• Applied Biological Chemistry
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• v.44 no.3
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• pp.202-205
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• 2001

The root of Zingiber officinale R. was extracted with 80% aqueous MeOH, and the concentrated extract was fractionated with EtOAc, n-BuOH and water phases. The EtOAc fraction exhibited most potent antioxidant activity among them, and two active compounds were isolated by activity-guided separation using repetitive silica gel column chromatography. On the bases of spectral data and the chemical characteristics, the structure of the compounds were determined as 6-shogaol and 12-shogaol, respectively. The $EC_{50}$ values of them were evaluated as 26.4 ${\mu}M$ and 22.5 ${\mu}M$, respectively, where these values were higher than the commercial antioxidants, such as, BHA, BHT and ${\alpha}-tocopherol$.

• Journal of Applied Biological Chemistry
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• v.53 no.4
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• pp.207-211
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• 2010

The sprouts of Brassica oleracea var. gongylodes were extracted with 100% MeOH and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc fraction, three sterols were isolated through the repeated silica gel and ODS column chromatographies. On the basis of physico-chemical and spectroscopic data including NMR, MS, and IR, the chemical structures of the sterols were determined as ${\beta}$-sitosterol (1), brassicasterol (2), and 7-ketobrassicasterol (3). Compound 1 is usually observed in plant. Compounds 2 is observed in Brassica sp., and compounds 3 have very rarely occurred in natural source including plant.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.82-85
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• 2006

The fruits of Cornus kousa Burg. were extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc fraction, three sterols were isolated through the repeated silica gel and ODS column chromatographies. According to the results of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as ${\beta}-sitosterol$ (1), $stigmast-4-en-6{\beta}-ol-3-one$ (2) and daucosterol (3). They were the first to be isolated from Cornus kousa Burg.

• Applied Biological Chemistry
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• v.47 no.3
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• pp.357-360
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• 2004

The flower of Campsis granudiflora K. Schum. was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$. From the EtOAc fraction, four compounds were isolated through the repeated silica gel and ODS column chromatographies. From the result of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as linolenic acid methyl ester, linoleic acid methyl ester, ${\beta}-sitosterol$ and daucosterol. Daucosterol inhibited FPTase activity with $IC_{50}$ values of $14{\pm}0.04\;{\mu}M$.

• Journal of Applied Biological Chemistry
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• v.58 no.3
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• pp.237-240
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• 2015

The flowers of Chionanthus retusus Lindl. & Paxton were extracted with 80% aqueous MeOH at room temperature. The concentrated extract was partitioned as EtOAc, n-BuOH, and $H_2O$ fractions. From the EtOAc fraction, two triterpenoids and two sterols were isolated using the repeated silica gel ($SiO_2$) and octadecyl $SiO_2$ (ODS) column chromatographies. According to the results of physico-chemical and spectroscopic data including nuclear magnetic resonance, mass spectrometry, and infrared. The chemical structures of the compounds were respectively determined as ursolic acid (1), corosolic acid (2), ${\beta}$-sitosterol (3), and daucosterol (4). All the compounds were isolated for the first time from the flowers of Chionanthus retusus Lindl. & Paxton.

• Applied Biological Chemistry
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• v.40 no.6
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• pp.583-587
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• 1997

The MeOH extracts obtained from the tuber of Ipomoea batatas Lam. were solvent-fractionated with EtOAc, n-BuOH, and $H_2O$, respectively. From EtOAc fraction four different compounds were isolated through the repeated silica gel column chromatographies. From not only the results of NMR and MS data but also the adaptation of hydrolysis, methylation, and acetylation, the chemical structures of compounds were elucidated as resin glycoside, simonin I, ${\beta}-sitosterol$, and two kinds of unsaturated fatty acids.

• Applied Biological Chemistry
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• v.47 no.4
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• pp.422-425
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• 2004

The flower of Erigeron annuus L. was extracted with 80% aqueous MeOH, and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2O$, successively. From the EtOAc fraction, three compounds were isolated through the repeated silica gel, ODS column and high performance liquid chromatographies. From the result of physico-chemical data including NMR, MS and IR, the chemical structures of the compounds were determined as ${\alpha}-amyrenone,\;{\alpha}-amyrin\;and\;{\beta}-amyrin$. These three compounds were isolated for the first time from the flower of Erigeron annuus L.

• Journal of Korea Foresty Energy
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• v.21 no.1
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• pp.56-64
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• 2002

2kg of the dried leaves of Thuja orientalis Linnaeus were ground, extracted with acetone-$H_2O$(7:3, v/v), concentrated, and fractionated with a series of hexane, $CH_2C1_2$ EtOAc and water on a separators funnel. Each fraction was freeze dried to give dark-brown powder and a EtOAc soluble portion. of the powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluents. Spectrometric analyses such as NMR and FAB-MS including TLC were performed to characterize the structures of isolated compounds. The leave of Thuja orientalis Linnaeus contained a large amount of flavononol derivatives such as quercetin-3-O-$\alpha$-L-rhamnopyranoside and myricetin-3-O-$\alpha$-L-rhamnopyranoside in addition to a small amount of flavan compounds such as (+)-catechin and (+)-gallocatechin. The antioxidative activities of each fractions and isolated compounds were done by DPPH radical scavenging test, and all of them were indicated strong antioxidative activities.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.155-158
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• 2016

The fruits of Prunus davidiana were extracted with 80 % aqueous methanol at room temperature. The concentrated extract was partitioned as ethyl acetate (EtOAc), n-butyl alcohol, and water fractions. From the EtOAc fraction, three triterpenoids were isolated through the repeated silica gel ($SiO_2$) and octadecyl $SiO_2$ column chromatographies. Based on physico-chemical and spectroscopic data including nuclear magnetic resonance, mass spectrometry, and infrared, the compounds were identified to be ursolic acid (1), corosolic acid (2), and ${\alpha}-amyrin$ (3).

• Applied Biological Chemistry
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• v.50 no.1
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• pp.53-56
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• 2007

The aerial parts of Artemisia princeps PAMPANINI were extracted with 80% aqueous MeOH and the concentrated extract was partitioned with EtOAc, n-BuOH and $H_2$O, successively. From the EtOAc fraction, five compounds were isolated through the repeated silica gel and ODS column chromatog-raphies. They were determined as friedelin (1), ${\beta}$-amyrin (2), ${\beta}$-amyrin acetate (3), camphanediol (4) and hispidulin (5) on the basis of spectral data, respectively.