• Journal of Environmental Science International
• /
• 제16권1호
• /
• pp.27-32
• /
• 2007

In this study, the concentrations of offensive odorous compounds seasonally emitted from the chemical plant at Chongju industrial complex in Korea were determined by the analytical methods of gas chromatography, high performance liquid chromatography and uv/vis spectroscopy. The kinds of offensive odorous compounds examined are formaldehyde, acetaldehyde, butyl aldehyde, propion aldehyde, n-valeric aldehyde, iso-valeric aldehyde, hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, trimethyl amine and ammonia. The seasonally emission levels of all odorous compounds except dimethyl sulfide at 13 sampling points of plant were lower than those of the regulation standard levels of the industrial complex in Korea. The levels were the highest in June, and lowest in December. The propion aldehyde and iso-valeric aldehyde in June and December, butyl aldehyde in December, and n-valeric aldehyde were not detected in all the three seasons at any sampling points of the plant examined. But in June, dimethyl sulfide was emitted up to 16 times than that of the regulation level.

• Bulletin of the Korean Chemical Society
• /
• 제15권10호
• /
• pp.873-881
• /
• 1994

The approximate rate and stoichiometry of the reaction of excess diisobutylaluminum hydride-dimethyl sulfide complex($DIBAH-SMe_2$) with organic compounds containing representative functional group under standardized conditions (toluene, $0{\circ}C$) were examined in order to define the reducing characterstics of the reagent and to compare the reducing power with DIBAH itself. In general, the reducing action of the complex is similar to that of DIBAH. However, the reducing power of the complex is weaker than that of DIBAH. All of the active hydrogen compounds including alcohols, amines, and thiols evolve hydrogen slowly. Aldehydes and ketones are reduced readily and quantitatively to give the corresponding alcohols. However, $DIBAH-SMe_2$ reduces carboxylic acids at a faster rate than DIBAH alone to the corresponding alcohols with a partial evolution of hydrogen. Similarly, acid chlorides, esters, and epoxides are readily reduced to the corresponding alcohols, but the reduction rate is much slower than that of DIBAH alone. Both primary aliphatic and aromatic amides examined evolve 1 equiv of hydrogen rapidly and are reduced slowly to the amines. Tertiary amides readily utilize 2 equiv of hydride for reduction. Nitriles consume 1 equiv of hydride rapidly but further hydride uptake is quite slow. Nitro compounds, azobenzene, and azoxybenzene are reduced moderately. Cyclohexanone oxime liberates ca. 0.8 equiv of hydrogen rapidly and is reduced to the N-hydroxylamine stage. Phenyl isocyanate is rapidly reduced to the imine stage, but further hydride uptake is quite sluggish. Pyridine reacts at a moderate rate with an uptake of one hydride in 48 h, while pyridine N-oxide reacts rapidly with consumption of 2 equiv of hydride for reduction in 6h. Similarly, disulfides and sulfoxide are readily reduced, whereas sulfide, sulfone, and sulfonic acid are inert to this reagent under these reaction conditions.

• Mass Spectrometry Letters
• /
• 제6권1호
• /
• pp.17-20
• /
• 2015

Sesamin, one of the lignans in sesame seed, was a labile compound in MS and it was reported that the protonated molecule of sesamin decomposed easily in ES ionization process and it cannot be detected (G. Yan, et al., Rapid Commun Mass Spectrom. 2007, 21, 3613-3620). To protect labile compounds, an amino-cyclodextrin (NCyD) was added to the sample to promote the host-guest interaction complex in ESI-MS. As a result, sesamin was ionized as the NCyD-sesamin-NCyD (1:2) complex without undesired decomposition, suggesting that the amino-CyDs assist the ionization of the labile molecules capped with CyDs by host-guest interaction and these compounds were ionized without their decomposition, those are like amino-CyD complex-assisted ionization. The amino-CyD complexes of sesamin and sesamolin were also analyzed by their ion-mobility MS.

• Journal of Korean Society of Water and Wastewater
• /
• 제27권2호
• /
• pp.165-175
• /
• 2013

This study aims to analysis correlation in septic tank and sewer pipe between odor substances and complex odor. For the analysis, convert odor substances to odor intensity, and estimate the effect of odor substances on complex odor. As a result, both Hydrogen sulfide and Methyl mercaptane of specified offensive odor substances accounted for 29 percent of the effect of odor substances on complex odor. Hydrogen sulfide and Methyl mercaptane are major cause of odor from septic tank and sewer pipe. The result of this study is suggested to be used as a preliminary data for research on analysis complex odor and odor substances.

• Korean Journal of Plant Resources
• /
• 제33권2호
• /
• pp.63-72
• /
• 2020

Fermented complex from garlic and nine medicinal plants were developed as a natural whitening material. Tyrosinase inhibition activity was determined and four active compounds were isolated. The nutritional components of fermented garlic complex (FGC) were analyzed to confirm the applicability as a functional food material. Tyrosinase inhibitory effect of FGC was 88.6%. Methanol extract was partitioned with EtOAc, n-BuOH and H₂O. From the EtOAc fraction (47 g), which showed the highest yield, active fractions were separated by repeated TLC, silica gel and ODS column chromatography to isolate active compounds. The chemical structures of the isolated compounds were analyzed by NMR and MS spectra. Phenylpropanoid compounds of 2,4,5-trihydroxy-benzenepropanoic acid (1) (1.9 mg) and 2,3,5-trihydroxy-benzenepropanoic acid (2) were confirmed. In addition, 2,4-dihydroxy-hydrocinnamic acid (3) (3.3 mg) and (+)sesamin (4) (6.1 mg) were isolated. These compounds will be useful as index compounds or functional compounds in FGC.

• Korean Journal of Environmental Agriculture
• /
• 제34권1호
• /
• pp.46-51
• /
• 2015

BACKGROUND: This study aimed at investigating the effects of sulfur-containing compounds widely used as environment-friendly organic fungicides against ginseng anthracnose, and determining the appropriate application concentration for lowering chemical injury to ginseng leaves. Ginseng anthracnose, caused by Colletotrichum gloeosporioides, is a destructive disease that significantly reduces the yield of ginseng. METHODS AND RESULTS: Ginseng anthracnose, caused by Colletotrichum gloeosporioides, is a destructive disease that significantly reduces the yield of ginseng. In a 2-year-old ginseng grown in a pot, treatment with loess-sulfur complex containing 0.06% sulfur and fermented loess-sulfur complex containing 0.13% sulfur did not show any chemical injuries. In order to measure the therapeutic effectiveness, various sulfur-containing compounds were applied to the plants after they were infected with ginseng anthracnose. Treatment with lime sulfur complex (400 dilution) showed the highest ginseng anthracnose control value, followed by fermented loess-sulfur complex (20 dilution), fermented loess-sulfur complex (40 dilution), and loess-sulfur complex (400 dilution) treatments. These compounds were applied before the outbreak of anthracnose disease in order to measure the preventive effectiveness, and in this case, treatment with fermented loess-sulfur complex (40 dilution) showed the highest control value and it was comparable to the value of the pesticide treatment used as the control in this experiment. CONCLUSION: Fermented loess-sulfur complex could be recommended as an environment-friendly organic material to control the occurrence of ginseng anthracnose.

• Journal of Environmental Health Sciences
• /
• 제39권5호
• /
• pp.418-425
• /
• 2013

Objective: This study was carried out for the purpose of identifying major substances contributing to the production of odor and evaluating the characteristic of odors. Methods: Complex odor and 17 odorous compounds were measured at 18 waste transfer stations located in Seoul. Results: The dilution ratio value of complex odor ranged from 4 to 30 times in the boundary layer of 18 waste transfer stations. At 6 measurement points among the 18 waste transfer stations, the dilution ratio values exceeded standards (15 times). When the results were evaluated in terms of their contribution to the formation of malodor, the patterns indicated that the highest concentration values in the residential waste disposal process were of i-valeraldehyde and acetaldehyde, while butyraldehyde and acetaldehyde accounted for a large proportion of odorous compounds from the waste recycling process. Conclusions: It was found that butyraldehyde and acetaldehyde were the primary compounds released from the food waste disposal process. Overall, aldehyde compounds were the greatest contributor to detectable odor intensity emitted at the waste transfer stations.

• Journal of Environmental Health Sciences
• /
• 제32권4호
• /
• pp.292-303
• /
• 2006

The Volatile Organic Compounds(VOCs) are emitted from various sources and have lots of different form. Recently human are spending the many times at indoor area and indoor air pollution is issued the important social problem. The emission sources of indoor air pollutants are very various, also indoor building materials are composed of very complex chemical compounds, these indoor building materials discharge very much VOCs and other hazardous compounds. In this study, we performed the small chamber test to investigate the VOCs emission concentration and characteristics involving five kinds of the indoor building materials(furniture material, wooden floor, wall paper, paint and tile) under different conditions of four temperature and relative humidity as account of the air flow rate(AFR), air exchange rate(AER), loading factor and air velocity respectively. As the result, It was showed that building materials are emitted the highest VOCs concentration at the beginning of experiment and furniture material is emitted the highest VOCs concentration. Most of the materials were affected by temperature, but paint and tile material were affected by humidity.

• Genomics & Informatics
• /
• 제14권2호
• /
• pp.53-61
• /
• 2016

Toxoplasma gondii is an intracellular Apicomplexan parasite and a causative agent of toxoplasmosis in human. It causes encephalitis, uveitis, chorioretinitis, and congenital infection. T. gondii invades the host cell by forming a moving junction (MJ) complex. This complex formation is initiated by intermolecular interactions between the two secretory parasitic proteins-namely, apical membrane antigen 1 (AMA1) and rhoptry neck protein 2 (RON2) and is critically essential for the host invasion process. By this study, we propose two potential leads, NSC95522 and NSC179676 that can efficiently target the AMA1 hydrophobic cleft, which is a hotspot for targeting MJ complex formation. The proposed leads are the result of an exhaustive conformational search-based virtual screen with multilevel precision scoring of the docking affinities. These two compounds surpassed all the precision levels of docking and also the stringent post docking and cumulative molecular dynamics evaluations. Moreover, the backbone flexibility of hotspot residues in the hydrophobic cleft, which has been previously reported to be essential for accommodative binding of RON2 to AMA1, was also highly perturbed by these compounds. Furthermore, binding free energy calculations of these two compounds also revealed a significant affinity to AMA1. Machine learning approaches also predicted these two compounds to possess more relevant activities. Hence, these two leads, NSC95522 and NSC179676, may prove to be potential inhibitors targeting AMA1-RON2 complex formation towards combating toxoplasmosis.

• Bulletin of the Korean Chemical Society
• /
• 제28권12호
• /
• pp.2162-2190
• /
• 2007

The newly-developed Meerwein-Ponndorf-Verley (MVP) type reagents using aluminum, boron and other metals for reduction of organic functional groups such as carbonyl and epoxy compounds have been surveyed. highlighted and reviewed in this account are the appearance of new MPV type reagents and their application to the selective reduction of organic functions. Finally, this account emphasizes the distinct contrast in the reducing characteristics existed between metal hydride reagents and MPV reagents, and compares their usefulness in organic synthesis.