• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.366-371
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• 2007

The volatile components in Eoyuk-jang, a traditional Korean fermented food, were isolated using solvent extraction, and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 36 components, including 11 aliphatic hydrocarbons, 4 acids, 2 ketones, 5 phenols, 7 alcohols, 1 pyrazines, 4 pyrones and furanones, and 2 miscellaneous components, were found in Eoyuk-jang; among them, butanoic acid was quantitatively dominant. In addition, the aroma-active compounds were determined by gas chromatography-olfactometry (GC-O) using aroma extract dilution analysis (AEDA). A total of 20 aroma-active compounds were detected by GC-O. Butanoic acid (rancid) and methional (cooked potato-like) were the most potent aroma-active compounds with the highest FD factors $(Log_3$, FD), followed by 2-methyl-2-butanol (soysauce-like), 3-hydroxy-2-butanone (buttery), and 2-furanmethanol (burnt sugar-like).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.56-62
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• 2014

This study aims to investigate the applicability of supercritical fluid extraction as a dewaxing technique to restore the beeswax-treated volume of the Annals of the Joseon Dynasty in various deterioration and damage conditions. Thus, this study analyzed the dewaxing efficiency and changes in physical and morphological properties before and after dewaxing, by applying the optimal supercritical fluid extraction dewaxing condition ($70^{\circ}C$, 40 MPa, $CO_2$, Co-solvent 20% DCM, 2 hour) to 3 kinds of beeswax-treated paper with different deterioration rates (dry artificial aging of 10, 20 and 30 days at $120^{\circ}C$). After dry artificial aging at $120^{\circ}C$ for 30 days, the average molecular weight of the beeswax-treated specimen was $1.856{\times}10^5g/mol$, showing deterioration about 80% of the beeswax-treated paper before dewaxing. It was a similar level to the molecular weight of the bees-waxed volume of the Annals of the Joseon Dynasty that has a higher degree of damage. As a result of analyzing the dewaxing efficiency through FT-IR analysis, this study discovered that it was possible to effectively dewax beeswax-treated paper in the range of deterioration 20 to 80% with this supercritical fluid extraction dewaxing technique applied. As a result of analyzing changes in the physical and morphological properties before and after dewaxing, the viscosity tended to decrease to a slight degree, and since no morphological deformation or damage of stencil fibers was found, it was concluded possible to conduct stable dewaxing through this supercritical fluid extraction technique.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.497-502
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• 2008

The volatile components in Gamdongchotmoo kimchi, unfermented and fermented for 3 or 25 days, were extracted via solvent-assisted flavor evaporation (SAFE), and then analyzed via gas chromatography/mass spectrometry (GCMS). A total of 57 components, including 14 S-containing compounds, 22 terpene hydrocarbons, 13 aliphatic hydrocarbons, 4 alcohols, and 4 miscellaneous components, were detected in Gamdongchotmoo kimchi. Among them, the S-compounds were quantitatively dominant. The aroma-active compounds were also determined via gas chromatography-olfactometry (GC-O), using aroma extract dilution analysis (AEDA). A total of 16 aroma-active compounds were detected via GC-O. The most intense aroma-active compounds in Gamdongchotmoo kimchi included 4-isothiocyanato-1-butene ($Log_3$ FD factor 7, rancid), an unknown($Log_3$ FD factor 7, spicy) and another unknown ($Log_3$ FD factor 7, seasoning-like). In addition, other aroma-active compounds, including dimethyldisulfide ($Log_3$ FD factor 6, rotten onion-like/sulfury), 2-vinyl-[4H]-1,3-dithiin ($Log_3$ FD factor 5, spicy/garlic-like), and an unknown ($Log_3$ FD factor 5, rancid/cheese-like) might be crucial to the flavor characteristics of Gamdongchotmoo kimchi.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.516-521
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• 2008

This study was conducted to optimize the analysis condition and quantify the 2-acetyl-1-pyrroline (2AP) in the brown aroma rice. Extraction effect of the solvent for 2AP was the order of ethanol>acetonitrile>methanol in the range from 30 to $90^{\circ}C$. In the extraction time of 15, 30, 60, and 90 min, the 30 min had the highest 2AP concentration, and it was decreased according to lapse of time. At grinding time, 5 sec resulted in highest 2AP concentration. It was recommended that five sec grinding time, using ethanol, at $90^{\circ}C$ for 30 min was the optimization conditions to quantify the 2AP. Hyangmibyeo2ho and Aranghyangchalbyeo were mild aroma. In the foreign aroma rice, 11 of 19 accessions of Indica types and 2 of 6 accessions of Japonica types were more than mild aroma. Finally, 30 accessions of aroma rice were selected based on their 2AP concentration and agronomic traits.

• Analytical Science and Technology
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• v.18 no.3
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• pp.201-205
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• 2005

Tri-octyl amine (TOA) is used in solvent extraction process for radioactive waste. This compound may be degraded to di-octyl amine (DOA), mono-octyl amine (MOA) by radioactive materials. Amount of TOA, DOA and MOA in TOA must be monitored because they production of these compounds means degradation of which leads to a decrease in the extraction yield. Retention behavior for TOA, DOA and MOA are studied with Phenomenex LUNA-$C_{18}$ ($4.6mm{\times}25cm$) analytical column and $CH_3OH:H_2O$ (50 mmol $CH_3COONH_4$) eluent by liquid chromatography. Optimum condition for these compounds is $CH_3OH:H_2O$ (50 mmol $CH_3COONH_4$) = 85 : 15 ratio. TOA, DOA and MOA compounds is well separated within 20 minute. Dynamic range is $30{\sim}160{\mu}g/mL$ for TOA, $5{\sim}100{\mu}g/mL$ for DOA and $0.1{\sim}5{\mu}g/mL$ for MOA, respectively. The detection limit are $0.1{\mu}g/mL$ for TOA, $1{\mu}g/mL$ for DOA (in SCAN mode) and $0.1{\mu}g/mL$ for MOA (in SIM mode) in this system with $20{\mu}L$ sample loop.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.532-537
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• 2014

Cortex Phellodendri (CP) is derived from the dried bark of Phellodendron amurense. It has been widely used as a drug in traditional Korea medicine for treating diarrhea, jaundice, swelling pains in the knees and feet, urinary tract infections, and infections of the body surface. Many analytical methods have been used to study oriental herbal medicines, such as thin-layer chromatography, column liquid chromatography, and high performance liquid chromatography (HPLC). In this study, preparative centrifugal partition chromatography (CPC) was successfully carried out in order to separate pure compounds from a CP methanol extract. The optimum two-phase CPC solvent system was composed of n-butanol: acetic acid: water (4:1:5 v/v/v). The flow rate of the mobile phase was 3 mL/min in ascending mode with rotation at 1,000 rpm. The CPC-separated fraction and purification procedures were carried out by preparatory HPLC. The $^1H$ NMR spectrum revealed that the resonances at ${\delta}$ 4.10 and 4.20 ppm corresponded to three protons ($-OCH_3$), whereas those at ${\delta}$ 6.10 ppm corresponded to two protons ($-OCH_2O-$). Further, two aromatic protons (H-11 and H-12) conveys a doublet-doublet pattern. The H-11 doublet and H-12 doublet appear at ${\delta}$ 7.98 and 8.11, respectively. The $^{13}C$ NMR. spectrum showed a tetrasubstituted with a methylenedioxy group at C2 and C3, and two methoxy groups at C9 and C10. The chemical structure of the berberine was identified by $^1H$, $^{13}C$-nuclear magnetic resonance and electrospray ionization-mass spectroscopy spectral data analysis.

• Korean journal of food and cookery science
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• v.16 no.3
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• pp.221-225
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• 2000

This study was conducted to investigate the usefulness of Perilla frutescens var. acuta as a natural spice. Volatile flavor components of dried Perilla frutescens var. acuta were extracted by supercritical fluid extraction method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Identification of volatile flavor components was based on the RI of GC and mass spectrum of GC-MS. A total of 24 components, including 4 hydrocarbons, 3 aldehydes, 8 alcohols, 4 esters, 3 acids and 2 miscellaneous components were identified in the essential oils. L-Perillaldehyde was found to be the major volatile flavor component of dried Perilla frutescens var. acuta. The masking effects of Perilla frutescens var. acuta on meaty and fishy flavor were measured by sensory evaluation. Meaty flavor was significantly reduced with the addition of 0.05%, 0.1%, and 0.2% Perilla frutescens var. acuta. The addition of 0.1% and 0.2% powdered Perilla frutescens var. acuta also reduced the fishy flavor of mackerel.

• Korean journal of food and cookery science
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• v.16 no.3
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• pp.216-220
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• 2000

Volatile flavor components in the fruits of dried Zanthoxylum schinifolium were extracted by supercritical fluid extraction method using diethyl ether as solvent. Essential oils were analyzed by gas chromatography (GC) and combined gas chromatography-mass spectrometry (GC-MS). Identification of volatile flavor components was based on the RI of GC and mass spectrum of GC-MS. A total of 30 components, including 6 hydrocarbons, 4 aldehydes, 8 alcohols, 5 esters, 4 acids and 3 miscellaneous components were identified in the essential oils. Geranyl acetate, ${\beta}$-phellandrene, D-limonene and citronellal were found to be major volatile flavor components in fruits of dried Zanthoxylum schinifolium. The masking effects of Zanthoxylum schinifolium on meaty and fishy flavor were measured by sensory evaluation to investigate the usefulness of Zanthoxylum schinifolium as a natural spice. Meaty flavor was significantly reduced with the addition of 0.05% and 0.1% Zanthoxylum schinifolium. And the addition of 0.l% powdered Zanthoxylum schinifolium also reduced the fishy flavor of mackerel.

• Applied Chemistry for Engineering
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• v.28 no.5
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• pp.597-600
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• 2017

$(C_{10}H_8N_2H)_2Cr_2O_7$ was synthesized by reacting 4,4'-bipyridine and chromium (VI) trioxide. The structure of the product was characterized with FT-IR (infrared spectroscopy) and elemental analysis. The oxidation of benzyl alcohol using $(C_{10}H_8N_2H)_2Cr_2O_7$ in various solvents showed that the reactivity increased with the increase of the solvent dielectric constant, in the order of DMF (N,N'-dimethylformamide) > acetone > chloroform > cyclohexane. In the presence of DMF, an acidic catalyst such as $H_2SO_4$ $(C_{10}H_8N_2H)_2Cr_2O_7$ oxidized benzyl alcohol (H) and its derivatives ($p-OCH_3$, $m-CH_3$, $m-OCH_3$, m-Cl, $m-NO_2$). Electron donating substituents accelerated the reaction rate, whereas electron acceptor groups retarded the reaction rate. Hammett reaction constant (${\rho}$) was -0.70 (308 K). The observed experimental data were used to rationalize the hydride ion transfer in the rate determining step.

• Korean Journal of Medicinal Crop Science
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• v.16 no.6
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• pp.446-454
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• 2008

An advanced extraction method by ultrasonic extraction with applied solid phase extraction (SPE) has been developed for the determination of simultaneous eight major ginsenosides, namely ginsenosides Rg1, Re, Rf, Rb1, Rg2, Rc, Rb2, and Rd in the root of Panax ginseng. Four extraction methods including n-BuOH reflux extraction (Method A), 70% EtOH reflux extraction (Method B), 50% MeOH reflux extraction with SPE (Method C), and 50% MeOH ultrasonication with SPE clean-up process (Method D) were investigated for the determination of eight major ginsenosides. Total contents of ginsenosides were highest by extraction of Method C as $2.408{\pm}0.011%$. However, Method D was evaluated as relatively simpler and more efficient method due to short extraction time, small solvent consumption and less expensive, compared to conservative reflux method. Ginsenosides were also satisfactorily separated with good resolution and the accuracy range was between 1.05 and 4.06% as relative standard deviation (RSD) by Method D. SPE condition and HPLC condition were further optimized for determination of eight major ginsenosides by the ultrasonic extraction method. Conclusively, ultrasonic extraction of 2 g sample of ginseng using ultrasonic bath and 1 loading for SPE was evaluated as proper condition for extraction of ginseng.