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1.
Chem Biodivers ; 19(3): e202100897, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35083849

RESUMO

A new lignan (4,4',5'-trihydroxy-5,3'-dimethoxy-3-O-9',2-(7'R)-lignan, 1) and eight C(6)-oxygenated flavonoids (2-9), including a newly identified flavonoid (7,3',4'-trihydroxy-3,5,6-trimethoxyflavone, 2), were isolated from the inflorescence of Ambrosia artemisiifolia L. The structures of these isolates were determined using extensive spectroscopic analyses and comparison with data previously reported in the literature. The absolute configuration of compound 1 was established using electronic circular dichroism (ECD) spectrum. All the flavonoids (2-9) showed inhibitory effects on LPS-induced NO production in RAW264.7 cells, with the inhibition rate ranging from 24.51 % to 69.82 % at 50 µM. The in vitro cytotoxicity study showed that compounds 3-8 have a 60 % inhibition rate against SMMC-7721 at a concentration of 40 µM, while compounds 5 and 8 also exhibited inhibitory activity against HL-60 at 40 µM with the inhibition rate of 83.36 % and 52.01 %, respectively.


Assuntos
Ambrosia , Lignanas , Ambrosia/química , Flavonoides/química , Flavonoides/farmacologia , Inflorescência , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular
2.
Molecules ; 25(24)2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33419270

RESUMO

Five new cyclic diarylheptanoids (platycary A-E, compounds 1-5) and three previously identified analogues (i.e., phttyearynol (compound 6), myricatomentogenin (compound 7), and juglanin D (compound 8)) were isolated from the stem bark of Platycarya strobilacea. The structures of these compounds were determined using NMR, HRESIMS, and electronic circular dichroism (ECD) data. The cytotoxicity of compounds 1-5 and their ability to inhibit nitric oxide (NO) production, as well as protect against the corticosterone-induced apoptosis of Pheochromocytoma (PC12) cells, were evaluated in vitro using the appropriate bioassays. Compounds 1 and 2 significantly inhibited the corticosterone-induced apoptosis of PC12 cells at a concentration of 20 µΜ.


Assuntos
Diarileptanoides/farmacologia , Juglandaceae/química , Estrutura Molecular , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Diarileptanoides/isolamento & purificação , Humanos , Neoplasias/patologia , Óxido Nítrico/metabolismo , Ratos
3.
Nat Prod Res ; 34(14): 1977-1983, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30732479

RESUMO

A new derivative of epicatechin glucopyranoside, (2R,3R)-3,7,4'-trihydroxy-5,3'-dimethoxyflavan 7-O-ß-d-glucopyranoside (1), together with three mononuclear phenolic acid esters, methyl orsellinate (2), ethyl orsellinate (3) and methyl ß-orcinolcarboxylate (4) were isolated from the bark of Styrax suberifolius. The structures of 1-4 were determined on the basis of extensive analysis of NMR and MS spectra combined with chemical hydrolysis. The antifungal activities of the isolated compounds against three plant pathogenic fungi, Alternaria solani, Fusarium oxysporum and Phomopsis cytospore were evaluated using radial growth inhibition assay. Compounds 2, 3 and 4 exerted selective inhibitory activities against the tested fungi. Among of them, methyl ß-orcinolcarboxylate (4) exhibited obvious inhibitory effect against P. cytospore, with an inhibition rate of 86.72% at 100 µg/ml.


Assuntos
Antifúngicos/isolamento & purificação , Catequina/isolamento & purificação , Styrax/química , Alternaria/efeitos dos fármacos , Antifúngicos/farmacologia , Catequina/química , Catequina/farmacologia , Fungos/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Extratos Vegetais/química
4.
Int J Cancer ; 146(6): 1754-1763, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31456215

RESUMO

To explore whether plasma circular RNAs (circRNAs) can diagnose hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), microarray and qPCR were used to identify plasma circRNAs that were increased in HBV-related HCC patients compared to controls (including healthy controls, chronic hepatitis B and HBV-related liver cirrhosis). A logistic regression model was constructed using a training set (n = 313) and then validated using another two independent sets (n = 306 and 526, respectively). Area under the receiver operating characteristic curve (AUC) was used to evaluate diagnostic accuracy. We identified a plasma circRNA panel (CircPanel) containing three circRNAs (hsa_circ_0000976, hsa_circ_0007750 and hsa_circ_0139897) that could detect HCC. CircPanel showed a higher accuracy than AFP (alpha-fetoprotein) to distinguish individuals with HCC from controls in all three sets (AUC, 0.863 [95% confidence interval, CI: 0.819-0.907] vs. 0.790 [0.738-0.842], p = 0.036 in training set; 0.843 [0.796-0.890] vs. 0.747 [0.691-0.804], p = 0.011 in validation set 1 and 0.864 [0.830-0.898] vs. 0.769 [0.728-0.810], p < 0.001 in validation set 2). CircPanel also performed well in detecting Small-HCC (solitary, ≤3 cm), AFP-negative HCC and AFP-negative Small-HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Vírus da Hepatite B , Hepatite B/complicações , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/etiologia , RNA Circular/sangue , Biomarcadores Tumorais , Feminino , Perfilação da Expressão Gênica , Hepatite B/virologia , Humanos , Masculino , Reação em Cadeia da Polimerase , Curva ROC , Reprodutibilidade dos Testes
5.
Mycobiology ; 43(4): 435-43, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26839503

RESUMO

Sixty-one endophytic fungus strains with different colony morphologies were isolated from the leaves, stems and roots of Tephrosia purpurea with colonization rates of 66.95%, 37.50%, and 26.92%, respectively. Based on internal transcribed spacer sequence analysis, 61 isolates were classified into 16 genera belonging to 3 classes under the phylum Ascomycota. Of the 61 isolates, 6 (9.84%) exhibited antifungal activity against one or more indicator plant pathogenic fungi according to the dual culture test. Isolate TPL25 had the broadest antifungal spectrum of activity, and isolate TPL35 was active against 5 plant pathogenic fungi. Furthermore, culture filtrates of TPL25 and TPL35 exhibited greater than 80% growth inhibition against Sclerotinia sclerotiorum. We conclude that the endophytic fungal strains TPL25 and TPL35 are promising sources of bioactive compounds.

6.
J Asian Nat Prod Res ; 16(2): 135-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24320876

RESUMO

A new intact resin glycoside (3) and two glycosidic acids (1 and 2), all having a common trisaccharide moiety and (11S)-hydroxytetradecanoic acid or (3S,11S)-dihydroxytetradecanoic acid as the aglycone, were obtained from the roots of Porana duclouxii. Their structures were elucidated by spectroscopic analyses and chemical correlations. These compounds represent the first examples of resin glycosides from the genus Porana.


Assuntos
Convolvulaceae/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Glicosídeos/isolamento & purificação , Resinas Vegetais/química , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química
7.
J Asian Nat Prod Res ; 14(6): 555-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22587796

RESUMO

Further investigation on the stems of Artocarpus nitidus subsp. lingnanensis led to the isolation and characterization of a new flavan-3-ol, named artoflavanocoumarin, along with three known compounds (+)-catechin, (+)-afzelechin 3-O-α-L-rhamnoside, and (+)-catechin 3-O-α-L-rhamnoside. Their structures were elucidated on the basis of spectroscopic data.


Assuntos
Artocarpus/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonoides/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Flavonoides/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Caules de Planta/química , Estereoisomerismo
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