• Applied Biological Chemistry
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• 제43권2호
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• pp.136-140
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• 2000

방울비짜루의 MeOH 추출물 및 수포화 BuOH추출물로부터 항균활성을 확인하고 그 원인물질을 구명하던 중 두 종의 steroid saponin을 분리하였다. 이들의 구조확인을 위해 $^1H,\;^{13}C$ NMR 및 2D NMR 등 분광학적 방법을 사용하였으며 최종 이들의 구조가 25S-spirostane계의 steroid saponin인$3-O-[{\beta}-D-glucopyranosyl-(1{\rightarrow}2)-{\beta}-D-glucopyranosyl]-(25S)-spirostan-3{\beta}-ol$ 및 $3-O-{{\beta}-D-glucopyranosyl-(1{\rightarrow}2)-[{\beta}-D-xylopyranosyl-(1{\rightarrow}4)]-{\beta}-D-glucopyranosyl}-(25S)-spirostan-3{\beta}-ol$인 것으로 동정되었다. 이 두 화합물은 방울비짜루로부터는 처음으로 분리되었다. 이들 saponin의 항균활성 및 항균 스펙트럼을 검사하기 위하여 20개 균주에 대한 MIC를 실시하였다. 이들은 그중 10개 균주에 대해 $100\;{\mu}g/ml$의 농도에서 세균의 성장을 저지하는 항균력이 있었으며 광범위한 항균 스펙트럼을 나타내었다.

• 한국식품조리과학회지
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• 제19권5호
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• pp.616-623
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• 2003

Bran(1∼5번)의 총 평균 $\beta$-glucan 함량은 5.52%로서 가장 높은 회수율 (48.5%)을 보인 추출 조건은 pH 10 및 45$^{\circ}C$, 다음은 pH 7 및 45$^{\circ}C$로 나타났다. 보리겨의 gum 물질은 배유 부분의 gum 물질과는 달리 상당량의 전분, 단백질이 혼입되어 있었고 정제된 $\beta$-glucan 도 단백질 및 전분 함량이 감소되긴 하였으나 호분층 안쪽의 bran 1,2,3,4에서도 $\beta$-glucan 함량이 78.2∼85.8%를 나타내어 세포벽의 peptide, arabinoxylan 등과 강하게 결합됨을 알 수 있었다. $\beta$-glucan을 이루는 구성당은 glucose가 주종이며, 그 외 arabinose, xylose, mannose, galactose였으며, 분자량은 보리겨에 따라 차이가 있으나 bran 1∼3의 경우 4.09 x $10^{5}$ 에서 4.41 x $10^{5}$ 정도의 분자량이 90% 이상을 차지하였으며, 다당 고유의 특성인 분자량의 분산성을 나타내었다. 한편 $\beta$-glucan의 구조 역시 보리겨에 따라 다소 차이가 있으나 $\beta$-(1\$\longrightarrow$3) 결합, $\beta$-(1\$\longrightarrow$4) 결합이 대부분을 차지하였고, $\beta$-glucan용액의 유동특성은 농도가 증가함에 따라 유동지수는 감소하여 의가소성이 증가하는 경향을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2801-2805
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• 2010

A nucleophilic substitution reaction of 4-chloro-7-nitrobenzofurazan (NBF-Cl) with anilines in MeOH-MeCN mixtures was conducted at 25, 35, and $45^{\circ}C$. Based on the higher $\beta_{nuc}$ values (1.0 - 1.6) of the reaction and a good correlation of the rate constants with the reduction potentials of the aniline nucleophiles, the present reaction was initiated by a single electron transfer (SET). After this step, the reaction proceeds through a transition state similar to the normal $S_NAr$-Ad.E pathway.

• Bulletin of the Korean Chemical Society
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• 제4권5호
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• pp.208-211
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• 1983

Kinetic studies of nucleophilic substitution reactions of para-substituted benzylchlorides with anilines were conducted in a range of MeOH-MeCN mixtures at $55.1^{\circ}C$. Hammett ${\rho}_C$, ${\rho}_N$ values and Bronsted ${\beta}$ values were determined, in other to examine the transition state variations caused by changes in nucleophiles, substituents and solvents properties (${\pi}^{\ast}$ and ${\alpha}$). Applications of potential energy surface (PES) and quantum mechanical (QM) models of transitheion state characterization lead us to conclude that the reaction proceeds via the dissociative $S_N2$ mechanism.

• Journal of the Korean Wood Science and Technology
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• 제41권2호
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• pp.149-157
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• 2013

The octopus type oligo-hydroxypropylene glycol ${\beta}$-D-glucopyranosides were successfully synthesized in this studies: the sterospecific compound of allyl 2, 3, 4, 6-tetra-O-acetyl-${\beta}$-D-glucopyranosides (1) was deacetylated with NaOMe in MeOH lead to allyl-${\beta}$-D-glucopyranoside (2) which was perallylated and followed by hydroboration and subsequent oxidation afforded (3-hydroxy-propyl) 2, 3, 4, 6-tetraO(3-hydroxy-propyl)-${\beta}$-D-glucopyranoside (4). As a result, not only allylpropylene glycol ${\beta}$-D-glucopyranosides (5, 7, and 9) but also hydroxypropylene glycol ${\beta}$-D-glucopyranosides (6, 8, and 10) were synthesized by repeated sequential perallylation followed by hydroboration/oxidation.

• 약학회지
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• 제50권1호
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• pp.47-51
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• 2006

The roots of Dipsacus asper are used in traditional Chinese medicine as an analgesic, enhancement of liver activity, an anti-inflammatory agent and the treatment of fractures. In order to investigate the antioxidative activity, Dipsaci Radix was extracted with MeOH and fractionated with $CHCl_3$, EtOAc, BuOH and water. MeOH ex. and its solvent fractions were determined on the free radical scavenging activity by DPPH method and antioxidative activity on low density lipoprotein oxidation. The EtOAc and BuOH fractions showed antioxidative activities and from their fractions, two compounds were isolated and identified as hederagenin 3-O-${alpha}$-L-arabino pyranoside (compound 1) and O-${\alpha}$-L-arabinopyranosyl hed-eragenin 28-O-${\beta}$-D-glucopyranosyl ($1{\to}6$)-${\beta}$-D-glucopyranosyl ester (compound 2). Saponin glycoside, compound I showed anti-oxidative activity.

• 한국가축번식학회지
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• 제21권4호
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• pp.335-343
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• 1997

The effect of thiol compounds on development and intracellular glutathione(GSH) concentrations of bovine embryos produced by in vitro maturation and in vitro fertilization(IVM/IVF) was examined in CRlaa medium with or without $\beta$-mercaptoethanol(0, 10, 25 and 50$\mu$MME) and cysteamine(0, 25, 50 and 75 $\mu$M). Numbers of cells comprising blastocysts were also counted using double fluorescence stain and the total glutathione levels(oxidized and reduced form) of morula and blastocyst embryos were than measured by an enzymatic method. Following routine IVM/IVF procedures oocytes and zygotes were cultured for 40 to 44h in CRlaa medium. Then 2 to 8-cell embyos had cumulus cell removed and were allotted randomly to the experimental medium. In Experiment 1, the proportion of embryos developing to and beyond morulae stages in 0, 10, 25 and 50 $\mu$M $\beta$-ME was 42.9%, 50.0%, 53.7% and 65.6%, respectively. Fifty $\mu$M $\beta$-ME group was significantly higher than those of any other groups (P<0.05). In Experiment 2, the percentages of embryos developed beyond morulae stages in 0, 25, 50 and 75 $\mu$M cysteamine was 42.9%, 40.4%, 60.0% and 59.2%, respectively. Fifty and 75$\mu$M cysteamine groups were significantly higher than in 0 and 25 $\mu$M cysteamine groups, but all of culture medium containing cysteamine(52.6%) was not significantly difference in control group(42.9%). In Experiment 3, the intracellular GSH concentrations of morulae and blastocyst embryos in 0 and 50 $\mu$M $\beta$-ME was 42.4 pM and 44.9 pM, 49.5 pM and 67.8 pM, respectively. Morulae embryos were not difference, but blastocyst embryos were significantly difference between treatments(P<0.05). In Experiment 4, the intracellular GSH concentrations of morulae in CRlaa with or without cysteamine were 39.8 pM and 45.6 pM, and blastocysts were 59.3 pM and 66.8 pM, respectively. Cell numbers of blastocysts were similar to in all experimental groups. These experiments indicate that thiol compounds can increase the proportion of embryos that developing to and beyond morulae stage and the intracellular GSH concentrations.

• Applied Biological Chemistry
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• 제49권1호
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• pp.82-85
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• 2006

산딸나무 열매를 100% MeOH로 추출하고, 얻어진 추출물을 EtOAc, n-BuOH 및 물로 용매 분획 하였다. 이 중 EtOAc 분획으로부터 silica gel과 octadecyl silica gel(ODS) column chromatography를 반복하여 3종의sterol 화합물을 분리, 정제하였다. 각 화합물의 화학구조는 NMR, MS 및 IR 등의 스펙트럼 데이터를 해석하여, ${\beta}-sitosterol$(1), $stigmast-4-en-6{\beta}-ol-3-one$(2), daucosterol(3)으로 동정하였다. 이 화합물들은 산딸나무에서 처음 분리되었다.

• 한국의학물리학회지:의학물리
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• 제3권1호
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• pp.9-18
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• 1992

4MeV X-선을 제조된 beta-eucryptite 에 조사시 킨 후, 300K-600K 온도 구간에서 열자극 방광을 측정하였다. 혼합되어 측정된 열자극발광 스펙트럼은 342K, 392K, 438K, 474K 과 572K 에서 열자극발광 peak가 나타난다. 527K 의 열자극방광 스펙트럼은 retrapping이 일어나는 2nd kinetic order 임을 알았다. Peak shape 법의 활성화에너지는 1.03eV이었고 이탈진 동수는 3.9$\times$$10^{8}$sec$^{-1}$이었다. 또한 initial rise법과 온도 상승률에 따른 활성화 에너지는 각각 1.19$\pm$0.03eV, 1.02$\pm$0.05eV로 나타났다. 최고의 열자극발광 세기를 갖는 온도 527K를 유지하고 측정한 isothermal decay 스펙트럼에 의한 이탈진동수는 heating rate법의 결과와 유사한 2.8$\times$$10^{8}$sec$^{-1}$이었다. 50Gy의 조사선량 범위까지는 조사선량에 따른 열자극발광 세기의 선형성이 유지되었지만, 그 이상의 영역에서는 supralinearity가 나타난 후 saturation되었다.

• Applied Biological Chemistry
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• 제41권2호
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• pp.197-200
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• 1998

홍화 MeOH 추출물의 n-BuOH 분획으로부터 silica gel column chromatography를 반복하여 2종의 flavonoid 배당체를 분리, 정제하였다. 화합문의 화학구조를 HMBC를 포함한 NMR, MS, IR과 같은 기기분석 결과와 산가수분해반응을 이용하여 결정, 각각 $3-O-[{\beta}-D-glucopyranosyl(1{\rightarrow}2)\;{\beta}-D-glucopyranosyl]\;kaempferol$ 및 $3-O-[{\alpha}-L-rhamnopyranosyl(1{\rightarrow}6)\;{\beta}-D-glucopyranosyl]\;kaempferol$로 동정하였다. 각 화합물은 Grb2-Shc 결합저해활성$(IC_{50}:43,\;47\;{\mu}g/ml)$을 나타내었다.