• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.491-502
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• 2003

In the present work, the distribution characteristics of ambient volatile organic compounds (VOCs) were investigated at high temporal resolution from a monitoring station located in a mid-eastern area of Seoul. A total number of 587 samples were collected during December 2002 to January 2003. The measurements of VOC were conducted by a combination of on-line air sampling and thermal desorption unit (TDU) coupled with capillary GC/FID analysis. A total of five aromatic compounds (BTEX: benzene, toluene, ethylbenzene, m, p-xylene, and o-xylene) were measured routinely at hourly intervals during the whole study period. The mean concentrations of BTEX measured in our study period were found in the order: toluene (8.99 $\pm$5.38 ppb) > benzene (0.92$\pm$0.52 ppb) > m, p-xylene (0.51$\pm$0.34 ppb) > 0- xylene (0.48$\pm$0.35 ppb) > ethyl benzene (0.43$\pm$ 0.32 ppb). The BTEX concentrations were generally higher during the daytime than the nighttime, exhibiting certain patterns on a weekly basis. Results of our analysis indicate that the unusually high concentrations of toluene, while showing good correlations with other VOCs, can be a good indicator of air pollution in the study area.

• Journal of the Korean Society of Combustion
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• v.4 no.2
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• pp.23-33
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• 1999

A turbulent non-premixed ethylene flame, which was set up in a vertical wind tunnel, was examined to understand the effect of turbulent mixing on formations of soot and gaseous species in the flames. Temperature and velocity profiles were measured using uncoated thermocouples and LDV system. Gaseous samples were withdrawn by using a water cooled stainless iso-kinetic gas sampling probe. The samples for inorganic compounds and light hydrocarbons were collected with sampling bottles and were analyzed by a gas chromatography. The samples for aromatic hydrocarbons were collected on a sorbent tube and were analyzed on a GC/MS system. Some of main results were followed. CO and $CO_2$ were measured relatively in early part of flame and the concentration of CO was greater than that of $CO_2$ all over the early flame region due to the scavenging of the oxidizing species OH by soot particles. Aromatic hydrocarbons were measured at x/D=122 along the radial direction and main important species were benzene, xylene, toluene, styrene, indene, naphthalene. The peak points of these compounds occurred at r/D=0.8 apart from the center of flame, around in which the concentration of $C_2H_2$ decayed relatively rapidly from the maximum value.

• Journal of the Korean Applied Science and Technology
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• v.24 no.3
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• pp.211-218
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• 2007

Based on the Benzoflex (Vesicol Chemical Co.) as PVC plasticizer substituents for Di-n-octyl phthalate (DOP), a series of new aromatic carboxylic acid ester compounds were designed as plasticizers, synthesized, and screened for the endocrine disrupting activity. 2-Hydroxybenzoic acid (1) and 2-methoxybenzoic acid (2) as the commercially available starting materials were reacted with diethylene glycol (3) in the presence of p-toluenesulfonic acid using Dean-Stark column to give diethylene glycol di-(2-hydroxy)benzoate (4, KH01) and diethylene glycol di-(2-methoxy)benzoate (5, KH02), respectively. And diethylene glycol di-(3-pyridinyl) ester (7, KH03) and dipropylene glycol di-(3-pyridinyl) ester (9, KH04) were obtained in high yields by treatment of nicotinoyl chloride (6) with diethylene glycol (3) and dipropylene glycol (8) in the presence of triethylamine as a base. To determine the estrogenic disrupting effect of new synthetic phthalate analogues, E-screen assay method was used. Of these compounds, 4 (KH01) was found to be compound without endocrine disrupting effect.

• 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.

• Food Science and Preservation
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• v.30 no.6
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• pp.1029-1042
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• 2023

This study aimed to apply the technology of increasing the volatile aromatic compounds in wine through mixed fermentation of Saccharomyces cerevisiae and non-Saccharomyces yeasts to make distilled soju. The expectation was to induce changes in metabolites such as volatile aromatic compounds before the distillation process, followed by concentrating these compounds through distillation to enhance the odor property of distilled soju. Additionally, the study aimed to examine the impact of mixed fermentation with S. cerevisiae and non-Saccharomyces yeasts on distilled soju's free amino acid content. As a result, when Hanseniaspora uvarum yeast was used, there was an increase in the content of low molecular weight volatile aroma compounds, particularly esters. Distilled soju co-fermented with S. cerevisiae and H. uvarum SJ69 exhibited similar amino acid content to distilled soju single-fermented with S. cerevisiae. However, distilled soju co-fermented with S. cerevisiae and H. uvarum S6, a decrease in amino acid content. Sensory evaluation results indicated a higher odor score in distilled soju co-fermented with S. cerevisiae and H. uvarum S6, suggesting that the mixed fermentation technology utilizing H. uvarum could contribute to improving the quality of distilled soju in the future.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1164-1166
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• 2009

Aromatic aldehydes are efficiently self-condensed into $\alpha$-hydroxy carbonyl compounds by polystyrene-supported ammonium cyanide as an excellent organocatalyst in C-C bond formation. The reaction proceeds in water under mild reaction conditions. The polymeric catalyst can be easily separated by filtration and reused several times without appreciable loss of activity.

• Biomolecules & Therapeutics
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• v.31 no.1
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• pp.108-115
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• 2023

Numerous psychotropic and addictive substances possess structural features similar to those of β-phenethylamine (β-PEA). In this study, we selected 29 β-PEA derivatives and determined their structure-activity relationship (SAR) to their ability to inhibit dopamine (DA) reuptake; conducted docking simulation for two selected compounds; and identified their potential functionals. The compounds were subdivided into arylethylamines, 2-(alkyl amino)-1-arylalkan-1-one derivatives and alkyl 2-phenyl-2-(piperidin-2-yl)acetate derivatives. An aromatic group, alkyl group, and alkylamine derivative were attached to the arylethylamine and 2-(alkyl amino)-1-arylalkan-1-one derivatives. The inhibitory effect of the compounds on dopamine reuptake increased in the order of the compounds substituted with phenyl, thiophenyl, and substituted phenyl groups in the aromatic position; compounds with longer alkyl groups and smaller ring-sized compounds at the alkylamine position showed stronger inhibitory activities. Docking simulation conducted for two compounds, 9 and 28, showed that the (S)-form of compound 9 was more stable than the (R)-form, with a good fit into the binding site covered by helices 1, 3, and 6 of human dopamine transporter (hDAT). In contrast, the (R, S)-configuration of compound 28 was more stable than that of other isomers and was firmly placed in the binding pocket of DAT bound to DA. DA-induced endocytosis of dopamine D₂ receptors was inhibited when they were co-expressed with DAT, which lowered extracellular DA levels, and uninhibited when they were pretreated with compound 9 or 28. In summary, this study revealed critical structural features responsible for the inhibition of DA reuptake and the functional role of DA reuptake inhibitors in regulating D₂ receptor function.

• Natural Product Sciences
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• v.24 no.3
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• pp.139-147
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• 2018

The essential oils are fragrant products whose complex compositions are obtained from various parts of plants by dry or steam distillation. Plants with variable biological activities have been explored worldwide. The presence of a large number of phenols, terpenes and other aromatic compounds make essential oils more precise in their mode of action. Because of this, they are known to possess many biological activities like antimicrobial, antioxidant and anti-inflammatory etc. In this article, we will review the published literature summarizing the chemistry of essential oils and their important biological activities.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.434-437
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• 2000

Streptomyces setonii(ATCC 39116) is a thermophilic gram-positive soil bacteria which undergoes an ortho-cleavage pathway in the presence of phenol or benzoate as a sole carbon and energy source. The specific activities of catechol-1,2-dioxygenase in S. setonii, a key enzyme in ortho-cleavage pathway, were induced by various aromatic compounds such as benzoate, phenol, m-hy-benzoate, p-hy-benzoate, catechol, o-cresol, m-cresol, p-cresol, benzene, toluene, ethyl-benzene, 2-chloro-phenol, and 4-chloro-phenol, among which the phenol showed the highest inducibility in the presence of 0.01% glucose. More than 0.1% glucose dramatically reduced the specific activities of catechol-1,2-dioxygenase induced by most of the single aromatic compounds tested.

• Toxicological Research
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• v.32 no.2
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• pp.89-93
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• 2016

Human cytochrome P450 enzymes (P450s, CYPs) are major oxidative catalysts that metabolize various xenobiotic and endogenous compounds. Many carcinogens induce cancer only after metabolic activation and P450 enzymes play an important role in this phenomenon. P450 1B1 mediates bioactivation of many procarcinogenic chemicals and carcinogenic estrogen. It catalyzes the oxidation reaction of polycyclic aromatic carbons, heterocyclic and aromatic amines, and the 4-hydroxylation reaction of $17{\beta}$-estradiol. Enhanced expression of P450 1B1 promotes cancer cell proliferation and metastasis. There are at least 25 polymorphic variants of P450 1B1 and some of these have been reported to be associated with eye diseases. In addition, P450 1B1 polymorphisms can greatly affect the metabolic activation of many procarcinogenic compounds. It is necessary to understand the relationship between metabolic activation of such substances and P450 1B1 polymorphisms in order to develop rational strategies for the prevention of its toxic effect on human health.