• Natural Product Sciences
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• v.26 no.3
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• pp.214-220
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• 2020

Brassica oleracea var. gongylodes (red kohlrabi) is a biennial herbaceous vegetable whose edible bulbotuber-like stem and leaves are consumed globally. Sliced red kohlrabi tubers were extracted using methanol and the concentrated extract was partitioned successively with dichloromethane (CH₂Cl₂), ethyl acetate (EtOAc), n-butanol (n-BuOH) and water (H₂O). Repeated column chromatography of EtOAc fraction through silica, sephadex LH-20 and RP-18 gel led to isolation of eleven compounds of which compound 1 was a new glycosylated indole alkaloid derivative, 1-methoxyindole 3-carboxylic acid 6-O-β-D-glucopyranoside. Others were known compounds namely, β-sitosterol glucoside (4), 5-hydroxymethyl-2-furaldehyde (5), methyl-1-thio-β-D-glucopyranosyl disulfide (6), 5-hydroxy-2-pyridinemethanol (7), (3S,4R)-2-deoxyribonolactone (8), n-butyl-β-D-fructopyranoside (9), uridine (10) and three fructose derivatives, D-tagatose (11), β-D-fructofuranose (12) and β-D-fructopyranose (13). Similarly, isolation from CH₂Cl₂ fraction gave two known indole alkaloids, indole 3-acetonitrile (2) and N-methoxyindole 3-acetonitrile (3). The structure elucidation and identification of these compounds were conducted with the help of ¹³C and ¹H NMR, HMBC, HMQC, EIMS, HR-ESIMS and IR spectroscopic data, and TLC plate spots visualization. Compounds 2, 3, 4, 5, 6, 7, 8 and 9 are noted to occur in kohlrabi for the first time. Different bioactivities of these isolated compounds have been reported in literature.

• Natural Product Sciences
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• v.15 no.1
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• pp.17-21
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• 2009

Column chromatographic separation of the alcoholic extract from the roots of Berberis amurensis yielded eight phenolic constituents including six lignans, hanultarin (1), (-)-secoisolariciresinol (3), (+)-lyoniresinol (5), (+)-syringaresinol (6), (+)-syringaresinol-O-$\beta$-D-glucopyranoside (7), liriodendrin (8), and two phenylpropanoids, 4-glucosyloxy-3-methoxyphenyl trans-propenoic ethyl ester (2), trans-ferulic acid (4). The structures were determined on the basis of NMR spectroscopic data. All isolated compounds(1-8) were reported for the first time from this source. Compound 1 exhibited moderate cytotoxicity against four human cancer cell lines in vitro using sulforhodamin B bioassay.

• Archives of Pharmacal Research
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• v.28 no.2
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• pp.195-202
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• 2005

Free radicals and reactive oxygen species (ROS) caused by UV exposure or other environmental factors are critical players in cellular damage and aging. In order to develop a new antiphotoaging agent, this work focused on the antioxidant effects of the extract of tinged autumnal leaves of Acer palmatum. One compound was isolated from an ethyl acetate soluble fraction of the A. palmatum extract using silica gel column chromatography. The chemical structure was identified as apigenin-8-C-beta-D-glucopyranoside, more commonly known as vitexin, by spectral analysis including LC-MS, FT-IR, UV, $^{1}H-$, and $^{13}C-NMR$. The biological activities of vitexin were investigated for the potential application of its anti-aging effects in the cosmetic field. Vitexin inhibited superoxide radicals by about $70\%$ at a concentration of $100\;{\mu}g/mL$ and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals by about $60\%$ at a concentration of $100\;{\mu}g/mL$. Intracellular ROS scavenging activity was indicated by increases in dichlorofluorescein (DCF) fluorescence upon exposure to UVB $20\;mJ/cm^2$ in cultured human dermal fibroblasts (HDFs) after the treatment of vitexin. The results show that oxidation of 5-(6-)chloromethyl-2',7'-dichlo-rodihydrofluorescein diacetate ($CM-H_{2}DCFDA$) is inhibited by vitexin effectively and that vitexin has a potent free radical scavenging activity in UVB-irradiated HDFs. In ROS imaging using a confocal microscope we visualized DCF fluorescence in HDFs directly. In conclusion, our findings suggest that vitexin can be effectively used for the prevention of UV-induced adverse skin reactions such as free radical production and skin cell damage.

• Korean Journal of Medicinal Crop Science
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• v.14 no.2
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• pp.77-81
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• 2006

As a result of cytotoxic compounds against cancer cell lines from natural sources, senven compounds were isolated from the leaf and twig of Acer okamotoanum Nakai. The compounds (1-7) were identified as ethyl gallate (1), methyl gallate (2), gallic acid (3), trans $resveratrol-3-O-{\beta}-D-glucopyranoside$ (4), acertannin (5), nikoenoside (6), and fraxin (7) by physicochemical and spectroscopic data (including mp, UV, IR, MS, $^1H-NMR,\;^{13}C-NMR$, DEPT, and HMBC) in comparison with those of published papers. All the compounds were tested for their cytotoxic activity against L1210, HL-60, K562, and B16F10 cancer cell lines in vitro by MTT assay method. Compounds 1-3 and 5 showed cytotoxic activity against all tested cell lines with $IC_{50}$ values ranged from 12.5 to $72.2\;{\mu}M$. Of the compounds, methyl gallate (2) exhibited the most potent cytotoxic activity against L1210, HL-60, K562, and B16F10 tumor cells with $IC_{50}$ values of 12.5, 48.3, 22.8, and $22.8\;{\mu}M$, respectively. Other compounds did not show any cytotoxic activity against four cancer cell lines.

• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.230-234
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• 2013

In the course of screening for antioxidant compounds by measuring the DPPH radical scavenging activity, a total extract of the aerial part of Trigonotis peduncularis (Boraginaceae) was found to show potent DPPH radical scavenging activity. Subsequent activity-guided fractionation of the methanolic extract of T. peduncularis led to the isolation of seven compounds, kaempferol (1), quercetin (2), trigonotin A (3), astragalin (4), trigonotin C (5), kaempferol-3-O-${\alpha}$-L-rhamnopyranosyl(1${\rightarrow}$6)-${\beta}$-D-glucopyranoside (6), and rutin (7) from the active ethyl acetate soluble fraction. Their structures were elucidated by spectroscopic studies. Among seven compounds, compounds 1, 2, 4, 6 and 7 were isolated for the first time from this plant, and compounds 2 and 7 showed the significant DPPH free radical scavenging activities.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.63-63
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• 2003

Opuntia ficus-indicavar. saboten Makino (Cactaceae) is a tropical or subtropical plant that has been widely used as folk medicine for the treatment of diabetes, asthma, burn, edema and gastritis. The purposes of the present study were to identify antioxidant constituents from fruits and stems of the plant cultivated in Cheju island, Korea, and examine their in vitro neuroprotective activities. Using a chromatographic fractionation method, ten chemical constituents were isolated from ethyl acetate extracts. By means of chemical and spectroscopic methods, those were identified as eight flavonoids such as kaempherol (a), quercetin (b), kaempferol 3-methyl ether (c), quercetin 3-methyl ether (d), narcissin (e), dihydrokaernpferol (f), dihydroquercetin (g) and erioclictyol (h), and two terpenoids such as 3-oxo-${\alpha}$-ionol-${\beta}$-d-glucopyranoside (i) and roseoside (j). Among the isolated compounds, comrounds c~e and h~j were those reported for the first titre from the plant. Compounds b, d and g showed DPPH free radical scavenging activities with IC$\sub$50/ values of 28, 19 and 31, ${\mu}$M respectively. Compounds d and g also inhibited iron-dependent lipid peroxidation with IC$\sub$50/ values of 2.4 and 3.5 ${\mu}$M. In a primary rat cortical neuronal cell culture system, compounds b, d and g inhibited xanthine/xanthine oxidase-induced (IC$\sub$50/ values of 18.2, 2.1 and 54.6 ${\mu}$M) and H$_2$O$_2$-induced (IC$\sub$50/ values of 13.6, 1.9 and 25.7 ${\mu}$M) cytotoxicities. In addition, compounds d and g inhibited NMDA-induced excitotoxicity by 21 and 33%, and only compound d inhibited growth factor withdrawal-induced apoptosis by 31% at a tested concentration of 3 ${\mu}$M. The results suggest that the antioxidant constituents with in vitroneuroprotective activities may serve as lead chemicals for the development of neuroprotective agent.