• Archives of Pharmacal Research
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• v.25 no.3
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• pp.313-319
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• 2002

A total of eight flavonoids (1-8), including a novel $quercetin-7-o-(6"-o-acetyl)-{\beta}-D-glucopyranoside$ (6) and seven known flavonoids, luteolin (1), quercetin (2), luteolin $7-o-{\beta}-D-glucopyranoside$ (3), $luteolin-7-o-(6"-Ο-acetyl)-{\beta}-D-glucopyranoside$ (4) quercetin $7-o-{\beta}-D-glucopyranoside$ (5), acacetin 7-o-{\beta}-D-glucuronide (7) and apigenin-6-C-{\beta}-D-glucopyrano $syl-8-C-{\beta}-D-glucopyranoside$ (8), have been isolated from the leaves of the safflower (Carthamus tinctorius L.) and identified on the basis of spectroscopic and chemical studies. The antioxidative activity of these flavonoids was evaluated against 2-deoxyribose degradation and rat liver microsomal lipid peroxidation induced by hydroxyl radicals generated via a Fenton-type reaction. Among these flavonoids, luteolin-acetyl-glucoside (4) and quercetin-acetyl-glucoside (6) showed potent antioxidative activities against 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. Luteolin (1), quercetin (2), and their corresponding glycosides (3 & 5) also exhibited strong antioxidative activity, while acacetin glucuronide (7) and apigenin-6,8-di-C-glucoside (8) were relatively less active.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1031-1036
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• 2005

[ $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ ] (1) was isolated from an ethyl acetate extract of the root bark from Lycium chinense Miller, and its structure was determined using 1D and 2D NMR spectroscopy including DEPT, HMQC, and HMBC. $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ exhibited potent antimicrobial activity against antibiotic-resistant bacterial strains, methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients, and human pathogenic fungi without having any hemolytic effect on human erythrocytes. In particular, compound 1 induced the accumulation of intracellular trehalose on C. albicans as stress response to the drug, and disrupted the dimorphic transition that forms pseudo-hyphae caused by the pathogenesis. This indicates that $(+)-Lyoniresinol-3{\alpha}-O-\beta-D-glucopyranoside$ has excellent potential as a lead compound for the development of antibiotic agents.

• YAKHAK HOEJI
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• v.59 no.3
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• pp.120-126
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• 2015

Akebiae caulis have been used in folk medicines for diuretic, menstrual pain, and diuretic pain. It has been also resolved nephritis and cystitis. In this study, we isolated three phenolic compounds from 70% methanol extract using the open column chromatography. These isolated compounds which were 2-(3,4-dihydroxyphenyl)-ethyl-${\beta}$-D-glucopyranoside, 5-O-caffeoylquinic acid, and syringoylglycerol 2-O-${\beta}$-D-glucoside were determined by physico-chemical apparatus. Furthermore, we conducted DPPH and ABTS assay in order to screen the antioxidant activity of isolated three compounds. Also, we developed a rapidly HPLC-UV analysis method of two phenolic compounds (2-(3,4-dihydroxyphenyl)-ethyl-${\beta}$-D-glucopyranoside, 5-O-caffeoylquinic acid) for evaluating the Akebiae Caulis collected 30 samples from different regions. From the experiments, all three isolated compounds showed the significant antioxidant activity. We suggested that the content criteria of marker compounds were shown by a simple and rapid HPLC-UV method. The contents respectively were 0.009% (2-(3,4-dihydroxyphenyl)-ethyl-${\beta}$-D-glucopyranoside) and 0.036% (5-O-caffeoylquinic acid).

• Korean Journal of Pharmacognosy
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• v.44 no.1
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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.

• Natural Product Sciences
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• v.18 no.3
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• pp.190-194
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• 2012

The effects of methanol extract of the leaves of Brassica juncea and its major component, isorhamnetin 3-O-${\beta}$-D-glucopyranoside on hepatic alcohol metabolizing enzymes were investigated. The methanol extract and isorhamnetin 3-O-${\beta}$-D-glucopyranoside supplementations increased the activities of microsomal ethanol oxidizing system and aldehyde dehydrogenase in a dose-dependent manner, and had mild effects on the activities of alcohol dehydrogenase and catalase. Isorhamnetin 3-O-${\beta}$-D-glucopyranoside alleviated the adverse effect of ethanol ingestion by enhancing the activities of alcohol oxidizing emzymes, microsomal ethanol oxidizing system and aldehyde dehydrogenase.

• Natural Product Sciences
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• v.24 no.4
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• pp.259-265
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• 2018

The three flavone glycosides, 4'-O-methylisoscutellarein 7-O-(6'''-O-acetyl)-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (1), isoscutellarein 7-O-(6'''-O-acetyl)-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (3), and isoscutellarein 7-O-${\beta}$-D-allopyranosyl(1${\rightarrow}$2)-${\beta}$-D-glucopyranoside (4) in addition to a flavonol glycoside, kaempferol 3-O-${\beta}$-D-glucopyranoside (astragalin, 2), were isolated from Stachys japonica (Lamiaceae). In cholinesterase inhibition assay, compound 1 significantly inhibited aceylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities ($IC_{50}s$, $39.94{\mu}g/ml$ for AChE and $86.98{\mu}g/ml$ for BChE). The content of isolated compounds were evaluated in this plant extract by HPLC analysis. Our experimental results suggest that the flavonoid glycosides of S. japonica could prevent the memory impairment of Alzheimer's disease.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.98-102
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• 2005

The MeOH extracts obtained from whole plant of Trigonotis peduncularis Benth. were solvent fractionated using EtOAc, n-BuOH and water, successively. The EtOAc and n-BuOH fractions gave four flavonol glycosides through application of silica gel and octadecyl silica gel (ODS) column chromatographies. The chemical structures of the flavonol glycosides were determined by the interpretation of several spectral data including 2D-NMR as $kaempferol-3-O-{\beta}-{D}-glucopyranoside\;(astragalin,\;1),\;kaempferol-3-O-{\alpha}-{L}-rhamnopyranosyl\;(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside\;(nicotiflorin,\;2),\;quercetin-3-O-{\alpha}-{L}-rhamnopyranosyl(1{\rightarrow}6)-{\beta}-{D}-glucopyranoside\;(rutin,\;3),\;quercetin-3-O-{\beta}-{D}-glucopyranoside\;(isoquercitrin,\;4)$. The flavonoids have been first isolated from this plant. Nicotiflorin $(100\;{\mu}g/ml)$ showed $68.3{\pm}1.2%$ of the inhibitory effect on hACAT1(human Acyl CoA: cholesterol transferase 1) activity.

• Korean Journal of Pharmacognosy
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• v.34 no.2 s.133
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• pp.119-122
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• 2003

From the whole plants of Bothriospermum tenellum (Boraginaceae) four phenolic compounds, kaempferol, caffeic acid, $kaempferol-3-O-{\beta}-D-glucopyranoside$ and $kaempferol-3-O-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}6)-{\beta}-D-glucopyranoside$ have been isolated and characterized by physicochemical and spectral means.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.854-857
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• 2007

In this study, the crude methanol extract of mulberry leaves was fractionated with chloroform, ethyl acetate, n-butanol, and water, successively. The antioxidant activities of the fractions were examined with the 2-deoxyribose oxidation and linoleic acid peroxidation methods. The ethyl acetate fraction showed the strongest antioxidant activity. From it we isolated chlorogenic acid, caffeic acid, quercetin $3-O-{\beta}-D-glucopyranoside$, and kaempferol $3-O-{\beta}-D-glucopyranoside$ with preparatory octadecyl silane-high performance liquid chromatography (ODS-HPLC), and identified the compounds by nuclear magnetic resonance (NMR) and fast atom bombardment mass (FAB-MS) analyses. Overall, quercetin $3-O-{\beta}-D-glucopyranoside$ showed the strongest antioxidant activity by both the 2-deoxyribose oxidation and rat liver microsome peroxidation methods.

• Natural Product Sciences
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• v.16 no.4
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• pp.217-222
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• 2010

A phytochemical investigation of the ethanolic extract of Erythrina caffra flowers from an Egyptian origin yielded three C-flavonoidal glycosides; 5,7,4'-trihydroxyflavone-8-C-$\beta$-D-glucopyranoside (vitexin) (1), 5,7,4'-trihydroxyflavone-6-C-$\beta$-D-glucopyranosyl-(1 $\rightarrow$ 2)-$\beta$-D-glucopyranoside (isovitexin-2"-$\beta$-D-glucopyranoside) (2), 5, 7, 4'-trihydroxyflavone-6, 8-di-C-$\beta$-D-glucopyranoside (vicenin-2) (3) and one O-flavonoidal glycoside; kaempferol-3-O-$\beta$-D.glucopyranosyl) (1 $\rightarrow$ 2)-$\beta$-D-glucopyranoside (4). The structures of the isolated compounds (1 - 4) were elucidated using different spectral techniques (UV, 1D and 2D NMR and HRESIMS). This is the first report for the isolation of flavonoidal glycosides from Erythrina caffra. The antibacterial, antifungal, antimalarial, and antileishmanial activities of the isolates were evaluated. In addition, the cytotoxic activity of the ethanolic extract and the main fractions were tested using brine shrimp bioassay.