• Korean Circulation Journal
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• v.48 no.12
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• pp.1157-1159
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• 2018

• Journal of the Korean Applied Science and Technology
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• v.38 no.1
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• pp.118-125
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• 2021

In this study Orostachys japonica A. Berger used is a medicinal herb that has long been used as a folk remedy for cancer treatment. In this study, the antioxidant efficacy of the ethyl acetate fraction of Orostachys japonica A. Berger was confirmed. The results of the Orostachys japonica A. Berge ethyl acetate fraction of antioxidant activity assays showed Antioxidant effect of Orostachys japonica A. Berger EtOAc fraction extract at 0.10 mg/mL was showed a DPPH radical scavenging rate of 78.54% and ABTS+ radical scavenging rate of 73.48%. Also, the toxicity result of Orostachys japonica A. Berger EtOAc fraction extracts using alternative experimental animal model zebrafish, confirmed a 100% the survival of the zebrafish embryo was shown that there was no coagulation and no hatching delay at all concentrations. also ROS generation induced by UV-B irradiation was confirmed that the fluorescence intensity decreased as a whole in all larvae treated with Orostachys japonica A. Berger EtOAc fraction extracts. In particular, it was confirmed that ROS generation was effectively suppressed by showing a 35.7% reduction rate compared to the positive control at a concentration of 3 ㎍/mL. These results were confirmed that Orostachys japonica A. Berger EtOAc fraction extracts has the possibility of application in the cosmetics field as a natural antioxidant.

• Polymer(Korea)
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• v.38 no.3
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• pp.272-277
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• 2014

We studied in-line monitoring the dispersion of highly energetic material simulant by a twin screw extruder having a high temperature ultrasonic system. The simulant suspension system consisted of ethylene vinyl acetate and Dechlorane plus 25 as binder and filler, respectively. With increasing filling fraction, the ultrasonic velocity was not changed but the attenuation linearly decreased. It was possible to estimate the solid fraction of well dispersed suspension system by measuring ultrasonic attenuation. The ultrasonic attenuation of samples filled over 60 v% approached straight line with increasing filling fraction when the samples was extruded repeatedly. It was due to the enhanced dispersion of solid particles in the suspension system. It was believed that the degree of dispersion and filling fraction could be obtained by combination of on-line measurement like ultrasonic attenuation and off-line analysis like TGA and SEM with image analyzer.

• Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.168-173
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• 2011

The purpose of this study was to obtain a fraction with high antioxidative activity from second rockfish gelatin hydrolysates (SRSGHs), which were hydrolyzed with Alcalase and Flavourzyme through ultrafiltration membranes with serial digestions for 1 and 2 h, respectively, and to investigate the feasibility of this fraction as a potential functional food ingredient. Among various fractions that were ultrafiltered from the SRSGH with four types of membrane (1, 5, 10, and 30 kDa), the SRSGH-III fraction, which permeated the 10 kDa membrane but not the 5 kDa membrane, showed the highest antioxidant activity (protection factor=5.13) and angiotensin-I-converting enzyme-inhibiting activity ($IC_{50}$=0.82 mg/mL). These results suggest that the SRSGH-III fraction from the SRSGH can be used as a functional food ingredient. However, further studies examining its antioxidant activity in vivo as well as the different antioxidant mechanisms are needed.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.135-135
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• 1999

It is well known that Raman spectroscopy is powerful tool in analysis of sp3/sp3 bonding fraction in diamond-like carbon(DLC) films. Raman spectra of DLC film is composed of D-peak centered at 1350cm-1 and G-peak centered at 1530cm-1. The sp3/sp3 fraction is qualitatively acquired by deconvolution method. However, in case of DLC film, it is generally observed that G-peak position shifts toward low wavenumber as th sp3 fraction increases. However, opposite results were frequently observed in ta-C films. ta-C film has much higher residual compressive stress due to its high sp3 fraction compared to the DLC films deposited by CVD method. Effect of residual stress on G-peak position is most recommendable parameter in Raman analysis of ta-C, due to its smallest fitting error among many parameters acquired by peak deconvolution of symmetric spectra. In current study, the effect of residual stress on Raman spectra was quantitatively evaluated by free-hang method. ta-C films of different residual stress were deposited on Si-wafer by modifying DC-bias voltage during deposition. The variation of the G-peak position along the etching depth were observed in the free-hangs of 20~30${\mu}{\textrm}{m}$ etching depth. Mathematical result based on Airy stress function, was compared with experimental results. The more reliable analysis excluding stress-induced shift was possible by elimination of the Raman shift due to residual compressiove stress.

• Korean Journal of Pharmacognosy
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• v.35 no.3 s.138
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• pp.239-243
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• 2004

The ameliorating effect of the MeOH extract of the root of Platycodon grandiflorum on the ethanol-induced cognitive dysfunction in mice was investigated. The total MeOH extract was devided into two fractions, saponin rich fraction and non-saponin fraction. The mice with repeated administration of the total MeOH extract and those with saponin rich fraction both showed a markedly prolongεd latency time upon the step-through test (passive avoidance performance) performed after acute ethanol intoxication, while those with non-saponin rich fraction did not. The results suggest that the extracts from the root of Platycodon grandiflorum exert a beneficial effect on ethanol-induced memory impairment in mice and also suggest that these effects of the extracts might be ascribed to the saponin constituents.

• Journal of Microbiology and Biotechnology
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• v.24 no.7
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• pp.969-978
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• 2014

The aprE2 gene with its prosequence from Bacillus subtilis CH3-5 was overexpressed in Escherichia coli BL21(DE3) by using plasmid pET26b(+). After IPTG induction, active and mature AprE2 was produced when cells were grown at $20^{\circ}C$, whereas inactive and insoluble enzyme was produced in a large amount when cells were grown at $37^{\circ}C$. The insoluble fraction was resuspended with 6 M guanidine-HCl and dialyzed against 2 M Tris-HCl (pH 7.0) or 0.5 M sodium acetate (pH 7.0) buffer. Then active AprE2 was regenerated and purified by a Ni-NTA column. Purified AprE2 from the soluble fraction had a specific activity of $1,069.4{\pm}42.4U/mg$ protein, higher than that from the renatured insoluble fraction. However, more active AprE2 was obtained by renaturation of the insoluble fraction. AprE2 was most stable at pH 7 and $40^{\circ}C$, respectively. The fibrinolytic activity of AprE2 was inhibited by PMSF, but not by EDTA and metal ions. AprE2 degraded $A{\alpha}$ and $B{\beta}$ chains of fibrinogen quickly, but not the ${\gamma}$-chain. AprE2 exhibited the highest specificity for N-succinyl-Ala-Ala-Pro-Phe-pNA. The $K_m$ and $k_{cat}/K_m$ of AprE2 was 0.56 mM and $3.10{\times}10^4S^{-1}M^{-1}$, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1732-1739
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• 2016

The general components and cyclitol compounds of ice plant (Mesembryanthemum crystallinum) were analyzed to examine the possibility of using extracts as functional food materials, the antioxidant effects and antidiabetic activities of the extracts by solvent fraction were tested. Among the mineral contents, contents of K and Na were the largest ($1,213.33{\pm}2.52$ and $545.53{\pm}12.01mg/100g$, respectively), followed by S, Ca, P, and Mg in order of precedence. Among cyclitol compounds, content of D-pinitol was the largest ($4.04{\pm}0.08mg/g$) while contents of chiro-inositol and myo-inositol were relatively small ($2.82{\pm}0.01$ and $0.25{\pm}0.01mg/g$, respectively). Among total phenol contents by solvent fraction, contents of chloroform and ethyl acetate fractions were large ($35.80{\pm}1.33$ and $23.70{\pm}0.62mg\;GAE/g$, respectively). Among antioxidant activity levels examined by DPPH, ABTS, FRAP, and lipid/MA assays, the chloroform fraction commonly showed the highest level of activity while the ethyl acetate fraction showed relatively high levels of activity. The antioxidant activity levels were proportional to total phenol contents by solvent fraction. As for antidiabetic effects, all solvent fractions showed at least 50% ${\alpha}-glucosidase$ inhibitory activity levels while the ethyl acetate, butanol, and chloroform fractions showed high levels activity of $90.33{\pm}0.40$, $87.98{\pm}0.16$, and $86.38{\pm}0.51%$, respectively. The ${\alpha}-amylase$ inhibitory actively levels were in the range of $25.63{\pm}1.45{\sim}60.34{\pm}2.67%$, which was lower than the ${\alpha}-glucosidase$ inhibitory activity levels, but the inhibitory activity levels by solvent fraction were similar. Given the above study results, ice plant can be utilized as a natural material with antioxidative and antidiabetic functionality.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1672-1678
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• 2009

We studied the effects of aged total petroleum hydrocarbons (aged TPH) on the survival of allochthonous diesel-degrading Rhodococcus sp. strain YS-7 in both laboratory and field investigations. The aged TPH extracted from a crude-oil-contaminated site were fractionized by thin-layer chromatography/flame ionization detection (TLC/FID). The three fractions identified were saturated aliphatic (SA), aromatic hydrocarbon (AH), and asphaltene-resin (AR). The ratio and composition of the separated fractions in the aged TPH were quite different from the crude-oil fractions. In the aged TPH, the SA and AH fractions were reduced and the AR fraction was dramatically increased compared with crude oil. The SA and AH fractions (2 mg/l each) of the aged TPH inhibited the growth of strain YS-7. Unexpectedly, the AR fraction had no effect on the survival of strain YS-7. However, crude oil (1,000 mg/l) did not inhibit the growth of strain YS-7. When strain YS-7 was inoculated into an aged crude-oil-contaminated field and its presence was monitored by fluorescent in situ hybridization (FISH), we discovered that it had disappeared on 36 days after the inoculation. For the first time, this study has demonstrated that the SA and AH fractions in aged TPH are more toxic to an allochthonous diesel-degrading strain than the AR fraction.

• Journal of the Korean School Mathematics Society
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• v.18 no.4
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• pp.353-370
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• 2015

This study was conducted as a qualitative case study that explored how gifted 3rd-grade elementary school children who had learned the primary concepts of division and fraction, when they studied contents about decimal, formed the transformed primary concept and transformed schema of decimal by the learning of accurate primary concepts and connecting the concepts. That is, this study investigated how the subjects attained relational understanding of decimal based on the primary concepts of division and fraction, and how they formed a transformed primary concept based on the primary concept of decimal and carried out vertical mathematizing. According to the findings of this study, transformed primary concepts formed through the learning of accurate primary concepts, and schemas and transformed schemas built through the connection of the concepts played as crucial factors for the children's relational understanding of decimal and their vertical mathematizing.