• Journal of the Korean Wood Science and Technology
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• v.31 no.3
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• pp.70-76
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• 2003

Five isoflavonoids, biochanin A-7-O-β-D-xylopyranosyl-(1⟶6)-β-D-gluco- pyranoside (1), (-)-maackiain (2), calycosin (3), trifolirhizin (4) and genistein (5), were tested for antifungal activity against nine fungi. These compounds were isolated from the wood (compound 1 and 2) and from the bark (compound 3, 4 and 5) of S. japonica. According to the results of antifungal activity test, (-)-maackiain was evaluated as the best antifungal compound among the isolated compounds. In this regard, it could be mentioned that high antifungal activity of S. japonica wood extracts was originated from (-)-maackiain.

• Korean Journal of Pharmacognosy
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• v.53 no.3
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• pp.133-137
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• 2022

Four known triterpenoids and one sterol glycoside were isolated from Viburnum opulus var. clavescens for. sterile flowers. By the spectral data analysis, we determined to be the structures of isolated compounds as 𝛼-amyrin (1), ursolic aldehyde (2), maslinic acid (3), ursolic acid (4) and 𝛽-sitosterol-3-O-glucoside (5). Among the isolated compounds, we revised ¹³C-NMR chemical shifts of ursolic aldehyde (2) using DEPT and HMBC spectra analysis. 𝛼-Amyrin (1), ursolic aldehyde (2), maslinic acid (3) and 𝛽-sitosterol-3-O-glucoside (5) were isolated for the first time from this plant.

• Korean Journal of Medicinal Crop Science
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• v.19 no.4
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• pp.251-256
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• 2011

The leaves of Hippophae rhamnoides were extracted with methanol and then further fractioned with hexane, ethyl acetate, butanol and water in order to investigate biological activity. Two flavonol glycosides were isolated and identified from ethyl acetate soluble fraction, which showed the strongest antioxidant activity ($RC_{50}$ = 4.33 ${\mu}g/ml$). Isolated two compounds have shown strong free radical scavenging activity. Especially, quercetin 3-O-glucoside ($RC_{50}$ = 2.60 ${\mu}g/ml$) was more active than ${\alpha}$-tocopherol ($RC_{50}$ = 4.67 ${\mu}g/ml$). Total phenol and flavonoid contents were the highest to 4.17 and 1.14 mg/ml in the ethyl acetate soluble fraction. In addition, ethyl acetate soluble fraction was shown to the strongest ${\alpha}$-glucosidase inhibitory activity ($IC_{50}$ = 137.88 ${\mu}g/ml$) among the fractions. The results suggest that leaves of H. rhamnoides could be a potential source of natural antioxidant.

• Applied Biological Chemistry
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• v.39 no.4
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• pp.320-326
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• 1996

Seven antioxidative flavonoids were isolated from Jindalrae flowers (Rhododendron mnonulatum Turcz.), an edible plant in Korea. These compounds were identified as afzelin, ampelopsin, catechin, myricetin, myricitrin, quercetin and quercitrin on the basis of IR, UV, FAB-MS, $^1H\;NMR,\;and\;^{13}C\;NMR$ data. These compounds were consisted of two flavonols, three flavonol glycosides, a flavane, and a dihydroflavonol. The flavonol glycosides (14.4 g) present in th ethyl ether and ethyl acetate fractions comprised up to 82% of their total flavonoid amount (17.6 g) finally recovered by means of polyamide C-200 column chromatography, preparative TLC, recrystallization, and Sephadex LH-20 column chromatography. The antioxidant activities were measured in an ethanol solution of linoleic acid in the presence of ferric thiocyanate. The antioxidant efficiency increased in the order of afzrlin<$\alpha-tocopherol$

• 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.

• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.296-298
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• 2007

Two lignan glycoside compounds were isolated from the twigs of Vaccinium oldhami (Ericaceae) through repeated column chromatography. Their chemical structures were elucidated as lyoniside and ssioriside, respectively, by spectroscopic analysis.

• Bulletin of the Korean Chemical Society
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• v.30 no.5
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• pp.1035-1038
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• 2009

Phytochemical investigation of the methanolic extract of Diospyros kaki leaves led to the isolation of osmanthuside H (1) and a new phenol glycoside, named gamnamoside [4-(3-hydroxypropyl)-2-methoxyphenol $\beta$-D-apiofuranosyl( 1 $\rightarrow$ 6)$\beta$-D-glucopyranoside] (2) along with (-) catechin (3) through a series of reversed phase column chromatography and preparative C18 HPLC. The structures of the isolates were determined by spectroscopic methods including IR, UV, HRTOFMS, and 2D NMR. Compounds 1, 2, and 3, showed good inhibitory activities ($IC_{50}$) of 175.4, 94.4, and 126.6 ${\mu}g/mL$ respectively, whereas a reversible ADH inhibitor, 4-methylpyrazole, showed the $IC_{50}$ of 326.6 ${\mu}g/mL$ against alcohol dehydrogenase (ADH).

• 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.

• Korean Journal of Pharmacognosy
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• v.51 no.2
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• pp.93-99
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• 2020

This study was performed to find anti-inflammatory or antitumor compounds from the polar fraction obtained from the extract of Clinopodium chinense var. shibetchense (H. Lev) Koidz (Labiatae). Chromatography of the BuOH fraction yielded two flavonoid glycosides (compounds 1 and 2) and two saponins (compounds 3 and 4). On the basis of spectroscopic data, compounds 1 and 2 were identified to be ponciretin 7-O-α-L-rhamnopyranosyl-(1→6)-α-D-glucopyranoside (neoponcirin) and naringenin 7-O-α-L-rhamnopyranosyl-(1→6)-α-D-glucopyranoside (isonaringin). Compounds 3 and 4 were identified to be 3-O-{β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-fucopyranosyl}-saikogenin F (buddlejasaponin IV) and 3-O-{β-D-glucopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-fucopyranosyl}-21β-hydroxysaikogenin F (clinoposaponin XV). In addition, ursolic acid (5) was isolated and identified from the CHCl₃ fraction. Inducible nitric oxide synthase (iNOS) assay and sulforhodamine B (SRB) assay were performed to lead a potential anti-inflammatory or anti-tumor compounds from C. chinense var. shibetchense. Of the four compounds (1 - 4), compound 3 considerably inhibited cancer cell growth and NO production (IC₅₀s, 5.59 μM in iNOS assay and 6.62 - 14.88 μM in SRB assay).

• Natural Product Sciences
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• v.11 no.3
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• pp.119-122
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• 2005

In the course of searching for hepatoprotective agents from natural products, four compounds were isolated from the MeOH extract of Sanguisorbae Radix, as guided by their DPPH free radical scavenging activity. The structures were determined as 4,5-dimethoxy-3-hydroxybenzoic acid methyl ester (1), (+)-gallocatechin (2), methyl $6-O-galloyl-{\beta}-D-glucopyranoside$ (3), and pomolic acid $3-O-[{\alpha}-L-arabinopyranoside]-28-O-[{\beta}-D-glucopyranosyl]$ ester (ziyu-glycoside I) (4). Compounds 2 and 3 showed significant DPPH free radical scavenging effects, exhibiting $IC_{50}$ values of 11.4 and $13.0\;{\mu}M$, respectively. L-Ascorbic acid was used as a positive control and exhibited the $IC_{50}$ value of $50.3\;{\mu}M$. In evaluation of the hepatoprotective activity of the isolated compounds on drug-induced cytotoxicity, compound 2 showed the significant hepatoprotective effect with the $EC_{50}$ value of $91.84\;{\pm}\;11.0\;{\mu}M$ on tacrine-induced cytotoxicity in Hep G2 cells, while silybin, a positive control, exhibited $EC_{50}$ value of $122.4\;{\pm}\;12.5\;{\mu}M$.