• Journal of Microbiology and Biotechnology
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• v.28 no.5
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• pp.784-795
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• 2018

Bacillus amyloliquefaciens Pc3 was isolated from Antarctic seawater with antifungal activity. In order to investigate the metabolic regulation mechanism in the biosynthesis of lipopeptides in B. amyloliquefaciens Pc3, GC/MS-based metabolomics was used when exogenous indole was added. The intracellular metabolite profiles showed decreased asparagine, aspartic acid, glutamine, glutamic acid, threonine, valine, isoleucine, hexadecanoic acid, and octadecanoic acid in the indole-treated groups, which were involved in the biosynthesis of lipopeptides. B. amyloliquefaciens Pc3 exhibited a growth promotion, bacterial total protein increase, and lipopeptide biosynthesis inhibition upon the addition of indole. Besides this, real-time PCR analysis further revealed that the transcription of lipopeptide biosynthesis genes ituD, fenA, and srfA-A were downregulated by indole with 22.4-, 21.98-, and 26.0-fold, respectively. It therefore was speculated that as the metabolic flux of most of the amino acids and fatty acids were transferred to the synthesis of proteins and biomass, lipopeptide biosynthesis was weakened owing to the lack of precursor amino acids and fatty acids.

• 보존과학연구
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• s.27
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• pp.203-214
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• 2006

The work focuses on the chemical analysis of organic residues in archaeological soils. Particularly, the detection of manuring in archaeological soils can provide important information concerning early human behavior, diet, parasites, ecological adeptation. In this study, archaeological soils excavated at bunto-ri, Haenam and kumjang-ri, Kyungju were used to assess the possibility as indicators of ancient human activity in archaeological areas. The sampled soils were analyzed soil color, pH for their physical and chemical properties and GC/MSD to detect and quantify specific compound. The results showed that the sampled soils were normal pH(6.8~7.2) and soil color of light brown to yellowish brown. Also, the result from the GC/MS analysis indicated that their compounds were hexadecanoic acid, octadecanoic acid, nonadecane, docosanoic acid, methyl ester, teracosanoic acidand methyl este from bunto-ri site and 1-heptadecene, cyclotetracosane, tetracosane, cyclotetracosane,1-docosene, n-nonadecane, tetracosanoic acid methyl ester, cyclooctacosane, 1-nonadecene, eicosane, cyclotriacontane from kumjang-ri site. These compounds are not only normal soil materials but also animal lipid compounds. And the more scientific analysis of the soils will solve a curiosity for artificially incoming.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.316-323
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• 1996

Flavor components in mash of Takju prepared by different raw materials such as nonglutinous rice, glutinous rice, barley and wheat flour were detected by GC and GC-MS method using non-polar column. Seven alcohols, 15 esters, 10 organic acids, 1 aldehyde, 4 benzenes, 3 phenols, 8 alkans, 2 ketones and 5 others were found in takju after 16 day of fermentation. takju by wheat flour had the most various components of volatile flavor. Treatment with addition starter had less flavor component than that without addition starter in takju by nonglutinous rice. Nine kinds of flavor components including acetic acid ethyl ester, 3- methyl-1-butanol, acetic acid, ethyl benzene, acetic acid 3-methyl butyl ester, 2-phenylethanol, 2,6-di-tert-butyl-4-methyl phenol. plumbagic acid and 1,2-benzenedicarboxylic acid dibutyl ester were commonly detected in all the treatments. Especially, 2,4,0-trimethyl-1,3-benzenediamine was isolated in takju that was made of nonglutinous rice without addition starter. Diethyl sulfide, 4-methoxy benzaldehyde, docosane and 2-methyl propyl octadecanoic acid were isolated from takju by nonglutinous rice with addition starter. Propionic acid ethyl ester, acetic acid butyl ester, 2-methyl butane and 3-methyl pentane were isolated from takju glutinous rice. 2-Hydroxy-4-methyl pentanoic acid and 2-methyl tridecane were isolated from akju by barley 3-(Methylthio)-1-propanol. hexanoic acid ethyl ester, butanoic acid monomethyl ester, tridecanoic acid, ethyl tetramethyl cyclopentadiene and 1,5-diaza-2,9-diketocyclotetradecane were isolated from takju by wheat flour. Major volatile flavor components were acetic acid ethyl ester, 3-methyl-1-butanol, acetic acid and 2-phenylethanol.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.656-660
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• 2005

The relationship between the gas chromatographic (GC) patterns of sauce made of barley bran and ranked order in sensory analysis was investigated by multiple regression analysis (MRA). Most of the 42 barley bran sauce samples comprised about 34 peaks, in which the content of 9, 12-octadecanoic acid methyl ester was the highest, followed by those of 2-furanmethanol and 2-furancarboxaldehyde. It is difficult to estimate the aroma quality of barley bran sauce samples on the basis of only one peak. The 34 aroma compounds of the 42 samples were analyzed by an MRA model featuring six transformations. The most precise fit was calculated from the absolute value transformed with the root square of each peak, and the multiple determination coefficient showed that 91.6% of the variation in the sensory score could be explained on the basis of GC data.

• Applied Chemistry for Engineering
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• v.4 no.2
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• pp.381-392
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• 1993

Anionic oligomer surfactants, dodecyl polyoxyethylene ${\alpha}-sulfa$ alkanoates, had been synthesized through the esterification of dodecyl polyoxyethylene glycol and ${\alpha}-sulfa$ alkanoic acid with straight chain alkyl group having from 10 to 18 carbon atoms to good yield. ${\alpha}-sulfa$ alkanoic acids were obtained by reaction with long chain alkanoic acids and sulfur trioxide-dioxane complex, and dodecyl polyoxyethylene glycols, by addition reaction with dodecyl alcohol and ethylene oxide(addition, 5, 10, 20mol) respectively. All the synthetic products could be separated by means of the thin layer and column chromatography, and their structure has characterized with IR, $^1HNMR$ and elemental analysis, respectively.

• Journal of the Korean Society of Food Culture
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• v.12 no.2
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• pp.173-182
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• 1997

This study was carried out in order to investigate effective aroma components of Korean traditional soy sauce. Volatile aroma compounds were extracted by solvent extraction, TMS esterification of methyl acetate extracts and SDE, and analyzed by GC/MSD. 140 voltile aroma compounds were detected by three different extraction methods. Most abundant volatile compounds were acids and phenols and identified aldehydes, hydrocarbons, ketones, furans, furanone, alcohols, esters, nitrogen compounds, sulfur compounds and thiazoles, too. In the analytical sensory evaluation of soy sauce aroma, there were significant differences between each soy sauce sample in all test item. To sum up, Sweet odor was high in Kyupjang. Nutty odor and traditional soy sauce odor were similarly high in Kyupjang and high concentration soy sauce. Kyupjang had high score in overall odor preference than Chungiangs. The result of multiple regression of soy sauce odor characteristics and gas chromatography pattern demonstrated that offensive and sour odor was affected by octadecanoic acid. Contributive compounds to sweet odor were 1,2-benzenedicarboxylic acid and 3,6-dioxa-2,7-disilacotane. Benzoic acid 4-methyl ethyl ester and nonacotane were identified as major compounds of nutty odor. Contribu live variables of traditional soy sauce odor were benzoic acid 4-methyl ethyl ester and 9,12-octadecadienoic acid. The main factors of odor preference were 3-methyl pentanoic acid, acetic acid, 2,6-dimethyl heptadecane and 3,6-dioxa-2,7-disilacotane.

• Korean Journal of Weed Science
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• v.17 no.4
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• pp.375-381
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• 1997

When the rice straw mulched, the inhibition of weed growth was observed in the paddy field. If we use these allelopathic effect of decreased weed establishment, we can save labor, and protect environment. Aqueous extract of rice straw were bioassayed using water foxtail seeds to investigate chair effects on the germination and the growth, and to identify allelopathic compounds. The major results obtained were summarized as follows : Aqueous extract was fractioned by solvent, among various fractions, II-3, II-4 fractions inhibited the coleoptile and the radical of water foxtail, by 100%, respectively. There were fumaric acid and 4 unknown organic acids. Seven organic acids including fumaric acid inhibited the growth and germination of water foxtail in $10^{-2}$M solution. One of the most effective allelopathic compounds in rice straw was identified the unknown organic acid, as molecular weight 253, by GC/MS.

• CELLMED
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• v.2 no.2
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• pp.20.1-20.5
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• 2012

$Gynura$ $segetum$ (Lour.) Merr. ($Compositae$) is a well recognized medicinal plant in Indonesia and Malaysia. It is believed to have an anticoagulant effect and is used in treating snake-bites, inflammations and other skin afflictions. This study was carried out to evaluate the antimicrobial effects of $Gynura$ $segetum$ leaves extracts and its fractions. The chemical compositions of the active extracts were also determined. The antimicrobial activities of different solvent extracts of leaves of $Gynura$ $segetum$ were evaluated using the agar well-diffusion method. The Minimum Inhibitory Concentration (MIC) of the active subfractions was determined by the tube dilution method. Gas Chromatography-mass spectrometry (GC-MS) analysis was carried out to identify the chemical compositions of the active extracts. The ethyl acetate fraction and its subfraction E4 performed potent antimicrobial activities and fifteen known chemical constituents were identified by GCMS analysis as 4-vinylphenol, 1-tetradecene, phenol, 2,4-bis(1,1-dimethylethyl), 1-hexadecene, E-15-heptadecenal, hexadecanoic acid, 1,2-benzenedicarboxylic acid, dibutyl ester, 1-docosene, octadecanoic acid, 1-eicosene, cyclotetracosane, 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl)ester, butanedioic acid, monomethyl ester, niacin and 4-hydroxy-benzoic acid. The results of this study suggested a connection between the antimicrobial activities and the chemical structures. The plant may be used as a potential source for antimicrobial agents.

• Journal of Conservation Science
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• v.33 no.5
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• pp.345-354
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• 2017

A mural was discovered in the Ssanggyesa temple located in Jindo island, during repair of the Daeungjeon Hall. A study was conducted to determine the binding medium used for preparing the mural. Pyrolysis/GC/MS and IR spectrometry were used to analyze a painting specimen. Direct approach and on-line methylation approach were attempted for the pyrolysis/GC/MS. In IR analysis, the spectra of the specimen were found to be different from those of Asian lacquer, yellow lacquer, animal glue, and acrylic emulsion resin. They were also not identical to the standard IR spectra of drying oils such as linseed oil. Pyrolysis/GC/MS results of the specimen were different from those of Asian lacquer, yellow lacquer, animal glue, and acrylic emulsion resin. In the mean time, palmitic acid, octadecanoic acid, nonanedioic acid, and octadecenoic acid, which are characteristic pyrolysis products of dried drying oil, were detected. In addition, the pyrolysis/GC/MS chromatograms of the specimen and dried drying oil were also very similar. Therefore, it was concluded that the painting was prepared using drying oil as a binding medium.

• Microbiology and Biotechnology Letters
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• v.26 no.1
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• pp.7-14
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• 1998

To study the oxygen tolerance mechanism of bifidobacteria, we have studied the growth of cells, the activities of the enzymes which were related with oxygen, such as catalase, superoxide dismutase(SOD), NADH oxidase, and NADH peroxidase, and cellular fatty acid compositions of Bifidobacterium adolescentis and B. longum under anaerobic and aerated (microaerobic and aerobic) conditions. B. longum grew relatively well under the microaerobic conditions, whereas the growth of B. adolescentis was inhibited under the same aerated conditions. B. adolescentis had extremely low level of NADH oxidative enzymes while B. longum had the relatively high level of NADH oxidative enzymes, whose activities were dramatically increased from 3.7 to 11.4 times by microaerobic condition but not in B. adolescentis. The activity of SOD was unexpectedly high in B. adolescentis compared with in B. longum under anaerobic and aerated conditions. The activities of catalase were not detected in all samples tested in this study. We also found that normal $C_{l6:0}$ and $C_{18:1}$ were the major fatty acids in B. adolescentis and B. longum under anaerobic and aerated conditions. 2.2-14.1% $C_{l9:0}$ cyclo fatty acid was detected only in B. longum and the fatty acid was increased by the addition of the aeration. The $C_{l9:0}$ cyclic fatty acid was identified as a cis 9, 10-methylene octadecanoic acid, which was different from lactobacillic acid in the cyclized site. 6.6%-24.6% of dimethyl acetals (DMA) which came from plasmalogen were observed in the B. adolescentis and B. longum grown under anaerobic condition, and the components were notably decreased in the cells grown under the aerated conditions. It is believed that NADH oxidative enzymes play an important role to detoxify oxygen metabolites of Bifidobacteriurn spp. under anaerobic and microaerobic conditions. Independently from oxidative enzymes, it seems that oxygen stress may induce the change of the level of cellular fatty acids showing an increase of $C_{l9:0}$ cyclo in B. longum and a decrease of $C_{l8:1}$ of plasmalogen in B. longum and B. adolescentis to adapt in environment.