• Korean Journal of Pharmacognosy
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• v.50 no.4
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• pp.245-252
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• 2019

This study was initially explored to procure biomaterials capable of inhibiting cancer cell growth from nine Persicaria species (Polygonaceae). The extract of P. nepalensis that was selected from the initial screenings was further fractionated to identify bioactive compounds. The ethyl acetate (EtOAc) fraction was shown to be the most active in the inhibition of cell growth against six cancer cell lines (IC₅₀ value of 3.77-12.87 ㎍/ml). Phytochemical study led to the isolation of two galactolipids of 1,2-di-O-linolenoyl-3-O-β-D-galactospyranosyl-sn-glycerol (1) and 1-O-linolenoyl-3-O-β-D-galactospyranosyl-sn-glycerol (2) from the hexane fraction and three phenylpropanoyl sucroses of lapathoside A (3), vanicoside B (4) and lapathoside C (5) from the EtOAc fraction. These isolated compounds have not been reported from this plant. Compounds 3 and 4 exhibited the effective growth inhibition against a panel of cancer cell lines (IC₅₀ value of 6.90-18.09 μM). In addition, the anti-inflammatory activity was evaluated to determine lipopolysaccharide (LPS)-induced nitric oxide (NO) formation in RAW264.7 mouse macrophage cells. The EtOAc fraction (IC₅₀; 34.14 ㎍/ml) and its constituents, 3 (8.55 μM) and 4 (7.83 μM) were shown to be effective in the inhibition of LPS-induced NO production. Therefore, compounds 3 and 4 were considered to be active constituents for anti-inflammatory and antitumor activity from P. nepalensis.

• Korean Journal of Medicinal Crop Science
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• v.14 no.5
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• pp.267-272
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• 2006

Phytochemical study on the EtOAc fraction from the MeOH extract of the leaves of Cedrela sinensis led to the isolation of five known phenolic compounds (1-5), whose structures were identified as (+)-catechin (1), $kaempferol-3-0-{\alpha}- L-rhamnopyranoside$ (2), quercetin (3), $quercetin-3-O-{\alpha}-L-rhamnopyranoside$ (4), and $quercetin-3-O-{\beta}-D-glucopyranoside$ (5), respectively, by comparing their spectral $(uv,\;JR,\;IH\;and\;^{13}C-NMR,\;and\;ESI-MS)$ and physicochemical data with those reported in the literature. Among the isolated compounds (1-5), compounds 1 and 3-5 exhibited significant DPPH radical scavenging effects with $IC{_50}$ values ranging from $21.3{\pm}1.4\;to\;38.1{\pm}3.2 {\mu}M$ as well as superoxide anion radical scavenging effects with $IC{_50}$ values ranging from $9.4{\pm}0.7\;to\;21.2{\pm}3.6 {\mu}M$. Furthermore, compounds 1 and 3-5 also exhibited considerable inhibitory effects on LDL peroxidation induced by either $CU^{2+}$ or AAPH with $IC{_50}$ values ranging from $1.4{\pm}0.4\;to\;11.9{\pm}1.4\;{\mu}M$. These results indicated that flavonoids are the major constituents of C. sinensis and considered to be antioxidant principles of this plant.

• Korean Journal of Pharmacognosy
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• v.47 no.1
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• pp.1-6
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• 2016

Phytochemical investigation of the twigs of Corylopsis coreana afforded 10 phenolic compounds, bergenin (1), 6'-O-galloylbergenin (2), 3'-O-galloylbergenin (3), (-)-catechin (4), (-)-epicatechin (5), (-)-epicatechin-3-O-galloyl ester (6), 4-methoxy-3,-5-dihydroxybenzoic acid (7), gallic acid (8), 2,4,6-trimethoxyphenol-1-O-${\beta}-\small{D}$-glucopyranoside (9), and 2,4,6-trimethoxyphenol-1-O-${\beta}-\small{D}$-(6-O-galloyl)-glucopyranoside (10). Their structures were characterized by spectroscopic data and identified by comparing these data with those in the literatures. The compounds 3, 9 and 10 were isolated for the first time from this source. All the isolates (1-10) were tested for their cytotoxic activity against A549, SK-OV-3, SK-MEL-2, and HCT15 cell lines in vitro using the SRB bioassay. The compounds 5, 7 and 8 exhibited selective cytotoxic activity against SK-MEL-2 cell line.

• Natural Product Sciences
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• v.22 no.2
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• pp.111-116
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• 2016

Phytochemical investigation of the stems of Pueraria lobata (Wild) Ohwi (Leguminosae), led to the isolation of eighteen known compounds: ${\beta}$-amyrone (1), (+)-pinoresinol (2), (+)-syringaresinol (3) $(+)-syringaresinol-O-{\beta}-{\small{D}}-glucoside$ (4), (+)-lariciresinol (5), (-)-tuberosin (6), naringenin (7), liquiritigenin (8), isoliquiritigenin (9) genistein (10), daidzein (11) daidzin (12) daidzein 4',7-diglucoside (13) 2,4,4'-trihydroxy deoxybenzoin (14), S-(+)-1-hydroxy-3-(4-hydroxyphenyl)-1-(4-hydroxy-2-methoxy-phenyl)propan-2-one (15), methyl $2-O-{\beta}-{\small{D}}-glucopyranosylbenzoate$ (16), pyromeconic acid $3-O-{\beta}-{\small{D}}-glucopyranoside$ 6'- (O-4''-hydroxy-3-methoxybenzoate) (17), and allantion (18). The chemical structures of these compounds were elucidated from spectroscopic data and by comparison of those data with previously published results. The effects of isolated compounds on mushroom tyrosinase enzymatic activity were screened. The results indicated that, chloroform extract of P. lobata stems turned out to be having tyrosinase inhibitory effect, and only compounds 5, 8, 9, and 11 showed enzyme inhibitory activity, with $IC_{50}$ values of $21.49{\pm}4.44$, $25.24{\pm}6.79$, $4.85{\pm}2.29$, and $17.50{\pm}1.29{\mu}M$, respectively, in comparison with these of positive control, kojic acid ($IC_{50}\;12.28{\pm}2.72{\mu}M$). The results suggest that P. lobata stems extract as well as its chemical components may represent as potential candidates for tyrosinase inhibitors.

• Genomics & Informatics
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• v.18 no.4
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• pp.43.1-43.13
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• 2020

The coronavirus disease 2019 is a contagious disease and had caused havoc throughout the world by creating widespread mortality and morbidity. The unavailability of vaccines and proper antiviral drugs encourages the researchers to identify potential antiviral drugs to be used against the virus. The presence of RNA binding domain in the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) could be a potential drug target, which serves multiple critical functions during the viral life cycle, especially the viral replication. Since vaccine development might take some time, the identification of a drug compound targeting viral replication might offer a solution for treatment. The study analyzed the phylogenetic relationship of N protein sequence divergence with other 49 coronavirus species and also identified the conserved regions according to protein families through conserved domain search. Good structural binding affinities of a few natural and/or synthetic phytocompounds or drugs against N protein were determined using the molecular docking approaches. The analyzed compounds presented the higher numbers of hydrogen bonds of selected chemicals supporting the drug-ability of these compounds. Among them, the established antiviral drug glycyrrhizic acid and the phytochemical theaflavin can be considered as possible drug compounds against target N protein of SARS-CoV-2 as they showed lower binding affinities. The findings of this study might lead to the development of a drug for the SARS-CoV-2 mediated disease and offer solution to treatment of SARS-CoV-2 infection.

• Natural Product Sciences
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• v.24 no.4
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• pp.235-240
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• 2018

Betula platyphylla var. japonica (Betulaceae), also known as Asian white birch, is an endemic medicinal tree, the bark of which has been used in Chinese traditional medicine for the treatment of various inflammatory diseases. In our continuing search for bioactive compounds from Korean natural resources, a phytochemical investigation of the bark of B. platyphylla var. japonica led to the isolation of 7-oxo-${\beta}$-sitosterol (1) and soyacerebroside I (2) from its ethanol extract as main components by liquid chromatography (LC)/mass spectrometry (MS)-based analysis. The structures of isolates were identified by comparison of $^1H$ and $^{13}C$ nuclear magnetic resonance spectroscopic data and physical data with the previously reported values and LC/MS analyses. To the best of our knowledge, this is the first study to demonstrate that the isolated compounds, 7-oxo-${\beta}$-sitosterol and soyacerebroside I, were isolated in B. platyphylla var. japonica. We examined the effects of the isolates on the regulation of adipocytes and osteoblast differentiation. These isolates (1 and 2) produced fewer lipid droplets compared to the untreated negative control in Oil Red O staining of the mouse mesenchymal stem cell line without altering the amount of alkaline phosphatase staining. The results demonstrated that both compounds showed marginal inhibitory effects on adipocyte differentiation but did not affect osteoblast differentiation.

• Natural Product Sciences
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• v.13 no.3
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• pp.186-189
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• 2007

The aerial parts of Verbascum sinaiticum Benth. (Scrophulariaceae) yielded two iridoids that were idenified as ajugol 3 and aucubin 4. Also, investigation of the flavonoid constituents revealed the isolation and identification of luteolin 1 and chrysoeriol-7-glucoside 2. All the isolated compounds were identifid by spectroscopicmethods (UV, MS, $^{1}H-NMR$ and $^{13}C-NMR$) and in comparison with the literature data. Both alcohol and methylene chloride/methanol extracts (1 : 1) exhibited a hepatoprotective effect by $CCl_{4}challenge$ test.

• Archives of Pharmacal Research
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• v.26 no.7
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• pp.521-525
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• 2003

Phytochemical works on the aerial parts of Aster oharai (Compositae) led to the isolation of a new sesquiterpene hydroperoxide, 7$\alpha$-hydroperoxy-3, 11-eudesmadiene (2) and seven known compounds, teucdiol B (1), $\alpha$-spinasterol (3), oleanolic acid (4), $\alpha$-spinasterol 3-Ο-$\beta$-D-glucopyranoside (5), methyl 3,5-di-Ο-caffeoyl quinate (6), 3,5-di-Ο-caffeoylquinic acid (7), 3,4-di-Ο-caffeoylquinic acid (8). The chemical structures of 1-8 were established by chemical and spectroscopic methods. Compound 2 showed cytotoxicity against cultured human tumor cell lines in vitro, SK-OV-3 (ovarian), SK-MEL-2 (skin melanoma), and HCT15 (colon) with $ED_{50}$ values ranging from 3.86-17.21 $\mu$g/mL.

• Natural Product Sciences
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• v.14 no.2
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• pp.131-137
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• 2008

From the 70% EtOH extract of the roots of Astragalus membranaceus (Leguminosae), eleven flavonoid derivatives and a lignan, were isolated and identified as liquiritigenin (1), daidzein (2), formononetin (3), sophorophenolone (4), calycosin (5), methylnissolin (6), isomucronulatol (7), isomucronulatol 7-O-glucoside (8), methylnissolin 3-O-glucoside (9), calycosin 7-O-glucoside (10), (+)-syringaresinol O-${\beta}$-D-glucoside (11), and isomucronulatol 7,2'-di-O-glucoside (12), by spectroscopic methods. This is the second report of the isoflavonoid derivatives sophorophenolone (4) and isomucronulatol 7,2'-di-O-glucoside (12) from a natural source, as well as the first report of compounds liquiritigenin (1), daidzein (2) and (+)-syringaresinol O-${\beta}$-D-glucoside (11) from the species A. membranaceus.

• Natural Product Sciences
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• v.21 no.2
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• pp.82-86
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• 2015

Phytochemical constituents were isolated from the fruits of Acanthopanax chiisanensis by repeated column chromatography. Their structures were identified as $\beta$-sitosterol (1), daucosterol (2), sesamin (3), chiisanogenin (4), and $22\alpha$-hydroxy chiisanogenin (5) by spectroscopic analysis (MS, ¹H-, and ¹³C-NMR). Compounds 1 - 5 were isolated for the first time from the fruits of A. chiisanensis.