• Archives of Pharmacal Research
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• v.23 no.3
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• pp.237-239
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• 2000

The antioxidant activity of Artemisia montana was determined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibitory activity against free radical generation of hepatocytes ($AC_2$F). The methanol extract of A. montana showed strong radical scavenging activity at a concentration of $10.1{\mu}g/m{\ell}$, and thus fractionated by solvent extraction. Esculetin and luteolin 7-O-rutinoside (scolymoside) were isolated as the active principles from the EtOAc and interphase fractions, respectively. The antioxidant activity of these compounds were comparable to that of L-ascorbic acid.

• Korean Journal of Pharmacognosy
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• v.26 no.4
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• pp.337-343
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• 1995

Two flavone glycosides were isolated from the aerial part of Angelica keiskei Koidz and identified by means of spectral analysis as luteolin-$7-O-{\beta}-{_D}-glucoside$ and Iuteolin-7-O-rutinoside. Intraperitoneal administration of methanolic extract(100mg/kg) and $luteolin-7-O-{\beta}-{_D}-glucoside(5mg/kg)$ isolated from this plant produced a significant hypolipemic activity.

• Natural Product Sciences
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• v.17 no.4
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• pp.367-371
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• 2011

Effects of the extract and fractions from Parasenecio pseudotaimingasa on rat lens aldose reductase (AR) inhibition have been investigated. Among them, the n-BuOH fraction was exhibited good inhibitory potencies ($IC_{50}$ value 1.42 ${\mu}g/ml$). Phytochemical constituents were isolated from the n-BuOH fraction by open column chromatography. Their structures were elucidated as luteolin-7-O-rutinoside (1) and luteolin-7-Oglucoside (2) on the basis of spectroscopic analysis. Compounds 1 and 2 exhibited strong AR inhibitory activity, with $IC_{50}$ values of 2.37 and 1.05 ${\mu}M$, respectively. This is the first report on the isolation of compounds 1 and 2 from P. pseudotaimingasa. These results suggest that P. pseudotaimingasa could be a useful material in the development of a novel AR inhibitory agent against diabetic complications.

• Natural Product Sciences
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• v.17 no.3
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• pp.221-224
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• 2011

A $CH_3Cl$ extract from the flower of Lonicera japonica (Lauraceae) significantly protected primary cultures of rat cortical cells injured by the excitotoxic amino acid, L-glutamate. Loganin (1), secoxyloganin (2), caffeic acid (3) rutin (4), hyperoside (5), quercetin-3-O-glucoside (6), lonicerin (7), kaempferol-3-O-rutinoside (8), luteolin-7-O-b-D-glucopyranoside (9), quercetin (10) and luteolin (11) were isolated by bioactivity-guided fractionation from the $CH_3Cl$ fraction and further separated using chromatographic techniques. Caffeic acid, lonicerin, kaempferol-3-O-rutinoside, quercetin and luteolin had significant neuroprotective activities against glutamate-induced neurotoxicity in primary cultures of rat cortical cells at concentrations ranging from $0.1{\mu}M$ to $10.0\;{\mu}M$.

• Natural Product Sciences
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• v.18 no.1
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• pp.39-46
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• 2012

In Korea, the leaves of Sonchus brachyotus (Compositae), an edible mountainous vegetable, are traditionally used to treat hepatitis and hemorrhage and are known to have diuretic action. The aqueous ethanolic extract of this plant was selected in our screening experiment using the peroxynitrite ($ONO_2^-$)-scavenging assay, and the present study was performed to qualitatively and quantitatively identify the active compounds from S. brachyotus and validate the present high-permormance liquid chromatography (HPLC) coupled with ultraviolet absorption detection method based on accuracy, precision and repeatability. Five phenolic substances including the main compound, luteolin $7-O-{\beta}-D$-glucuronopyranoside, as well as chlorogenic acid, luteolin 7-O-rutinoside, luteolin $7-O-{\beta}-D$-glucopyranoside, and luteolin, were found in the aqueous ethanolic extract of S. brachyotus. In the HPLC validation experiment, the linearity of the four compounds was established by $R^2$ values of more than 0.999 within the test ranges, and the recovery rate ranged from 98.2 - 105.3%. Luteolin 7-O-glucuronide was a predominant compound (143 mg/g of extract and 18.3 mg/g of the dry weight of plant material) with a potent peroxynitrite-scavenging effect ($IC_{50}$, $1.02{\pm}0.08{\mu}M$). Luteolin and its three glycosides together with chlorogenic acid were qualitatively and quantitatively determined using an HPLC method validated in the present study.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.58-63
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• 2005

Ethyl acetate-soluble neutral fraction of hot water extracts from the aerial parts of Angelica keiskei showed a 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Six antioxidative compounds were purified and isolated by various chromatographic procedures. Based on the analyses of FAB-MS and NMR, the isolated compounds were structurally elucidated as luteolin 7-O-${\beta}$-D-glucopyranoside (1), quercetin 3-O-${\beta}$-D-galactopyranoside (2), quercetin 3-O-${\beta}$-D-glucopyranoside (3), quercetin 3-O-${\alpha}$-D-arabinopyranoside (4), kaempferol 3-O-${\alpha}$-D-arabinopyranoside (5), and luteolin 7-O-rutinoside (6). The glycosides of flavonols and luteolin showed DPPH radical-scavenging activity. One molecule of 2, 3, 4, 6, 1, and 5 scavenged 4.2, 4.2, 4.1, 2.5, 2.2, and 1.4 molecules of DPPH radical, respectively.

• Natural Product Sciences
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• v.19 no.3
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• pp.231-235
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• 2013

Activity-guided isolation to search for antifibrotic compounds from natural products using HSC-T6 cells afforded nine flavonoids or phenolics, luteolin (1), 3'-O-methylorobol (2), acactin 7-rutinoside (3), sedelolactone (4), 4-methoxyphenol (5), 4-hydroxyaldehyde (6), 4-hydoxyaldehyde (7), 4-hydroxy-3-methoxybenzoic acid (8), and ferulic acid (9) from the methanolic extract of aerial parts of Eclipta prostrata L.. Among the isolated compounds, luteolin (1) significantly inhibited the proliferation of HSCs in dose- and time-dependent manners. Antifibrotic activity of E. prostrata and its phenolic compounds might provide potential therapeutical choice in the treatment of hepatic fibrosis.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1074-1079
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• 2006

As part of our research on phytochemicals that exert protective effects against diseases related to reactive nitrogen species, we have evaluated the scavenging activity of the yellow leaves of Ginkgo biloba on $ONOO^{-}$. The methanol extract and ethyl acetate fraction obtained from yellow leaves of G. biloba evidenced a marked scavenging activity on authentic $ONOO^{-}$. Repeated column chromatography of the active ethyl acetate soluble fraction on silica gel, Sephadex LH-20, and RP-18, resulted in the purification of 15 known compounds, including sciadopitysin (1), ginkgolide B (2), bilobalide (3), isoginkgetin (4), kaempferol (5), luteolin (6), protocatechuic acid (7), bilobetin (8), amentoflavone (9), ${\beta}-sitosterol$ glucopyranoside (10), kaempferol 3-O-rhamnopyranoside (11), kaempferol 3-O-glucopyranoside (12), kaempferol $3-O-[{6^{'}-O-p-coumaroyl-{\beta}-D-glucopyranosyl(1{\rightarrow}2)-{\alpha}-L-rhamnopyranoside]$ (13), kaempferol 3-O-rutinoside (14), and 6-hydroxykynurenic acid (15). Among the compounds isolated, flavonoids (5, 6 and 11-14), protocatechuic acid (7), and 6-hydroxykynurenic acid (15) all exhibited marked scavenging activities on authentic $ONOO^{-}$. The $IC_{50}$ values of 5-7, 11-14 and 15 were as follows: $2.86{\pm}0.70,\;2.30{\pm}0.04,\;2.85{\pm}0.10,\;5.60{\pm}0.47,\;4.16{\pm}1.65,\;2.47{\pm}0.15,\;3.02{\pm}0.48,\;and\;6.24{\pm}0.27\;{\mu}M$, respectively. DL-Penicillamine ($IC_{50}=4.98{\pm}0.27\;{\mu}M$) was utilized as a positive control. However, the other compounds (1-4, 8-10) exerted no effects against $ONOO^{-}$.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.83-86
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• 2008

Four compounds, luteolin(1), quercetin(2) astragalin(3), rutin(4), were isolated from the methanol extract of the all part of Polytrichum commune. on the basis of chemical and spectroscopic evidence. These compounds have not been isolated from this plant.