• Korean Journal of Pharmacognosy
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• v.44 no.1
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• pp.16-21
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• 2013

The fruits of Pourthiaea villosa were extracted with methanol and its extract was fractionated with n-hexane, methylene chloride, ethyl acetate and n-butanol. Repeated column chromatography of silica gel, sephadex LH-20 and HPLC led to the isolation of nine phenolic compounds from ethyl acetate soluble fraction. The chemical structures were elucidated as kaemferol-3-O-${\beta}$-D-glucopyranoside (astragalin) (1), isorhamnetin-3-O-${\beta}$-D-glucopyranoside (2), kaempferol-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-${\alpha}$-L-rhamnopyranoside (3), caffeic acid (4), quercetin-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-a-L-rhamnopyranoside (5), quercetin-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-${\beta}$-D-glucopyranoside (6), quercetin-3-O-${\beta}$-D-xylopyranosyl($1{\rightarrow}2$)-${\beta}$-D-galactopyranoside (7), quercetin-3-O-${\alpha}$-L-rhamnopyranoside (quercitrin) (8), and kaempferol-3-O-${\alpha}$-L-rhamnopyranoside (afzelin) (9) by spectroscopic techniques. These compounds were isolated from this plant for the first time.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.473-480
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• 1997

$\beta-SiC$powder with or without the addition of 1-3 wt% of $\beta-SiC$ whiskers (seeds) was hot-pressed at $1850^{\circ}C$ for 1 h using $Al_2O_3$ and $Y_2O_3$ as sintering aids. The hot-pressed materials were subsequently annealed at $1950^{\circ}C$ to enhance grain growth. The introduction of $\beta-SiC$ whiskers into $\beta-SiC$ does not affect the microstructure as well as mechanical properties significantly because the whiskers are not viable in the presence of liquid phase during hot-pressing. The strengths and fracture toughnesses of the hot-pressed and subsequently 5 h-annealed materials with 1 wt% $\beta-SiC$ whiskers and without $\beta-SiC$ whiskers were 465 MPa and 5.8 MPaㆍ$m^{1/2}$, and 451 MPa and 5.5 MPaㆍ$m^{1/2}$, respectively.

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.369-372
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• 1987

Five N-(2-acetyl-2-benzoyl-1-phenylethyl) piperidine derivatives (2a-2e) were synthesized from piperidine, benzoylacetone and benzaldehyde derivatives. Five ${\beta}$-acetyl-${\beta}$-benzoylstyrene derivatives (3a-3e) were synthesized from their adducts of piperidine derivatives. The structures of these compounds were confirmed by means of elemental analyses, ir and nmr spectra.

• Korean Journal of Pharmacognosy
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• v.27 no.4
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• pp.336-341
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• 1996

The roots of Korean Astragalus membranaceus Bunge. (Leguminosae), Astragali Radix, were extracted following general methods. During these extractions, first of all, 1,2-benzendicarboxylic acid diisononylester(compound A), ${\beta}-sitosterol(compound\;B)$, $3-0-{\beta}-D-galactopyranosyl-{\beta}-sitosterol(compound\;C)$ and $stigmast-4-en-6{\beta}-ol-3-one(compound\;D)$ were isolated. Three of these compounds were identified the first time isolation from the genus of Astragalus.

• Korean Journal of Pharmacognosy
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• v.21 no.1
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• pp.56-59
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• 1990

n-Alkanes (n-nonacosane and n-hentriacontane), phytosterols (campesterol and ${\beta}$-sitosterol) and phytosteryl glucosides (${\beta}$-sitosterol 3-O-${\beta}$-D-glucopyranoside and campesterol 3-O-${\beta}$-D-glucopyranoside) were isolated from the underground parts of Epimedium koreanum (Berberidaceae) and characterized by spectral data.

• Natural Product Sciences
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• v.4 no.4
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• pp.268-273
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• 1998

Two new triterpenoid saponins, named segetoside D and E, have been isolated from the seeds of Vaccaria segetalis. On the basis of chemical reactions and spectral data, structures of segetoside D and E have been established as: $28-O-[{\beta}-D-xylopyranosyl-(1{\rightarrow}4)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)]-[5-O-acetyl-{\alpha}-arabinofuranosyl(1{\rightarrow}3)]-[4-O-acetyl-{\beta}-D-fucopyranosyl]-quillaic\;acid-3-O-[{\beta}-D-galactopyranosyl(1{\rightarrow}2)]6-O-methyl\;ester-{\beta}-D-glucuronopyranoside$ and $28-O-[{\beta}-D-xylopyranosyl-(1{\rightarrow}4)-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)]-[5-O-acetyl-{\alpha}-arabinofuranosyl(1{\rightarrow}3)]-[4-O-acetyl-{\beta}-D-fucopyranosyl]-quillaic\;acid\;-3-O-[{\beta}-D-galactopyranosyl(1{\rightarrow}2)]-6-O-n-butyl\;ester-{\beta}-D-glucuronopyranoside$, respectively.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.384-389
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• 2004

The purified ${\beta}-mannanase$ hydrolyzed various gums to mannose, ${\beta}-1,4-mannobiose$, $Gal^3Man_4$, and D.P 7 of galactosyl mannooligosaccharide, and isolated from the enzymatic hydrolysate for 24 hrs reaction by activated carbon column chromatography and Sephadex G-25 column chromatography. For the elucidate of antioxidant action of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ and DP 7 of galactosyl mannooligosaccharide and urea derivatives, coloration, reducing power, antioxidant activity and DPPH test were accomplished. The coloration was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and urea. TLC of reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and ureas showed new reaction products, respectively. but except reaction mixture of ${\beta}-1,4-mannobiose$ and urea. The reducing power was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and phenylthiourea. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea showed similar radical scavenging activities on DPPH to activity of AsA. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea, phenythiolurea shown strong antioxidative activites on the oxidation of linoneic acid.

• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.455-461
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• 1995

To investigate the synthesis of $\beta$-Al2O3 and its crystallization behavior by oxalate coprecipitation method, the optimum pH range for oxalate coprecipitates has been theoretically calculated from the solubility products and the equilibrium constans of each metal ionic species and their solubility diagram wa obtained. The optimum pH range for oxalate coprecipitates at room temperature was estimated as <4. In experiment, we found that the optimum condition for oxalate coprecipitates was pH<1, which was not doped with pH controller. The Na+ ions were easily exchanged for the NH4+ ions of NH4OH which was used as pH controller, and those NH4+ ions were supposed to affect the crystallization behavior of $\beta$-Al2O3. The thermal decomposition of all complexes was almost complete below 40$0^{\circ}C$. The primary product of the decomposition process was m-Al2O3, which transformed to $\beta$"- or $\beta$-Al2O3 at temperature higher than 100$0^{\circ}C$. We found that the powder prepared at 120$0^{\circ}C$ had only $\beta$"- and $\beta$-Al2O3.EX>-Al2O3.

• Preventive Nutrition and Food Science
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• v.3 no.4
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• pp.382-386
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• 1998

A soluble dietary fiber, $\beta$-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of $\beta$-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% $\beta$-glucan. $\beta$-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of kernel. Various procedures have been developed for increasing the extraction yield of $\beta$-glucan. Oat gum prepared with weak alkali extractionand alcohol proecipitation following protein removal usually contains 80% $\beta$-glucan.The most commonly used method for $\beta$-glucan quantitiation is an enzymatic procedure combining lichenase plus $\beta$-glucosidase followed by measuring the amount of glucos released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of $\beta$-glucan is due to the increase in viscosity of the aqueous phase. Therefore, $\beta$-glucan shows great potentials as a thickener and a stabilizer.

• BMB Reports
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• v.52 no.6
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• pp.391-396
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• 2019

Receptor activator of nuclear factor kappa B ligand (RANKL) expression in osteoblasts is regulated by 1,25-dihydroxyvitamin D3 (1,25D3). CCAAT/enhancer-binding protein beta ($C/EBP{\beta}$) has been proposed to function as a transcription factor and upregulate RANKL expression, but it is still uncertain how $C/EBP{\beta}$ is involved in 1,25D3-induced RANKL expression of osteoblasts. 1,25D3 stimulation increased the expression of RANKL and $C/EBP{\beta}$ genes in osteoblasts and enhanced phosphorylation and stability of these proteins. Moreover, induction of RANKL expression by 1,25D3 in osteoblasts was downregulated upon knockdown of $C/EBP{\beta}$. In contrast, $C/EBP{\beta}$ overexpression directly upregulated RANKL promoter activity and exhibited a synergistic effect on 1,25D3-induced RANKL expression. In particular, 1,25D3 treatment of osteoblasts increased $C/EBP{\beta}$ protein binding to the RANKL promoter. In conclusion, $C/EBP{\beta}$ is required for induction of RANKL by 1,25D3.