• Korean Journal of Pharmacognosy
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• v.48 no.4
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• pp.261-267
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• 2017

As part of the search for bioactive constituents of Korean medicinal plants, twelve steroids (1-12) were isolated from the rhizomes of Dioscorea nipponica. The isolated compounds were identified as diosgenin ($3{\beta}$, 25R)-spirost-5-en-3-ol (1), 25(R)-dracaenoside E (2), dioscin (3), gracillin (4), prosapogenin B (5), 25(R)-dracaenoside G (6), diosgenin 3-O-${\beta}$-D-glucopyranosyl($1{\rightarrow}3$)-${\beta}$-D-glucopyranoside (7), ophipogonin C′ (8), 7-oxodioscin (9), protodioscin (10), hypoglaucin F (11), and protoneogracillin (12). Their structures were characterized by spectroscopic data and identified by comparing these data with those in the literatures. All the isolates (1-12) were evaluated for their neuroprotective effects through induction of nerve growth factor in C6 glioma cells and effects on nitric oxide (NO) production in murine microglia cell line BV-2. Compounds 7 and 12 were found to induce upregulation of NGF secretion without causing significant cell toxicity and compound 4 exhibited potent anti-neuroinflammatory activity.

• Korean Journal of Pharmacognosy
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• v.48 no.4
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• pp.339-342
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• 2017

Quercus mongolica (QM) is a species of Quercus native to Eastern Mongolia, Siberia, China, Japan, and Korea. QM has been used as Korean traditional medicine for the treatment of inflammation of the skin. Present work, the validation and content determination of the phenolic compounds which were isolated from the leaves of QM, including pedunculagin (1) and kaempferol-3-O-(6"-galloyl)-${\beta}$-D-glucopyranoside (2) were conducted through High-Performance Liquid Chromatography (HPLC). As a result, the contents of these compounds were 4.14% and 0.76% in QM extract, respectively.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.485-488
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• 2007

Plentiful amount of spent yeast has been produced as a by-product from breweries. ${\beta}-Glucan$ was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude ${\beta}-glucan$ preparation consisted of mainly glucan (53% of total wt), containing approximately 35% ${\beta}-glucan$ content of total weight. The effects of crude ${\beta}-glucan$ substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast ${\beta}-glucan$ into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/${\beta}-glucan$ suspension than in flour/${\beta}-glucan$ suspension. It was suggested that preparation of yeast ${\beta}-glucan$ into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

• Journal of Sensor Science and Technology
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• v.25 no.5
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• pp.333-336
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• 2016

In this study, a beta monitoring sensor was developed as a part of basic research for quantitative beta monitoring underwater, and its performance was evaluated using a calibration source. A beta detection sensor was manufactured by using SiPM(silicon photomultiplier) and $CaF_2$:Eu, YAG:Ce, YAP:Ce scintillator. A large-area light guide was introduced to improve beta-ray detection efficiency. As calibration sources, the Beta source $^{90}Sr$, which is the main fission product of a nuclear accident, and the gamma source $^{137}Cs$ are used. In the performance evaluation, it is confirmed that scintillator $CaF_2:Eu$ gives the highest beta-ray detection response. Compared to gamma ray, beta-ray detection responsivity and detection efficiency are verified. Therefore, this study is expected to contribute to basic research in the development of an underwater beta-ray monitoring system.

• Natural Product Sciences
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• v.11 no.1
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• pp.13-15
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• 2005

Phytochemical study of the methanolic extract of Flaveria trinervia (Asteraceae) leaves has led to the isolation of three constituents characterised as 3,5,7,4' tetrahydroxy-6-methoxy flavone (6-methoxy kaempferol), oleanolic acid and ${\beta}-sitosterol-{\beta}-D-glucoside$. The identities of the compounds were confirmed by the physical and spectroscopic data and by comparison with authentic samples.

• Natural Product Sciences
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• v.11 no.1
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• pp.10-12
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• 2005

Flavonol galactosides were isolated from the EtOAc fraction of Artemisia apiacea by repeated column chromatography. Their structures were elucidated as $isorhamnetin-3-O-{\beta}-D-galactoside$ (1) and $quercetin-3-O-{\beta}-D-galactoside$ (2) by chemical and spectroscopic analysis. This is the first report on the isolation of compound 2 from this plant.

• The Korean Journal of Food And Nutrition
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• v.7 no.1
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• pp.23-28
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• 1994

Soybean $\beta$-amylase was purified by DEAE-cellulose ion exchange chromatography, Sephadex G-100 gel chromatography, CM Sephadex C-50 ion exchange chromatography and CM Sephadex C-50 ion exchange rechromatography The purified enzyme showed 1, 020 unit/mg of specific activity. The purified enzyme was identified as homogenious by disc PAGE and analysis of reaction product.

• The Korean Journal of Food And Nutrition
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• v.6 no.4
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• pp.307-313
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• 1993

Bacillus cereus $\beta$-amylase was purified by Sephadex G-100 gel filtration, CM Sephadex C-50 ion exchange chromatography and CM Sephadex C-50 ion exchange rechromatography The purified enzyme showed 871 unit/mg of specific activity. The purified enzyme was identified as homogenious by disc PAGE, SDS-PAGE and analysis of reaction product. The purified enzyme showed optimum pH 7.0. optimum temperature 5$0^{\circ}C$, and was stable at 0~5$0^{\circ}C$ and at pH range of 6~10.

• Communications of the Korean Mathematical Society
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• v.21 no.2
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• pp.363-374
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• 2006

A new bivariate beta distribution based on the Appell function of the third kind is introduced. Various representations are derived for its product moments, marginal densities, marginal moments, conditional densities and conditional moments. The method of maximum likelihood is used to derive the associated estimation procedure as well as the Fisher information matrix.

• Natural Product Sciences
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• v.17 no.4
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• pp.279-284
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• 2011

Phytochemical studies on the whole extract of Sedum hybridum L., a Mongolian medicinal plant, has been undertaken to isolate active principles responsible for its anti-oxidative and antibacterial activities. Eighteen known compounds, i.e. (1) quercetin, (2) kaempferol, (3) herbacetin-8-O-${\beta}$-D-xylopyranoside, (4) myricetin, (5) gossypetin-8-O-${\beta}$-D-xylopyranoside, (6) gallic acid, (7) 2,4,6-tri-O-galloyl-D-glucopyranose, (8) 6-O-galloylarbutin, (9) myricetin-3-O-${\alpha}$-L-arabinofuranoside, (10) quercetin-3-O-${\alpha}$-L-arabinofuranoside, (11) caffeic acid, (12) ethylgallate, (13) (-) epigallocatechin-3-O-gallate, (14) palmitic acid, (15) stearic acid, (16) stearic acid ethyl ether, (17) ${\beta}$-sitosterol and (18) ${\beta}$-sitosteryl-O-${\beta}$-D-glucopyranose have been isolated and their molecular structures identified by spectroscopic analysis. Thirteen substances including seven flavonol components (1, 2, 3, 4, 5, 9 and 10), five gallic acid derivatives (6, 7, 8, 12 and 13) and caffeic acid (11) exhibited significant, dose-dependent, DPPH radical scavenging activity. Galloyl esters 12 and 13 were revealed to be main active principles for the antibacterial property of the extract of Sedum hybridum L.