• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1691-1695
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• 2016

The objective of this study was to determine the antioxidant activities of rice bran extracts by three different extraction methods. Rice bran was extracted by solvent extraction, saponification extraction, and supercritical fluid extraction. The antioxidant activities of the rice bran extracts were determined based on ABTS and DPPH radical scavenging activities, reducing power, and lipid peroxidation inhibitory activity. The unsaponifiable matter (USM) extracted by the saponification method showed higher ABTS (671.7 mg Trolox equivalent antioxidant capacity (TEAC)/g) and DPPH (330.7 mg TEAC/g) radical scavenging activities as well as reducing power ($A_{700}=1.14$) than those of the solvent extract (ME) and supercritical fluid extract (SFE). Inhibitory effect on lipid peroxidation was higher in USM (68.7%) and SFE (75.4%) compared to ME (47.8%). USM indicated relatively higher antioxidant activities compared with those of SFE and ME. These results show that the saponification method for extraction of USM from rice bran extracted was the most effective method for enhancement of antioxidant activity. In addition, these extracts from rice bran could be used as functional ingredients in the food industry.

• KSBB Journal
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• v.20 no.3
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• pp.205-209
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• 2005

Studies for the commercial production of sesame oil using th supercriticl carbon dioxide were made. Characteristics of sesame oil containing one of natural antioxidant 'sesamol', which only exist at sesame seed were also studied during the supercritical fluid extraction. Among the various factors influencing the sesamol contents in the sesame oil, the roasting time and temperature were checked, because sesamol can be converted from sesamol in through pyrolysis. We found that the sesamol content was increased rapidly under the condition of roasting temperature over $200^{\circ}C$ with longer roasting time. The sesamol content was increased as the temperature and pressure increased, which was caused by increase of solubility of sesamol against sesamol oil. And the sesamol content was increased also with lower speed of supercritical fluid, which increased the contact time with the raw material. The sesamol content was also increased using water increase up to $1\%$ as the entrainer. When the extraction performance with the supercritical fluid was compared to the conventional compressed extraction, the sesamol content was increased up to 11.5 times with the entrainer.

• KSBB Journal
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• v.20 no.3
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• pp.210-214
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• 2005

The characteristics of sesame oil containing one of natural antioxidant, ' $\gamma$-tocopherol', were studied with the supercritical $CO_2$ extraction. Although $\gamma$-tocopherol has a lower vitamin E value in biological systems than $\alpha$-tocopherol, it is a more potent antioxidant with in oils. For the research of various factors influence to the $\gamma$-tocopherol contents increment, we have checked roasting time and temperature, as well as pressure, temperature and flow rate of supercritical fluid. As a result, we found that the $\gamma$-tocopherol content was maintained constant under the condition of roasting temperature over $200^{\circ}C$. With the longer roasting time, $\gamma$-tocopherol content was increased. Except 250 bar, the $\gamma$-tocopherol content was maintained constant under the condition of the various pressure of supercritical fluid. But $\gamma$-tocopherol content was increased with lower flow rate of supercritical fluid from 1 $m{\ell}$/L to 3 $m{\ell}$/L. When the extraction performance with the supercritical fluid was compared to the conventional compressed extraction, $\gamma$-tocopherol content was increased up to 1.6 times.

• The KSFM Journal of Fluid Machinery
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• v.12 no.4
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• pp.54-62
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• 2009

The feedwater heaters are Critical components in a nuclear power plant. As the operation years of heaters go by, the maintenance costs required for continuous operation increase. When the carbon steel components in nuclear make contact with running fluid, the wall thinning caused by FAC (flow accelerated corrosion) can be generated. Local wall thinning is inevitable at the area around wet steam entrance to be attacked due to the long term operation. Sometimes the shell with thinned wall is eventually ruptured. To identify the relationship between the local wall thinning and fluid behavior of the feedwater heater, the practical data of a plant, which were based on ultrasonic thickness measurement tests, were analyzed and CFD(Computed Fluid Dynamics) analyses were performed.

• Preventive Nutrition and Food Science
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• v.13 no.1
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• pp.12-17
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• 2008

Douchi, a popular seasoning agent in Chinese dishes prepared by the Aspergillus oryzae fermentation of black beans, was subjected to supercritical fluid extraction (SFE) and gas chromatography-mass spectrometry analysis for its volatile components. A total of 73 components were identified in two commercial brands, which were positively confirmed and quantified. Among the common components in the two brands were 18 acids, 12 alcohols, 11 aldehydes, 9 esters, 1 furan, 11 other oxygen-containing compounds, 4 pyrazines, 2 pyridines and 5 miscellaneous compounds. The most abundant components found were acetic acid, benzoic acid, 2,6-dimethylpyrazine, 2-piperidinone, 3-methylbutanoic acid, maltol, 4-ethylphenol, 2-methylpropanoic acid, butanoic acid, 2-pyrrolidinone, all fatty acids and some esters.

• KSBB Journal
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• v.29 no.6
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• pp.405-413
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• 2014

In this study, gemcitabine (Gem)-Poly(L-lactic acid) (PLLA) conjugates were synthesized through an amide linkage reaction. Then, the microparticles of Gem-PLLA/PLLA blends containing gemcitabine were prepared using a supercritical fluid process, called aerosol solvent extraction system (ASES). Gemcitabine-loaded Gem-PLLA/PLLA microparticles obtained from the ASES process showed a spherical shape. The amount of gemcitabine released after 30 day incubation in a phosphate buffer solution of pH 7.4 was about 90% of the total amount of gemcitabine present in the product.

• The KSFM Journal of Fluid Machinery
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• v.15 no.5
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• pp.20-26
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• 2012

An APU(Auxiliary Power Unit) for helicopters has been developed in Korea and tested at the AETF(altitude engine test facility) in KARI(Korea Aerospace Research Institute) for the purpose of the military qualification. A cell correlation test was performed before the official test, and the results are within the tolerance. The APU has the capability of supplying electric power as well as compressed air to the helicopters. It was tested at bleed extraction conditions, electric power extraction conditions, and maximum continuous concurrent power conditions within the entire helicopter flight envelop. Some special test equipments were implemented for the measurement of air flowrate, electric power and so on. The tests were successfully performed and their results satisfy the requirements of the helicopters.

• Journal of Pharmaceutical Investigation
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• v.16 no.2
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• pp.76-84
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• 1986

Berberine is one of alkaloids extracted from Phellodendri Cortex or Coptidis Rhizoma and has extensively used as an antibacterial and antidiarrheal drug. In order to increase the bioavailability of berberine preparation, berberine pamoate was synthesized and investigated on its usage in vitro and in vivo. Berberine was more rapidly extracted from herbal plants by hot water extraction method than soxhlet extraction method. Berberine pamoate was easily synthesized from berberine hydrochloride and potassium pamoate solution and identified using the infrared spectrum. Quantitative analysis of berberine was possible in methanol solution by fluorometric determination. The dissolution rate of berberine pamoate was more decreased than that of berberine hydrochloride in simulated gastric fluid and simulated intestinal fluid. The remaining proportion of berberine pamoate in the small intestine of rat was maintained at high concentration for a long time as compared with that of berberine hydrochloride.

• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.178-186
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• 2021

The wave power extraction by multiple Wave Energy Converters (WECs) deployed in a Y-shaped Water Channel Resonator (WCR) has been investigated. A WCR consists of a long water channel, and a V-shaped wave guider installed at the entrance of a water channel. If the period of the incident waves coincides with the natural periods of the fluid in a WCR, resonance occurs, as a result, the internal fluid in a WCR is greatly amplified. To estimate the wave power by multiple WECs placed at the antinodal points in a WCR, the heave motion response, time-averaged power, and capture width ratio were calculated for several design parameters. Also, the systematic model tests were conducted in a 2D wave tank. The numerical results are in good agreement with the experimental data. It was verified that a WCR helps the WECs to produce electricity more effectively by amplifying the wave energy in a WCR.

• Korean Journal of Acupuncture
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• v.37 no.2
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• pp.88-96
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• 2020

Objectives : The purpose of this study was to investigate the anti-oxidant and anti-aging effect of the seed of Euphorbia lathyris L. extracted by supercritical CO₂. Methods : Human dermal fibroblast cells dosed with the extract from Euphorbia lathyris L. were harvested and the intracellular proteome was analyzed to examine the expression of proteins related collagen synthesis pathway, metalloproteinases (MMPs), extracellular matrix (ECM)-cell interaction, cytokines, and antioxidant enzymes by 2-dimensional gel electrophoresis. Results : Fatty acid analysis of the extract from Euphorbia lathyris L. showed oleic acid was 84% and linoleic acid was 4.1%. Antioxidative effect was about 53% by beta carotene bleaching assay. In 2-dimensional polyacrylamide gel electrophoresis (2-D PAGE) analysis, fifteen protein changes in five mechanisms which were collagen synthesis pathway, MMPs, ECM-cell interaction, cytokines, and antioxidant enzymes were analyzed. Conclusions : This study suggests the supercritical extraction from the seed of Euphorbia lathyris L. could be used as anti-oxidant substances for pharmacopuncture.