• Applied Biological Chemistry
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• v.30 no.1
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• pp.88-94
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• 1987

To investigate ginseng oligopeptides with biological activities, the water extract was purified by ultra-filtration, gel filtration, ion-exchange and thin layer chromatography. Ultra-filtered water extract exhibited antilipolytic activity, inhibiting epinephrine-induced lipolysis in the isolated fat cells of rat epididymal adipose tissue. The filtrate was separated into 3 fractions by Sephadex G-25 gel filtration. Peptides were found only in the first fraction(S-FI). Saponine and sugars were also detected in tie fraction. S-FI fraction resolved further into 6 fractions by Dowex 50 ion-exchange chromatography. The sugar and saponine depleted fraction(P-F2) from the second chromatography showed antilipolytic activity. The P-F2 fraction revealed 6 spots on TLC. The 6 spots were isolated by TLC and identified as peptides.

• Journal of the Korean Society of Safety
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• v.19 no.4 s.68
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• pp.31-35
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• 2004

The A17075/CFRP multi-layered hybrid laminate material consists of the alternating A17075-T6 sheets and carbon/epoxy prepregs of M40 fade. The influence of volume fraction and fiber orientation of A17075/CFRP layer on flexural properties of A17075/CFRP laminate alternating A17075-T6 and carbon/epoxy prepreg was investigated. The results obtained from the experimental analysis are as follows: 1. In the $0^{\circ}$ fiber orientation, the mont of increase of the flexural rigidity was $20.5\%$ at the $26.5\%$ volume fraction and $38.0\%\;at\;the\;35.7\%$ volume fraction compared with the flexural rigidity level(20.0GPa) of the $10\%$ volume fraction of CFRP. 2. In the $\pm45^{\circ}$ fiber orientation the amount of decrease of the flexural rigidity was $23.5\%\;at\;the\;20.0\%$ volume fraction and $31.5\%\;at\;the\;33.3\%$ volume fraction compared with the flexural rigidity level of the $10\%$ volume fraction of CFRP. 3. In the $0^{\circ}$ fiber orientation, the flexural strength was 481.5MPa at the $10\%$ volume fraction of CFRP and 583.8MPa at the $26.5\%$ volume fraction and 653.7MPa at the $35.7\%$ volume faction. 4. In the $\pm45^{\circ}$ fiber orientation, the flexural strength was 354.0MPa at the $20.0\%$ volume fraction of CFRP and 340.5MPa at the $33.3\%$ volume fraction.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.289-292
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• 1995

Fig leaves were extracted with methanol and then fractionated with ethyl acetate and various buffers to get active fractions, and their antimicrobial activities in each fraction were determined. Acidic fraction and phenolic fraction of fig leaves showed strong antimicrobial activities, but the basic fraction and neutral fraction did not show any activities. The degree of antimicrobial activities in phenolic fraction against tested bacteria were higher than those in acidic fraction, but these against yeasts and mold were almost equivalent to those in acidic fraction. Especially, phenolic fraction showed the strongest activities against Staphylococcuns aureus and Pseudomonas aeruginosa. Although there were some differences among microorganisms, minimum inhibition concentrations(MIC) in acidic and phenolic fractions against tested microorganisms were 0.05 to 0.1 g eq./ml and 0.01 to 0.25 g eq./ml, on the basis of fresh sample weight, respectively. Minimum lethal concentrations(MLC) in acidic and phenolic fractions were 0.25 to 2.00 g eq./ml and 0.05 to 1.50 g eq./ml, respectively. These supposed the antimicrobial activities in phenolic fraction were generally higher than those in acidic fraction and also phenolic fraction had lower MIC and MLC values than acidic fraction.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.581-588
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• 2019

In this study, S. glauca (Bunge) Bunge extract was testified total polyphenol contents, electron donating ability on DPPH, and scavenging ability of superoxide anion radical and hydrogen peroxide. Total polyphenol contents of S. glauca (Bunge) Bunge extract were 7,053.30±915.93 ㎍ GAE/mL. In the fractions, fraction by ethanol was the highest content of 10,973.30±1,000.24 ㎍ GAE/mL. Fractions of ethyl acetate and water were 2,386.70±166.53 ㎍ GAE/mL, 2,413.30±41.63 ㎍ GAE/mL respectively. It was shown that total content of polyphenol according to solvent was significant relation at p<0.05. In the experiment of the electron donating ability, 70% ethanol extract and methylene chloride fraction were -246.15±24.17%, -254.01± 16.54% respectively. In case of ethyl acetate fraction, it was the highest electron donating ability to DPPH radical, 39.06±0.34%, and then water fraction of 36.71±5.55%, ethanol fraction of 29.77±2.57%, gradually. Electron donating abilities revealed significant difference (p<0.05) between the solvents. The superoxide radical scavenging ability of standard material was 0.029±0.0011; 70% ethanol extract of 0.022±0.00052, methylene chloride fraction of 0.027±0.00031, ethyl acetate fraction of 0.024±0.0011, ethanol fraction of 0.021±0.00024 and water fraction of 0.024±0.00019. Hydrogen peroxide scavenging ability of 70% ethanol extract was -0.0029±0.00040 and the others were as follow; methylene chloride fraction (-0.0042±0.00058), ethyl acetate fraction (-0.003± 0.0041), ethanol fraction (-0.0029±0.0015) and water fraction (-0.0028±0.00090).

• Journal of Elementary Mathematics Education in Korea
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• v.12 no.1
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• pp.59-78
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• 2008

The purpose of this study was to research and analyze students' informal knowledge before they learned formal knowledge about fraction concepts and to see how to apply this informal knowledge to teach fraction concepts. According to this purpose, research questions were follows. 1) What is the students' informal knowledge about dividing into equal parts, the equivalent fraction, and comparing size of fractions among important and primary concepts of fraction? 2) What are the contents to can lead bad concepts among students' informal knowledge? 3) How will students' informal knowledge be used when teachers give lessons in fraction concepts? To perform this study, I asked interview questions that constructed a form of drawing expression, a form of story telling, and a form of activity with figure. The interview questions included questions related to dividing into equal parts, the equivalent fraction, and comparing size of fractions. The conclusions are as follows: First, when students before they learned formal knowledge about fraction concepts solve the problem, they use the informal knowledge. And a form of informal knowledge is vary various. Second, among students' informal knowledge related to important and primary concepts of fraction, there are contents to lead bad concepts. Third, it is necessary to use students' various informal knowledge to instruct fraction concepts so that students can understand clearly about fraction concepts.

• Journal of the Korean School Mathematics Society
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• v.25 no.4
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• pp.307-332
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• 2022

This action research was carried out to help students learn fractions computation by making and using semi-concrete fraction manipulatives that can be used continuously in math classes. For this purpose, the researcher and students made semi-concrete fraction manipulatives and learned how to use these through reviewing the previously learned fraction contents over 4 class sessions. Afterward, through the 14 classes (7 classes for learning to reduce fractions and to a common denominator, 7 classes for adding and subtracting fractions with different denominators) in which the principle inquiry learning model was applied, students actively engaged in learning activities with fraction manipulatives and explored the principles underneath the manipulations of fraction manipulatives. Students could represent various fractions using fraction manipulatives and solve fraction computation problems using them. The achievement evaluation after class found that the students could connect the semi-concrete fraction manipulatives with fraction representation and symbolic formulas. Moreover, the students showed interest and confidence in mathematics through the classes using fraction manipulatives.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.591-599
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• 2015

Cercidiphyllum japonicum leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. A portion of EtOAc fraction (10 g) was chromatographed on a Sephadex LH-20 column, by the successively elution with various aqueous $MeOH-H_2O$ (1:9, fraction $1-2{\rightarrow}3:7$, fraction $3-5{\rightarrow}1:1$, fraction $6-9{\rightarrow}7:3$, fraction $10-13{\rightarrow}9:1$, fraction 14-16). Compound 2 was isolated from fraction 6 and compound 1 was separated from fraction 11 and 12. Compound 3 and 4 were purified from fraction 13. The isolated compounds were elucidated as quercetin-3-O-${\alpha}$-L-rhamnopyranoside (1), chlorogenic acid (2), quercetin-3-O-${\alpha}$-L-arabinofuranoside (3) and quercetin-3-O-${\beta}$-D-xylopyranoside (4) by the spectral and literature data, and by comparison with the authentic samples. These compounds were reported, for the first time, from the extracts of C. japonicum leaves. Also chlorogenic acid (2) has never been reported before in domestic tree species and can be used as an index compound for C. japonicum.

• Journal of Nutrition and Health
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• v.31 no.6
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• pp.1076-1081
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• 1998

The purpose of this research was to isolate an active component on immunoytes from 70% MeOH extract of Codonopsis lanceolatae Radix(CLE). CLE was fractionated successively with hexane, methylene chloride, n-butyl alcohol and water, and then the water fraction was separated with molecularporous membrane tubing(m.w. 3,500). Each fraction(50mg/kg) was administered p.o. once a day for 7 days in BALB/c mice respectively. None of these fractions affected the apoptosis and mitochondrial transmembrane potential in thymocyte. Hexane and methylene chloride fractions decreased CD4$^{[-10]}$ CD8$^{+}$ single-positive cells, and the water fraction enhanced CD4$^{+}$ CD8$^{[-10]}$ single-positive cells in thymocyte. The proliferation of thymocytes was decreased by the fraction hexane, but was enhanced by the water fraction. Hexane, methylene chloride and butyl alcohol fractions suppressed the production of nitric oxide, which was not affected by the water fraction. Hexane and butyl alcohol fraction suppressed the phagocytic activity, but water fraction enhanced it. The components(m.w. 3,500 above) separated from the water fraction enhanced the proliferation of thymocyte, the population of CD4$^{+}$ CDB$^{[-10]}$ single-positive cells, and phagocytic activity in macrophage. These results suggest that the stimulative components of proliferation, TH population and phagorytc activity is in the water fraction, and the molecular weight is 3,500 above. (Korean J Nutrition 31(6) : 1076~1081, 1998) 1998)

• Toxicological Research
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• v.13 no.4
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• pp.311-316
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• 1997

This study was carried out to develop antitumor effect of the n-butanol soluble fraction of Perilla frutescens on (KB cells) human oral epitheloid carcinoma cells. The cytotoxictty of methanollc extract of Perilla frutescens on KB cells was evaluated by 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide(MTT) assay. The antitumor activity of various fractions obtained from n-butanol soluble fraction of Perilla frutescens was evaluated in human oral epithelold carcinoma cells. The antitumor acavity of the n-butanol soluble fraction on human oral epitheloid carcinoma cells was evaluated by MTT assay of colorimetric method. The light microscopic study was carried out to observe morphological changes of cultured human oral epitheloid carcinoma cells. These results were obtained as follows; 1. The fractions 1,2 and 3 of the n-butanol soluble fraction of Perilla frutescens were shown significant antitumor activities. 2. The number of human oral epitheloid carcinoma cells were decreased and tend to form cell cluster by treatment with fractions 1,2,3 and 4 of the n-butanol soluble fraction of Perilla frutescens. 3. The fraction 1 of the n-butanol soluble fraction of Perllla frutescens showed the highest antitumor activity on Perilla frutescens. It has been selected as a lead fraction for further examinations.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.244-249
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• 2005

To investigate the effect of Holstein colostrum peptide fraction on proliferation of immune cell, polypeptide fractions were separated from acid whey into 3 fractions depending on molecular weight by ultrafiltration: Fraction I, which contains the polypeptide larger than 10,000 Da, Fraction n, which contains the polypeptide ranging from 1,000 Da to 10,000 Da and Fraction III, which contains the polypeptide smaller than 1,000 Da. EL-4 cell (murine T lymphoma cell) was used to evaluate immune enhancing effect of each fraction from Holstein colostrum. Fraction n showed the highest proliferative effect of the colostrum whey fractions on EL-4 cell at 1mg/mL compared with whole whey and other fractions and this proliferative activity was shown in dose dependent manner. Fraction n showed the highest proliferative effect on PMA (Phorbol 12-myristate 13-acetate) stimulated EL-4 cell. Heated Fraction n showed similar effect to native one on proliferation of both EL-4 cell and PMA stimulated EL-4 cell.