• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.1-8
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• 2000

Fifty-seven extracts from flower, leaf and stem of Agastache rugosa O. Kuntze were prepared by varing extraction conditions: solvents (hot water, ethanol and NaCl solution); temp.$(60,\;80\;and\;100^{\circ}C)$ and solvent ratios (10 to 35 times per material). Lipid content of leaf was 9.54% and protein content of the flower where the essential amino acids were most abundant among all parts was 16.8%. Among six minerals (Na. Ca, Fe, P, K and Mg) detected from all parts of the plant, the content of K was the highest. Extraction yield rated higher in odor of water, ethanol and NaCl solution, respectively and the extractions reached eqilibrium in about 15 to 20 min, regardless of extraction conditions. pH values of all extracted solvents maintained neutral upon extraction and a few free sugars in forms of glucose and fructose were detected from ethanol extracts. Colors and organoleptic characteristics of the extracts which determine the properties of final products varied with extraction conditions.

• Journal of Life Science
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• v.21 no.1
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• pp.56-61
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• 2011

This study was performed to investigate effective extract conditions in fronds of the Ostrich fern (Matteuccia struthiopteris) to increase antioxidant compound contents and antioxidant capacity. Powder (1 g) of lyophilizated fronds were mixed with 3 kinds of solvents (MeOH, 80% EtOH and water). Extractions were carried out using not only immersion (room temp.), heating ($60^{\circ}C$) and stirring (200rpm) for 6 hr, but also through sonication in a 42 kHz ultrasonic bath for 15, 30 and 45 min. Extracts were filtrated and measured for contents of soluble solids (SS), total polyphenols (TP; tannic acid as a standard) and total flavonoids (TF; Naringin as a standard). Antioxidant activity was expressed as $RC_{50}$ for DPPH and ABTS radical scavenging. SS (0.317 $g{\cdot}g^{-1}$ db), TP (70.90 $mg{\cdot}g^{-1}$ db) and TF (41.53 $mg{\cdot}g^{-1}$ db) contents reached their highest levels when 30 minute sonication extraction with 80% EtOH was performed, and the highest DPPH and ABTS scavenging activity was observed in the same extraction conditions ($RC_{50}$=0.14 $mg{\cdot}ml^{-1}$ and 0.09 $mg{\cdot}ml^{-1}$, respectively). From the present investigation, it can be concluded that fronds of the ostrich fern can be used as a natural material for antioxidants, and sonication for 15-30 min with 80% EtOH is an ideal extraction method for increasing their antioxidant effects and saving extraction time.

• Journal of Life Science
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• v.23 no.12
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• pp.1495-1500
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• 2013

The objective of this study was to evaluate the anti-melanogenic effects of Hizikia fusiforme (HF) fractions in ${\alpha}$-melanocyte stimulating hormone-induced B16F10 mouse melanoma cells. Ethanol extractions of Hizikia fusiforme (EEHF) were subjected to fraction by using dichloromethane (CFHF), ethyl acetate (EAFHF), butanol (BFHF), and water (WFHF). EEHF, CFHF, and EAFHF inhibited tyrosinase activity and melanin synthesis in B16F10 mouse melanoma cells in a dose-dependent manner. The melanin contents were inhibited by 40.5% and 33.2% in response to treatment with 50 ${\mu}g/ml$ of EEHF and CFHF, respectively. In addition, tyrosinase activities showed a 53.3% and 54.1% reduction in treatment with 50 ${\mu}g/ml$ of EEHF and CFHF. Western blotting analysis showed that EEHF, CFHF, and EAFHF inhibited tyrosinase, TRP-1, TRP-2, and MITF expression in a dose-dependent manner. In conclusion, these findings indicate that ethanol and dichloromethane fractions of Hizikia fusiforme, which inhibit melanin synthesis and tyrosinase activity, are effective skin-whitening agents.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.66-72
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• 2018

Corn stover is known as a good candidate for a functional food ingredient when the main lignocellulosic material, lignin, is used as bioactive materials as form of polyphenolic compounds. The purpose of this study was to determine the microwave extraction conditions under which total phenolic compounds (TPC) and flavonoid contents of corn stover were maximized. Microwave-assisted extracts using sulfuric acid ranging from 0 to 1.0 mol with extraction time between 40 and 240 sec were conducted by using response surface methodology (RSM). Microwave power showed significant effects (p<0.05) and the concentrations of TPC and flavonoids increased with increased level of microwave power and extraction time. The optimum conditions for corn stover extraction were determined as 698.6 W, 240 sec, and 0 mol sulfuric acid, and the predicted value of TPC and flavonoid is 82.4 mg GAE/g DM and 18.1 mg/g DM, respectively. Microwave extraction was evaluated as an economic process with low energy consumption, short extraction and high extraction yield of bioactive including TPC and flavonoids compared to conventional extractions.

• Journal of Microbiology and Biotechnology
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• v.27 no.9
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• pp.1593-1601
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• 2017

Vibrio species are generally recognized as pathogens predominant in seafood along coastal areas. The food industry has sought to develop efficient microbial detection methods. Owing to the limits of conventional methods, this study aimed to establish a rapid identification method for Vibrio isolated from Korea, based on matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Four different preparation procedures were compared to determine the appropriate means to pretreat Vibrio species, using 17 isolates and five reference strains. Extended direct transfer and full formic acid extraction methods using bacterial colonies on agar plates revealed very low identification rates. Formic acid and trifluoroacetic acid (TFA) extractions using bacterial broth cultures were also performed. All Vibrio isolates and reference strains prepared by TFA extraction were successfully identified to the species level (17/22, 77.3%) and to the genus level (5/22, 22.7%). Thus, TFA extraction was considered the most appropriate method to pretreat Vibrio species for MALDI-TOF MS. The remaining 33 isolates and two reference strains were prepared by TFA extraction and analyzed by MALDI-TOF MS. Overall, 50 isolates were identified to the species level (40/50, 80%) and to the genus level (10/50, 20%). All isolates were identified as 43 V. alginolyticus, six V. parahaemolyticus, and one V. vulnificus species. V. alginolyticus and V. parahaemolyticus were isolated from fish offal (87.5% and 12.5%, respectively), seawater (91.3%, 8.7%), and shellfish (62.5%, 37.5%), whereas V. alginolyticus and V. vulnificus were isolated from sediment (90.9% and 9.1%, respectively). This study established a reliable system of MALDI-TOF MS preparation and analysis for Vibrio identification.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1244-1250
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• 2000

A method for simultaneous quantitative determination of plasticizers such as diethyl phthalate(DEP), di-n-propyl phthalate(DprP), di-n-butyl phthalate(DBP), di-n-pentyl phthalate(DPP), butylbenzyl phthalate(BBP), di-(2-ethylhexyl) phthalate(DEHP), dicyclohexyl phthalate(DCHP) and di-(2-ethylhexyl) adipate(DEHA), which are suspected as endocrine disruptors, in food was studied. A analysis method was optimized for the quantification of plasticizers in Jjambbong, which is a kind of fatty noodle, by using GC/FID. The detection limits of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 3.5, 5.3, 2.2, 2.2, 7.2, 1.7, 1.9 and 3.0 mg/kg, respectively. Much higher recovery was obtained by extraction with acetone/n-hexane(1:1) rather than hexane solvent system. The recovery of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 72.7, 85.9, 91.4, 97.1, 100.8, 103.2, 104.3 and 95.8% after 4 time extractions, respectively. The migration of plasticizers from PVC wraps into PVC wrap covered Jjambbong was conducted after shaking(120 rpm) for 30min at room temperature with chosen solvent system. It was found that the migration level of DEHA were 577, 706, 770 mg/kg into Jjambbong, respectively, while the other plasticizers were not observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.882-887
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• 2015

This study evaluated the nutritional compositions of dropwort (Oenanthe javanica) extracts depending on the ethanol concentrations. Extractions were performed with hot water, 50% ethanol, 80% ethanol, and 95% ethanol for 4 hours. Changes in yield, as well as total carbohydrate, crude protein, crude fat, total dietary fiber, free sugar, and mineral (Na, Fe, and Ca) contents were investigated. The highest extraction yield of ethanol extracts was 44.67% in 50% ethanol extract of dropwort. Crude protein content reached a maximum of 6.70% while carbohydrate content was highest at 19.6%, in 50% ethanol extract of dropwort. Crude fat content irregularly increased according to ethanol concentration as compared with hot water extract. Total dietary fiber content decreased in ethanol extract, but these changes were not concentration-related. Total sugar contents were highest in hot water and 80% ethanol extracts. Vitamin A content of ethanol extract was higher than that of hot water extract. Mineral (Na, Ca, and Fe) contents were significantly reduced in ethanol extract according to concentration of ethanol, whereas mineral contents were higher in ethanol extract than in hot water extract. Based on this study, ethanol extract of dropwort is more efficient for development of desirable processed foods.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.4
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• pp.37-45
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• 2015

In modern electronic warfare systems, a demand on the more accurate estimation method based on TDOA and FDOA has been increased. TDOA/FDOA localization consists of two-stage procedures: the extraction of information from signals and the estimation of emitter location. Various algorithms based on CAF(complex ambiguity function), which is known as a basic method, has been presented in the area of extractions. When we extract TDOA and FDOA information using a conventional method based on the CAF algorithm from communication signals, considerably long integration time is required for the accurate position estimation of an unknown emitter far from sensors more than 300 km. Such long integration time yields huge amount of transmission data from sensors to a central processing unit, resulting in heavy computiational complexity. Therefore, we theoretically analyze the integration time for TDOA/FDOA information using CRLB and propose a two-stage global optimization algorithm which can minimize the transmission time and a computational complexity. The proposed method is compared with the conventional CAF-based algorithms in terms of a computational complexity and the CRLB to verify the estimation performance.

• Nuclear Engineering and Technology
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• v.26 no.4
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• pp.461-470
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• 1994

Sorption experiments of $^{60}$ Co, $^{85}$ Sr. and $^{137}$ Cs onto sandstone particles in a batch were carried out to investigate the migration mobility. Sorption kinetics and reversibility as well as sorption mechanisms were examined. Sorption reaction occurred mostly within 10 hours on the outer surface of the sandstone particle but diffusion into the inner surface of the mineral has still occurred after that time. In order to distinguish sorption types of radionuclides, a sequential chemical extraction was introduced. The sorbed radionuclides were then extracted by applying different solutions of synthetic groundwater, CaCl$_2$, KCl and KOX-HA Especially KCl is adopted to extract the ion-exchanged cesium. Sorption types considered are reversible sorption under groundwater condition, ion exchange, association with ferro-manganese oxides or oxyhydroxides, and irreversible fixation. Strontium sorbs onto the sandstone surface mainly by fast and reversible ion exchange reaction. However, cobalt and cesium do not sorb by simple process. The main sorptive binding of cobalt was the association with ferro-manganese oxides and the secondary one was irreversible fixation. Diffusion into the lattice of minerals controlled the sorption rate of cobalt The main sorptin type of cesium was irreversible fixation, while ion exchange reaction was the secondary importance. Hence the oreder of migration mobility for the three radionuclides was Sr$^{2＋}$ ＞ Co$^{2＋}$ ＞ Cs$^{＋}$ in the sandstones.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.16 no.1
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• pp.77-93
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• 2003

This experimental study was performed to investigate the antifungal effects of mixture of Sophorac Subprostratae Radix, Aconti Radix, and Hibisci Syriaci Cortex by the three types of extraction in the dermatophytes such as Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum. The following results were obtained by using Minimum Inhibition Concentration(MIC) and Inhibition Zone. 1. MIC on Trichophyton mentagrophytes in Sample S-2, Sample S-3, and Sample-Y were 10${\mu}l$, respectively, showing the highest antifungal effect. 2. MIC on Epidermophyton floccosum in Sample S-2, Sample S-3, and Sample-Y were 10㎕ respectively, showing the highest antifungal effect. 3. MIC on Trichophyton rubrum in Sample S-3, Sample-Y were 10${\mu}l$ respectively, showing the highest antifungal effect. 4. The size of inhibition zone on Trichophyton mentagrophytes for Sample S-3 were 22.3mm in 10${\mu}l$, showing the highest antifungal effect. 5. The size of inhibition zone on Epidermophyton floccosum for Sample S-3 was 34.3mm in 10${\mu}l$, showing the highest antifungal effect. 6. The size of inhibition zone on Trichophyton rubrum for Sample-Y was 26.5mm in 10${\mu}l$, showing the highest antifungal effect. Whereas. in extractions, that of Sample S-3 was 12.5mm in 10${\mu}l$, showing the highest antifungal effect. 7. From the above results, Sample S-3 on Trichophyton mentagrophytes, Epidermophyton floccosum and Sample-Y on Trichophyton rubrum showed the highest antifungal effects. This results suggests that vinegar extraction excels other extraction method using water or ethanol to measure the antifungal effect on dermatophytes. In addition, the result shows that the extract of herbal medicines can be used to tinea pedis and if further study is performed, the use of the extract of herbal medicines will be valuable and beneficial in the clinical medicines. [NOTE] · S-S2 : 12-13w/v$\%$ Vinegar extract of mixture of Sophorae Subprostratae Radix, Aconti Radix, and Hibisci Syriaci Cortex. · S-S3 : 18-19w/v$\%$ Vinegar extract of mixture of Sophorae Subprostratae Radix, Aconti Radix, and Hibisci Syriaci Cortex. · S-Y : Miconazole nitrate