• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.1
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• pp.48-53
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• 2006

The asymmetric biosynthesis of ethyl (S)-4-chloro-3-hydrobutanoate from ethyl 4-chloro-3-oxobutanoate was investigated by using whole cells of Candida magnoliae JX120-3 without the addition of glucose dehydrogenase or $NADP^+/NADPH$. In a one-phase system, the bioconversion yield was seriously affected on the addition of 12.1 g/L ethyl 4-chloro-3-oxobutanoate. In order to reduce this substrate inhibition, a water/ n-butyl acetate two-phase system was developed, and the bioreduction conditions optimized with regard to the yield and product enantiometric excess value. The optimal conditions were as following: water to n-butyl acetate volume ratio of 1:1, 4.0 g DCW/L active cells, 50 g/L glucose and $35^{\circ}C$. By adopting a dropwise substrate feeding strategy, high concentration of ethyl 4-chloro-3-oxobutanoate (60 g/L) could be asymmetrically reduced to ethyl (S)-4-chloro-3-hydrobutanoate with high yield (93.8%) and high enantiometric excess value (92.7%).

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.638-643
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• 1998

The volatile flavor components in Takju made from mashed glutinous rice and barley rice were identified by GC and GC-MS using polar column. Twenty eight kinds of flavor compounds including 10 alcohols, 9 esters, 2 acids, 7 aldehydes were identified. At the beginning of fermentation 14 kinds of volatile components were detected and the kinds of volatile components were increased up to maximum after fermentation for 16 days. The contents of volatile components in the sample made from glutinous rice contained slightly higher than the sample made from barley rice. Ethyl alcohol, n-propyl alcohol, iso-amyl alcohol, n-hexyl alcohol, hexenyl alcohol, 2-phenylethyl alcohol, ethyl acetate, ethyl succinate, 2-phenylethyl acetate, butyic acid, benzaldehyde and 3-methoxybenzaldehyde were detected in the both of the sample throughout the fermentation process. Five kinds of aldehyde including ethyl propionate, iso-amyl acetate, ethyl caprylate and ethylphenyl acetate were detected only in the sample fermented for 16 days. The main components of the both sample were ethyl alcohol, iso-amyl alcohol, 2-phenylethyl alcohol, 2-phenylethyl acetate, hexenyl alcohol and iso-butyl alcohol. Besides ethyl acetate and benzaldehyde from glutinous rice Takju and hexenyl alcohol from barley rice Takju were found as main components.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.35-39
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• 2012

The purpose of this study was to research about the ingredients for anti-oxidation and anti-wrinkle effects of the solvent fractions from Agrimonia pilosa L. hot water (AW) and 70% ethanol (AE) extracts. The electron donating ability of the solvent fractions from AW and AE extracts showed 84.9, 92.5% in ethyl acetate layer of AW and AE at 1,000 ppm. The superoxide dismutase like activity of solvent fractions from AW and AE extracts showed 61.8% in ethyl acetate layer of AW extracts and 58.0% in buthanol layer of AE extracts at 1,000 ppm. For anti-wrinkle effect, elastase inhibition effect of the solvent fractions from AW and AE extracts showed 55.2, 70.1% in ethyl acetate layer of AW and AE extracts at 1,000 ppm. And collagenase inhibition effect of the solvent fractions from AW and AE extracts showed highest inhibition effect as 90.6% in ethyl acetate layer of AW extract and 88.6% in $n$-butyl alcohol layer of AE extract at 1,000 ppm. All these findings suggested that solvent fractions from AW and AE extracts has an anti-oxidation and anti-wrinkle effects.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1243-1249
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• 2006

Volatile flavor compounds in commercial crab-like flavorants were compared by mean of solid phase microextraction(SPME) and liquid continuous extraction (LLCE)/GC/MSD methods. A total of 86 volatile flavor compounds were detected. Of these, 71 were positively identified consisting mainly of sulfur-containing compounds (13), aldehydes (3), ketones (2), esters (26), alcohols (5), aromatic compounds (3), terpenes (8), acids (2) and miscellaneous compounds (9). SPME method was more effective than LLCE method in detection of volatile components in commercial crab-like flavorants. Eight S-, N-containing compounds such as dimethyl sulfide, dimethyl disulfide, dipropyl disulfide, 3-(methylthio)propyl acetate, 3-(methylthio) propanal, 3-(methylthio) propanol, 2-methyl-3-(methylthio) pyrazine and 2-methyl-5-(methylthio) pyrazine, 8 esters such as styrallyl acetate, ethyl acetate, isoamyl acetate, benzyl acetate, ethyl pentanoate, butyl pentanoate, isoamyl pentanoate and furfuryl acetate were considered as major components in crab-like flavorants.

• The Journal of the Korea Contents Association
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• v.6 no.12
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• pp.163-168
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• 2006

Hg-free fluorescent lamps were fabricated and electro-optical characterization were measured for using LCD backlight. PDP phosphors, nitro-cellulose and n-butyl acetate were mixed and coated uniformly in glass tube without stain. The glass tubes were sintered at $550^{\circ}C$ for 20 minutes, vacuumed to $10^{-6}$ torr and supplied discharge gas by using a gas mixture. After various experiment about phosphors thickness and inner diameter of glass tube, the appropriate phosphors thickness and inner diameter of glass tube were obtained. The luminance and luminous efficiency of manufactured fluorescent lamps with Ne+Xe discharge gas were $6,270cd/m^2$, 13 lm/W under 75 kHz sinusoidal wave voltage, respectively.

• KSBB Journal
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• v.29 no.2
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• pp.124-130
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• 2014

Acer tegmentosum was a traditional Korean herbal medicine showing various pharmacological activities. In this work, A. tegmentosum were extracted with boiling water and then successively partitioned with dichloromethane, ethyl acetate, n-butyl alcohol (n-BuOH), and water. Salidoside, the target compound, was purified in n-BuOH phase using a chromatography method. For the analysis of salidoside, TLC and LC-MS were used as well as on-line screening $HPLC-ABTS^+$ assay with three different wavelength of 254, 280, and 320 nm. An amount of 1.34 g of salidoside were obtained in n-BuOH phase fromAcer tegmentosum was a traditional Korean herbal medicine showing various pharmacological activities. In this work, A. tegmentosum were extracted with boiling water and then successively partitioned with dichloromethane, ethyl acetate, n-butyl alcohol (n-BuOH), and water. Salidoside, the target compound, was purified in n-BuOH phase using a chromatography method. For the analysis of salidoside, TLC and LC-MS were used as well as online screening $HPLC-ABTS^+$ assay with three different wavelength of 254, 280, and 320 nm. An amount of 1.34 g of salidoside were obtained in n-BuOH phase from 3 kg of dry biomass. The on-line screening $HPLC-ABTS^+$ assay is rapid and efficient tool to search bioactivity from A. tegmentosum. 3 kg of dry biomass. The on-line screening $HPLC-ABTS^+$ assay is rapid and efficient tool to search bioactivity from A. tegmentosum.

• Safety and Health at Work
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• v.2 no.1
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• pp.39-51
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• 2011

Objectives: This study was designed to evaluate exposure levels of various chemicals used in wafer fabrication product lines in the semiconductor industry where work-related leukemia has occurred. Methods: The research focused on 9 representative wafer fabrication bays among a total of 25 bays in a semiconductor product line. We monitored the chemical substances categorized as human carcinogens with respect to leukemia as well as harmful chemicals used in the bays and substances with hematologic and reproductive toxicities to evaluate the overall health effect for semiconductor industry workers. With respect to monitoring, active and passive sampling techniques were introduced. Eight-hour long-term and 15-minute short-term sampling was conducted for the area as well as on personal samples. Results: The results of the measurements for each substance showed that benzene, toluene, xylene, n-butyl acetate, 2-methoxy-ethanol, 2-heptanone, ethylene glycol, sulfuric acid, and phosphoric acid were non-detectable (ND) in all samples. Arsine was either "ND" or it existed only in trace form in the bay air. The maximum exposure concentration of fluorides was approximately 0.17% of the Korea occupational exposure limits, with hydrofluoric acid at about 0.2%, hydrochloric acid 0.06%, nitric acid 0.05%, isopropyl alcohol 0.4%, and phosphine at about 2%. The maximum exposure concentration of propylene glycol monomethyl ether acetate (PGMEA) was 0.0870 ppm, representing only 0.1% or less than the American Industrial Hygiene Association recommended standard (100 ppm). Conclusion: Benzene, a known human carcinogen for leukemia, and arsine, a hematologic toxin, were not detected in wafer fabrication sites in this study. Among reproductive toxic substances, n-butyl acetate was not detected, but fluorides and PGMEA existed in small amounts in the air. This investigation was focused on the air-borne chemical concentrations only in regular working conditions. Unconditional exposures during spills and/or maintenance tasks and by-product chemicals were not included. Supplementary studies might be required.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.1
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• pp.105-114
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• 1998

In this study, 108 thinners were analyzed to identify their composition. The purposes of this study were to provide the data for MSDS and worker exposure levels. Thinners were collected from manufacturing industries, distributors and users. Wide ranges of thinner components were found ; Toluene, xylene, and ethyl benzene were most often found. Next, MIBK, cellosolve acetate, butyl cellosolve, and butyl acetate were found in 20-40 thinners. Others, such as acetone, n-hexane, cyclohexane, heptane, methylcyciohexane, octane and nonane were also found. There were about 5-6 components in each thinner. In the view point of Industrial Hygiene, Benzene was the most important component of thinners, which procures leukemia. Benzene was found from 8 kinds of thinners out of the total 108 surveyed. Thus, Content of benzene in thinners must be evaluated when industrial hygiene surveys are performed. Aromatic hydrocarbons were identified from 71 kinds of thinners out of total 108 and their contents were 10-87%. Alkanes were not contained in automobile painting, spraying, degreasing, urethane and epoxy thinners but lacquer, enamel and coating thinners.

• Food Science and Preservation
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• v.11 no.1
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• pp.63-70
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• 2004

The antimicrobial substances from Rhodiola sachalinensis were extncted, isolated and identified. The highest level of antimicrobial activity and its yield were obtained in methanol extract. The minimum inhibition concentrations of the methanol extract were 500 $\mu\textrm{g}$mL on agar plate and 100 $\mu\textrm{g}$mL in broth media for four gram positive and four gram negative microbials. The methanol extract was fractionated by n-hexane, chloroform, ethyl ether, ethyl acetate, and butanol, orderly. The separate was developed on the TLC plate with different solvent system ratio of chloroform and methanol. Nine substances were isolated from chloroform and methanol mixture(9:1, v/v). Among them, three isolates showed antimicrobial activity. Three substances separated by HPLC were identified by GC/MS(EI) spectrum and $^1$H, /sup13/C-NMR spectrum. They were gallic acid, (-)-epicatechin and kaempferol. The antimicrobial activities of each substances were shown gallic acid, (-)-epicatechin, kaempferol orderly.

• Journal of Life Science
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• v.24 no.1
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• pp.26-38
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• 2014

To examine the antioxidant activities of 11n selected miscellaneous cereal grains (proso millet, yellow glutinous proso millet, hwanggeumchal sorghum, glutinous sorghum, white glutinous sorghum, yellow glutinous foxtail millet, nonglutinous foxtail millet, green glutinous foxtail millet, golden foxtail millet, barnyard millet, and adlay), the free radical-scavenging activities of 80% ethanol extracts of the individual grains were investigated using 1,1-diphenyl-2-picryl-hydrazl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods. The ethanol extracts of hwanggeumchal sorghum, glutinous sorghum, and barnyard millet grains exhibited more potent free radical-scavenging activities as compared to the other grains. When these three ethanol extracts were sequentially fractionated with n-hexane, methylene chloride, ethyl acetate, and n-butanol, the majority of the antioxidant activities were detected in the ethyl acetate and butanol fractions in which phenolic ingredients were abundant. The ethyl acetate and butanol fractions of hwanggeumchal sorghum and the ethyl acetate fraction of glutinous sorghum showed higher antioxidant activity than that of ${\alpha}$-tocopherol. Both ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods demonstrated that these organic solvent fractions could inhibit lipid peroxidation. The ethyl acetate fractions from hwanggeumchal sorghum, glutinous sorghum, and barnyard millet grains could suppress tertiary-butyl hydroperoxide (TBHP)-induced apoptotic events, including sub-G1 peaks, ${\Delta}{\Psi}m$ loss, activation of caspase-9 and caspase-3, and cleavage of PARP and lamin B, in human HL-60 cells. These results show that the grains of hwanggeumchal sorghum (Sorghum bicolor L. Moench cv. Hwanggeumchalsusu), glutinous sorghum (Sorghum bicolor L. Moench cv. Chalsusu), and barnyard millet (Echinochloa esculenta) possess efficient antioxidant activity, which could protect cells from oxidative stress-mediated cytotoxicity.