and analytical methods was evaluated for the measurement of selected VOCs and carbonyl compounds in the ambient air. VOCs were determined by the adsorbent tube sampling and automatic thermal desorption coupled with GC/MSD analysis, while carbonyls by the DNPH-silica cartridge sampling with HPLC analysis. The methodology was investigated with a wide range of performance criteria such as repeatability, linearity. lower detection limits, collection efficiency, thermal conditioning, breakthrough volume and calibration methods using internal standards. In addition, the sampling and analytical methods established in this study were applied to real field samples duplicately collected in various ambient environments. Precisions for the duplicate samples appeared to be comparable with the performance criteria recommended by USEPA TO-17. The overall precision of the sampling and analytical methods was estimated to be within 20 ∼ 30% for major aromatic VOCs such as BTEX, whereas the precision for major carbonyl compounds such as formaldehyde and acetaldehyde was within 10 ∼ 20% for field samples. This study demonstrated that the adsorbent sampling and thermal desorption method can be reliably applied for the measurement of BTEX in ppb levels frequently occurred in common indoor and ambient environments.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.414-418
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• 2008

Volatile compounds in Omangdungi (Styela plicata)-Doenjang (soybean paste) stew were analyzed using solvent-assisted flavor evaporation/gas chromatography/mass-selective detection/olfactometry (SAFE/GC/MSD/O) and aroma extract dilution analysis (AEDA). The GC/O analysis detected 37 volatile compounds, of which 32 were positively identified, and included 9 aldehydes, 5 alcohols, 4 aromatic hydrocarbons, 4 ketones, 3 esters, 3 N-containing compounds, 2 acids, 1 S-containing compound, and 1 furan. Nine aroma-active odorants ($\log_3FD{\geq}3.0$) in the sample included six compounds derived from Doenjang (3-methyl(thio)propanal, tetramethylpyrazine, 4-vinyl-2-methoxyphenol, 2-acetylpyrrole, butyric acid, and 2-methoxyphenol) and three compounds from Omangdungi (2-acetyl-2-thiazoline, 9-decanol, and 6-decenol). Three compounds derived from Omangdungi (9-decanol, 6-decenol, and 6-nonenol) were thought to enhance the seafood-like flavor of Omangdungi-Doenjang stew.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.668-673
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• 2015

The pacific oyster Crassostrea gigas has a desirable taste and flavor that differs from those of other fish and shellfish. In order to develop a high value-added product from individually quick-frozen oyster extract (IQFOE), we prepared an oyster sauce from IQFOE and characterized its volatile compounds using vacuum simultaneous steam distillationsolvent extraction / gas chromatography / mass spectrometry. The moisture, crude protein, crude ash, salinity, pH and volatile basic nitrogen contents of the oyster sauce were 60.6%, 8.2%, 9.2%, 9.3%, 5.7 and 21.0 mg/100 g, respectively. Seventy-six volatile compounds were detected in the cooked odor of the oyster sauce. These volatile compounds included 14 esters, including ethyl acetate, 13 nitrogen- containing compounds, including 2,4,6-trimethyl pyridine, 13 acids, including hexadecanoic acid, 12 alcohols, including ethyl alcohol and 6-methyl heptanol, 6 alkanes, 5 aldehydes, including benzaldehyde, 5 ketones, including 1-(2-furanyl)-ethanone, 4 furans, including 2-furancarboxaldehyde and 2-furanmethanol, 3 aromatic compounds, including d-limonene, and 1 miscellaneous compound. Esters, acids and nitrogen-containing compounds, and alcohols were the most abundant compounds in the odor of the cooked oyster sauce, with some aldehydes, ketones, and furans.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.739-744
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• 1998

Changes of volatile flavor compounds in sesame oil during industrial process (roasting temp. $225{\pm}2^{\circ}C$, roasting time 15 min) were investigated. Total volatile flavor compounds of 1 st expressed oil from roasted sesame seeds were 536.3 ppm, and those of 2nd expressed oil from sesame seed cake, residue of 1st expression, were 266.8 ppm. Those of 1st filtered oil, fixed oil and 2nd filtered oil were 472.2 ppm, 472.4 ppm and 443.0 ppm, respectively. Volatile flavor compounds were gradually decreased during processing. Top notes $(peak{\;}No.1{\sim}26)$ playing an important role in the aromatic character of sesame oil, of 2nd expressed oil were markedly reduced (70.67% of initial content). Especially pyrazine compounds showed the largest reduction in 2nd expressed oil. Total volatile flavor compounds of fixed oil, filtered oil were reduced slightly.

• Research in Plant Disease
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• v.28 no.1
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• pp.1-18
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• 2022

Volatiles exist ubiquitously in nature. Volatile compounds produced by plants and microorganisms confer inter-kingdom and intra-kingdom communications. Autoinducer signaling molecules from contact-based chemical communication, such as bacterial quorum sensing, are relayed through short distances. By contrast, biogenic volatiles derived from plant-microbe interactions generate long-distance (>20 cm) alarm signals for sensing harmful microorganisms. In this review, we discuss prior work on volatile compound-mediated diagnosis of plant diseases, and the use of volatile packaging and dispensing approaches for the biological control of fungi, bacteria, and viruses. In this regard, recent developments on technologies to analyze and detect microbial volatile compounds are introduced. Furthermore, we survey the chemical encapsulation, slow-release, and bio-nano techniques for volatile formulation and delivery that are expected to overcome limitations in the application of biogenic volatiles to modern agriculture. Collectively, technological advances in volatile compound detection, packaging, and delivery provide great potential for the implementation of ecologically-sound plant disease management strategies. We hope that this review will help farmers and young scientists understand the nature of microbial volatile compounds, and shift paradigms on disease diagnosis and management to aromatic (volatile-based) agriculture.