• 생약학회지
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• 제44권1호
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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.

• 한국결정성장학회지
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• 제7권3호
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• pp.473-480
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• 1997

소결조제로 $Al^2O^3$와$Y^2O^3$를 첨가한 $\beta$-SiC 분말에 seed로서 1 wt% 및 wt%$\beta$-SiC 휘스커를 첨가한 시편과 첨가하지 않은 시편을 $1850^{\circ}C$ 에서 5-10 시간 동안 열처리를 행하였다. Seed로서 1-3 wt% $\beta$-SiC 휘스커의 첨가는 액상소결 탄화규소의 미세구조와 기계적특성에 의미 있는 영향을 미치지 않았다. 이는 $\beta$-SiC 휘스커가 액상이 존재하는 고온가압소결 조건에서 불안정하기 떼문이라고 생각된다. $\beta$-SiC 휘스커를 1 wt% 첨가하여 $1950^{\circ}C$에서 5시간 동안 열처리한 시편의 강도 및 파괴인성은 각각 465 MPa 및 5.8 MPa $m^{1/2}$이었고, 동일조건에서 제조된 $\beta$-SiC 휘스커를 펌가하지 않은 시편의 강도 및 피괴인성은 각각 451 MPa 및 5.5 MPa $m^{1/2}$이었다.

• 대한화학회지
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• 제31권4호
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• pp.369-372
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• 1987

벤조일아세톤과 벤즈알데히드 유도체 및 피페리딘으로부터 다섯가지의 N-(2-아세틸-2-벤조일-1-페닐에틸) 피페리딘 유도체(2a-2e)를 합성하였다. 이 유도체들로 부터 다섯가지 ${\beta}$-아세틸-${\beta}$-벤조일스티렌 유도체(3a-3e)를 합성하였다. 이 화합물들의 구조를 원소분석 ir 및 nmr 스펙트럼으로 확인하였다.

• 생약학회지
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• 제27권4호
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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.

• 생약학회지
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• 제21권1호
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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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• 제4권4호
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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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• 제47권4호
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• pp.384-389
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• 2004

$100^{\circ}C$에서 반응시켜 2, 4, 6, 8시간의 갈변도 변화는 ${\beta}-1,4-mannobiose$와 urea의 반응혼합물이 시간의 경과함에 따라 강한 착색도의 증가를 나타냈으나 phenylthiourea, thiourea의 반응액은 착색속도가 늦었다. 같은 조건하에서 $Gal^3Man_4$와 urea 관련화합물의 각 반응혼합물의 갈변도를 나타낸 것으로 urea가 강한 착색도의 중가를 보였고 phenylthiourea, thiourea의 반응액은 비교적 높은 착색도를 보였다. DP 7의 galactosyl mannooligosaccharide와의 각 반응혼합물의 갈변도는 urea의 반응액이 강한 착색을 보였으며 phenylthiourea, thiourea의 반응액의 순으로 착색를 나타내었다. 반응혼합물의 TLC 결과에서 ${\beta}-1,4-mannobiose$와 urea의 반응혼합물 이외에 phenylthiourea, thiourea의 반응액은 새로운 화합물이 생성되었고, $Gal^3Man_4$와 D.P 7 galactosyl manooligosaccharide와의 반응혼합물에서는 모든 반응액에서 새로운 화합물이 출현되었다. 반응혼합물의 환원력은 urea관련화합물 중에서 특히 phenylthiourea, thiourea가 ${\beta}-1,4-mannobiose,\;Gal^3Man_4$, DP 7의 galactosyl manooligosaccharide와의 반응혼합물에서 강한 환원력이 나타났다. Linoleic acid에 대한 반응혼합물의 항산화력 측정에서 ${\beta}-1,4-mannobiose$와 thiourea의 반응혼합물의 항산화력이 Ascorbic acid(AsA)수준의 항산화력을 나타내었고, $Gal^3Man_4$와 thiourea, phenylthiourea의 반응혼합물은 AsA와 유사한 항산화능을 나타내었다. DP 7의 galactosyl manooligosaccharide와 thiourea, phenylthiourea의 반응혼합물의 항산화력은 AsA에 미치지는 못하였다. ${\beta}-1,4-Mannobiose$와 thiourea, phenylthiourea의 반응혼합물이 강한 전자공여능을 나타내고 있고, $Gal^3Man_4$와 phenylthiourea의 반응혼합물 및 D.P 7의 galactosyl manooligosaccharide와 phenylthiourea와의 반응혼합물이 전자공여능을 나타내고 있다.

• 한국세라믹학회지
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• 제32권4호
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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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• 제3권4호
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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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• 제52권6호
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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.