• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1281-1287
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• 1997

This study was conducted to investigate the antimutagenic effects of methyl alcohol extracts from Auricularia auricula and Gyrophora esculenta on the SOS response induced by 4-nitroquinoline-1-oxide (4NQO), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), mitomycin C (MMC) and 3-amino-1,4- dimethyl-5H-pyrido-[4,3-b]indol (Trp-P-1) in E. coli PQ37/plasmid pKM101. In the mutagenic test on test strain, both methyl alcohol extracts did not show mutagenic activity. In the antimutagenic test, each sample strongly inhibited the mutagenecity induced by 4NQO, MNNG, MMC and Trp-P-1. Methyl alcohol extracts from Auricularia auricula and Gyrophora esculenta showed inhibitory effects of 52% and 59% against 4NQO, 49% and 58% against MNNG, 53% and 64% against MMC, and 61% and 64% against Trp-P-1, respectively. Gyrophora esculenta extracts on the antimutagenicity showed relatively higher inhibitory effects than that of Auricularia auricula.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.593-599
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• 2007

In this study, we examined the volatile flavor components in the mashes of takju prepared using different yeasts such as Saccharomyces coreanus, S. ellipsoideus, S. carlsbergensis, S. cerevisiae (Baker's yeast), and S, rouxii by GC and GC-MS. Fourteen alcohols, 13 esters, 5 acids, 3 aldehydes, 7 amines, and 2 other compounds were identified in the mash after 6 days of fermentation. On day 6, the takju fermented by S. coreanus had the greatest variety of volatile flavor components. Fifteen flavor components, including ethanol, isobutyl alcohol, isoamyl alcohol, methyl pentanol, 1,3-butanediol, 3-methylthio-1-propanol, benzeneethanol, ethyl lactate, acetic acid, acetaldehyde, and 1,3-cyclohexane diamine, were typically detected in all the treatments. The relative peak areas of the volatile components were as follows: alcohols (96.758-99.387%), esters (0.081-0.968%), acids (0.040-0.640%), aldehydes (0.266-0.959%), and amines (0.011-0.047%). In particular, 1-propanol, isobutyl alcohol, 3-methyl-1-butanol, 2,3-butanediol, trimethyl benzylalcohol, heptene-2,4-diol, ethyl lactate, diethyl succinate, ethyl nonanoate, methyl hexadecanoate, linoleic acid, hexadecanoic acid, and acetaldehyde were hish in the takju made by S. coreanus. Also, ethyl stearate was high in the takju made by S. carlsbergensis, and hexanoic acid was high in the takju made by S. cerevisiae. Finally, methyl pentanol, 1,3-butanediol, 3-methylthio-1-propanol, benzene ethanol, ethyl octadecanoate, acetic acid, pentanal, and 1,3-cyclohexane diamine were high in the takju made by S. rouxii.

• Bulletin of the Korean Chemical Society
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• v.19 no.11
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• pp.1233-1238
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• 1998

Transglycosylation reactions among methyl 2,3,4,6-tetra-O-methyl-D-glycopyranosides and isomeric butyl alcohols or cyclohexanol took place in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) in dichloromethane. The extent of the reaction after 1 h and 24 h from mixing was determined by gas chromatography (GC). Anomerization of the substrate took place during the course of transglycosylation, which favors α anomer regardless of the anomeric configurations of the starting glycosides. Transglycosylation also favors the a anomer regardless of the steric bulkiness of the alcohol. tert-Butyl alcohol did not give any transglycosylation, suggesting the steric hindrance of approaching the bulky alcohol to the oxonium intermediate. A mechanism for the transglycosylation have been proposed.

• Bulletin of the Korean Chemical Society
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• v.27 no.12
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• pp.2040-2044
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• 2006

Dielectric studies of methyl acrylate with 1-propanol, 1-butanol, 1-heptanol and 1-octanol binary mixtures have been carried out over the frequency range from 10 MHz to 10 GHz at temperatures of 283, 293, 303 and 313 K using Time Domain Reflectometry (TDR) for various concentrations. The Kirkwood correlation factor and excess inverse relaxation time were determined and discussed to yield information on the molecular structure and dynamics of the mixture. The values of the static dielectric constant, relaxation time and the Kirkwood correlation factor decrease with increased concentration of methyl acrylate in alcohol. The Bruggman plot shows a non-linearity of the curves for all the systems studied indicates the heterointeraction which may be due to hydrogen bonding of the OH group of alcohol with C=O of the methyl acrylate. The excess inverse relaxation time values are negative for all the systems at all the temperatures indicates that the solute-solvent interaction hinders the rotation of the dipoles of the system.

• Journal of Powder Materials
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• v.13 no.4 s.57
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• pp.263-268
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• 2006

In this study, the colloidal stability and sedimentation behavior of crystalline $TiO_2$ particles (300nm) in various organic solvents have been investigated by means of a backscattered light flux profile (Turbiscan). The backscattered light flux profiles revealed that the $TiO_2$ nanoparticles were readily sedimented in water, methyl alcohol, and ethyl alcohol due to a flocculation-induced particle growth, while a particle coalescence and a sedimentation of the $TiO_2$ nanoparticles were hardly observed in isopropyl alcohol. The migration velocities of the $TiO_2$ particle were measured as around 6.15/min, 12.53 m/min, 6.51m/min, and 0.18m/min for water, methyl alcohol, ethyl alcohol, and isopropyl alcohol, respectively, showing a remarkably slow migration of the $TiO_2$ particles in isopropyl alcohol.

• Analytical Science and Technology
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• v.7 no.3
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• pp.321-327
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• 1994

The mild thermal decomposition of 7, 7-dimethyl-1, 2, 3, 4, 5-pentaphenyl-7-silanorbornadiene with excess methyl alcohol proceeds to give 1-methoxydimethylsilyl-1, 2, 3, 4, 6-pentaphenylcyclohexa-2, 5-diene which is colorless needle crystal. The cophotolysis of the solution of 7-silanorbornadiene in the excess ethyl alcohol proceeds with loss of silylenes to give ethoxydimethylsilane which is insertion reaction product of silylene with O-H bond of ethyl alcohol. According to above results, it is presumed that the mechanism of photochemical decomposition and that of mild thermochemical decomposition of 7-silanorbornadiene are different.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.449-455
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• 2011

This study was performed to develop antimicrobial films using polyvinyl alcohol and methyl cellulose. Methyl cellulose and polyvinyl alcohol films plasticized with PEG(polyethylene glycol) were prepared by solvent casting process under addition of 0.025~1.0 wt% ampicillin and 0.1~1.0 wt% streptomycin as an antimicrobial agent. The mechanical properties of prepared films were examined by universal testing machine(UTM). Tensile strength of methyl cellulose films was 15.44~21.70 $N/mm^2$. Tensile strength of PVA(15 wt%) film was 20.2~51.5 $N/mm^2$, and the tensile strength of the antimicrobial films were decreased linearly with increasing the antibiotic loading amount up to 1 wt%. Antimicrobial activities of PVA and methyl cellulose films containing ampicillin and streptomycin through the disc diffusion test for the Staphylococcus aureus and Escherichia coli. The antimicrobial activity of methyl cellulose films and PVA containing ampicillin were higher than that of containing streptomycin methyl cellulose films. The results indicate the films may be a proper materials for antimicrobial packing applications.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1144-1150
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• 1997

Volatile flavor components of soybean koji kochujang made from a glutinuous rice by improved method were analyzed by using a purge and trap method during fermentation, and identified with GC-MSD. Fifty-six volatile flavor components including 16 alcohols, 15 esters, 7 acids, 4 aldehydes, 5 alkanes, 3 ketones, 1 benzene, 1 alkene, 2 phenol and 2 others were found in improved kochujang. The number of volatile flavor components detected immediately after making kochujang were 32 and increased to 46 components after 30 day of fermentation. The most number 55 of volatile flavor components were found after 90 day of fermentation. Thirty-one kinds of volatile flavor components were commonly found through the fermentation period 9 alcohols such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 8 esters such as methyl acetate, ethyl acetate, 2-methylpropyl acetate, 3 aldehydes such as butanal, acetaldehyde, furfural and 11 othesrs. Although the various types of peak areas (%) of volatile flavor components were shown in kochujang during the fermentation days, ethanol. ethyl acetate, ethyl butanoate, 2-methylpropyl acetate, 2-methyl-1-propanol and 3-methyl-1-butanol were mainly detected during fermentation. Those might be the major volatile flavor components in kochujang made by improved method. Peak area of ethanol was the highest one among the volatile flavor components at immediately after mashing and 90 day while ethyl acetate showed the highest Peak area after $30{\sim}60$ day of fermentation and 3-methyl-1-butanol showed the highest peak area after $120{\sim}150$ day of fermentation.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.286-292
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• 2007

Free amino acids and volatile compounds of fresh garlic and its liqueur were investigated to search elution profile of those components as basic data for development of garlic liqueur. The garlic was soaked in 20% alcohol solution and then sampled every week for 5 weeks. The major free amino acids were L-aspartic acid, L-glutamic acid, L-arginine, L-alanine, L-proline, L-asparagine and L-serine. Neutral amino acids such as L-threonine, L-proline, L-valine and L-leucine, and aromatic amino acids such as tyrosine and phenylalanine were eluted over 80% of those content in fresh garlic after 3 weeks of soaking, but acidic, basic and sulfur containing amino acids were below 80% even after 5 weeks. Sulfide compounds such as diallyl trisulfide, diallyl disulfide, methyl allyl disulfide, 2-vinyl-4H-1,3-dithi in, 3-vinyl-3,4-dihydro-1,2-dithiin, 3,5-diethyl-1,24-trithiolane, isobutyl isothiocyanate and diallyl sulfide were identified as major volatile compounds of fresh garlic by using GC/MS. Among volatile compounds of fresh garlic, allyl alcohol, diallyl disulfide, 3,5-diethyl-1,2,4-trithiolane, diallyl trisulfide and 3,4-dimethoxy furan were eluted to liqueur, but those compounds except 3,5-diethyl-1,2,4-trithiolane were lowered in liqueur during soaking. Furfural, 5-methylfurfural, 5-hydroxymethylfurfural, dimethyl pyrazine, furfuryl alcohol, 3-hydroxy-2-bytanone and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyr-an-4-one were generated newly and their content increased in liqueur during soaking.

• Korean Journal of Pharmacognosy
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• v.38 no.4
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• pp.403-408
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• 2007

xBrassicoraphanus is an intergenic breed crossed between Brassica campetris L. ssp. pekinensis and Raphanus sativus L. that have been daily consumed. xBrassicoraphanus was known to have good tastes and biological activities. Nevertheless, its constituetnts were not elucidated yet. Thus, in the present study, to indirectly evaluate the biological activity of xBrassicoraphanus, 12 compounds were isolated from leaves and roots of xBrassicoraphanus. On the basis of spectroscopic evidences, the structures of these compounds isolated from leaves of xBrassicoraphanus. were identified as ${\beta}-sitosterol$, indole-3-acetonitrile, ferulic acid, methyl ferulate, linolenic acid methyl ester, linolenic acid and coniferyl alcohol, while the chemical structures of compounds isolated from the roots of were xBrassicoraphanus were characterized as ${\beta}-sitosterol$, indole-3-acetonitrile, ferulic acid, methyl ferulate, linolenic acid methyl ester, 1-methoxyindole-3-acetonitrile, goitrin, 4-hydroxycinnamyl alcohol, coniferyl alcohol, palmitic acid and daucosterol. These can be classified as three steroids, two indole cyanides, two cinnamic acid derivatives, one cinnamyl alcohol derivative, three fatty acid derivatives one isothiocyanate. These results suggest that the compounds isolated from xBrassicoraphanus were almost identical with known components of Brassica campetris L. ssp pekinensis or Raphanus sativus L. However, it is necessary to investigate more about the difference of amounts of constituents according to harvest time and variant species amounts.