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1.
J Agric Food Chem ; 68(6): 1555-1562, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31986026

RESUMO

Passiflora edulis Sims (passion fruit) seeds are often discarded as byproducts during juice processing. In fact, the seeds are of considerable commercial value in the food and cosmetics industry because of their rich polyphenols, especially piceatannol. In this study, high-speed countercurrent chromatography (HSCCC) was applied for the separation of stilbene polyphenols from passion fruit seeds. The n-hexane-ethyl acetate-methanol-water (1:2:1:2.8, v/v) was found to be the optimum two-phase solvent for the preparation of two major stilbenes, scirpusin B (8) and piceatannol (9) with purities of 90.2% and 94.8%, respectively. In addition, a continuous semipreparative HPLC was applied to further purify the HSCCC fractions containing minor stilbenes and obtain four new piceatannol derivatives (1-4) along with three known ones (5-7). The structures of these new compounds were determined using spectroscopic methods, including NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and circular dichroism (CD). The isolated compounds were evaluated for α-glucosidase inhibitory activities in vitro. The result suggested that all of them exhibited more significant activity than acarbose, and passiflorinol B (2) had the strongest activity, with a IC50 value of 1.7 µM.


Assuntos
Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Passiflora/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Estilbenos/química , Estilbenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Distribuição Contracorrente , Frutas/química , Sementes/química , alfa-Glucosidases/química
2.
Molecules ; 24(17)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470596

RESUMO

Sequential extraction and purification stages are required to obtain extracts rich in specific polyphenols. However, both separation processes are often optimized independently and the effect of the integrated process on the global recovery of polyphenols has not been fully elucidated yet. We assessed the impact of hot-pressurized liquid extraction (HPLE) conditions (temperature: 90-150 °C; ethanol concentration: 15%-50%) on the global recovery of specific phenolic acids, flavanols, flavonols and stilbenes from Carménère grape pomace in an integrated HPLE/resin purification (RP) process. HPLE of phenolic acids, flavanols and stilbenes were favored when temperature and ethanol concentration increased, except for chlorogenic acid which showed an increment of its Gibbs free energy of solvation at higher ethanol contents. Ethanol concentration significantly impacted the global yield of the integrated HPLE/RP process. The lower the ethanol content of the HPLE extracts, the higher the recovery of phenolic acids, flavanols and stilbenes after RP, except for flavonols which present more polar functional groups. The best specific recovery conditions were 150 °C and ethanol concentrations of 15%, 32.5% and 50% for phenolic acids, flavanols and stilbenes, and flavonols, respectively. At 150 °C and 32.5% of ethanol, the extracts presented the highest total polyphenol content and antioxidant capacity. The integrated HPLE/RP process allows a selective separation of specific polyphenols and eliminates the interfering compounds, ensuring the safety of the extracts at all evaluated conditions.


Assuntos
Flavonóis/isolamento & purificação , Hidroxibenzoatos/isolamento & purificação , Extração Líquido-Líquido/métodos , Polifenóis/isolamento & purificação , Estilbenos/isolamento & purificação , Vitis/química , Ácido Clorogênico/isolamento & purificação , Etanol/química , Temperatura Alta , Extratos Vegetais/química , Pressão , Solventes/química , Termodinâmica
3.
Fitoterapia ; 138: 104350, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473333

RESUMO

Three new bibenzyl derivatives (bletstrins A-C, 1-3), including two bibenzyls that have hydroxyl-substituted chiral centers on the aliphatic bibenzyl bridge, along with eighteen known stilbenoids (4-21) were isolated from the tubers of Bletilla striata. The structures of new compounds were elucidated by the use of 1D/2D NMR spectroscopic data. The absolute configurations of bletitrins A and B were determined by optical rotation value. Compounds 13-16 were isolated from the Orchidaceae for the first time. Most of the isolated compounds were evaluated for their antibacterial activities against three gram-positive bacterial strains and one gram-negative bacterial strain. Compounds 4, 10, 12, 14, 15, 16 and 18 showed potent inhibitory activities, with MICs of (6-52 µg/mL) against S. aureus ATCC 6538.


Assuntos
Antibacterianos/farmacologia , Orchidaceae/química , Tubérculos/química , Estilbenos/farmacologia , Antibacterianos/isolamento & purificação , Bibenzilas/isolamento & purificação , Bibenzilas/farmacologia , China , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Estilbenos/isolamento & purificação
4.
Molecules ; 24(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340570

RESUMO

As a traditional natural medicine for treating many kinds of diseases, Gnetum parvifolium showed apparent inhibition on xanthine oxidase (XO). In this study, ultrafiltration combined with liquid chromatography-mass spectrometry (LC-MS) is used for the screening of XO inhibitors from Gnetum parvifolium. Their antioxidation, XO inhibition, and enzymic kinetic parameters are also determined. Finally, piceatannol (1), rhaponiticin (2), resveratrol (3), and isorhapontigenin (4) are screened out and identified as XO inhibitors from the extract of Gnetum parvifolium. Four inhibitors show better inhibition than allopurinol and good radical scavenging abilities. However, the antioxidant activities are weaker than ascorbic acid. The kinetic parameters illustrate the inhibition mode of XO by piceatannol is competitive type, while the inhibition modes for rhaponiticin, resveratrol and isorhapontigenin are uncompetitive types. In order to evaluate the difference among samples obtained in China, the amounts of four inhibitors and related activities in 20 samples are assessed and analyzed by partial least squares analysis. The results indicate piceatannol contribute the highest coefficients in three kinds of activities. Based on these findings, more comprehensive research on pharmaceutical and biochemical activities of these four XO inhibitors could be conducted in future.


Assuntos
Gnetum/química , Resveratrol/isolamento & purificação , Estilbenos/isolamento & purificação , Xantina Oxidase/antagonistas & inibidores , Alopurinol/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/farmacologia , Ensaios de Triagem em Larga Escala , Cinética , Análise dos Mínimos Quadrados , Picratos/antagonistas & inibidores , Extratos Vegetais/química , Resveratrol/farmacologia , Estilbenos/farmacologia , Ultrafiltração , Xantina Oxidase/metabolismo
5.
Phytochemistry ; 165: 112044, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31202041

RESUMO

Oligostilbenes are polyphenol oligomers derived from resveratrol and are commonly produced by members of the Gnetaceae family, and many researchers have focused on their anti-inflammatory activities. The EtOAc fraction of a Gnetum latifolium extract showed inhibitory activity against neuroinflammation induced by the transfection of Aß1-42 into microglial BV-2 cells. The bioassay-guided isolation of the 70% EtOH extract of this plant resulted in three previously undescribed resveratrol oligostilbenes and ten known stilbene derivatives. The structures of the isolated compounds were established based on extensive NMR spectroscopic analysis. The absolute configurations of the three undescribed compounds were confirmed by comparison with available compounds with known stereochemistry and by ECD calculations and molecular modelling. Latifoliols A and B are the first reported oligostilbenes with a bridged 3-oxabicyclo[3.3.0]octane moiety, and latifoliol C was formed by the condensation of gnemontanin G with oxyresveratrol. Moreover, the hypothetical biogenetic pathway of latifoliols A, B and C was proposed. The potential anti-inflammatory activities of the thirteen isolated compounds were tested by measuring their effect on the secreted NO concentrations induced by transfection with plasmids expressing the Aß1-42 gene in the BV-2 cell line. Interestingly, cis- and trans-shegansu B and latifolol, whose structures contained double bonds, strongly inhibited NO secretion in BV-2 cells, supporting the double binding effect of the stilbene derivative on inhibitory activity.


Assuntos
Gnetum/química , Inflamação/tratamento farmacológico , Folhas de Planta/química , Estilbenos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Inflamação/patologia , Camundongos , Conformação Molecular , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Estilbenos/química , Estilbenos/isolamento & purificação , Relação Estrutura-Atividade
6.
J Agric Food Chem ; 67(24): 6765-6772, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31180676

RESUMO

One unusual resveratrol tetramer, paeonilactiflorol (1), and 14 known compounds (2-15) were isolated from peony seeds ( Paeonia lactiflora) under the guidance of bioassay. Paeonilactiflorol (1) was determined by extensive HRESIMS, UV, IR, 1D and 2D NMR spectroscopic analyses. Most of the stilbenes showed obvious inhibition on PTP1B and α-glucosidase, superior to the monoterpene glycosides. Especially, the stilbene tetramer (1) and trimer (8) exhibited high activity inhibiting both PTP1B with IC50 values of 27.23 and 27.81 µM and α-glucosidase with IC50 values of 13.57 and 14.39 µM. Two trans-dimers (4 and 5) also showed dipeptidyl peptidase-4 (DPPIV) inhibitory activity (55.35% and 61.26%, 500 µM) in addition to PTP1B and α-glucosidase. Enzyme kinetic study indicated that the types of inhibition on PTP1B were noncompetitive for 3 and 5 and mixed for 8 and 10. Quantitative analysis suggested that the stilbene trimers 8 (23.17 ± 0.36 mg/g) and 10 (15.24 ± 0.25 mg/g) were the main contents in peony seeds and should be responsible for the antidiabetic effects. This investigation supports the therapeutic potential of peony seeds in the treatment of diabetes with stilbenes as the active constituents.


Assuntos
Inibidores da Dipeptidil Peptidase IV/química , Inibidores de Glicosídeo Hidrolases/química , Hipoglicemiantes/química , Paeonia/química , Extratos Vegetais/química , Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Estilbenos/química , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Hipoglicemiantes/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Proteína Tirosina Fosfatase não Receptora Tipo 1/química , Sementes/química , Estilbenos/isolamento & purificação , alfa-Glucosidases/química
7.
Chin J Nat Med ; 17(5): 381-386, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31171273

RESUMO

Three new prenylated stilbenes, named as cajanusins A-C (1-3), and one new natural product cajanusin D (4), along with six known derivatives (5-10) were isolated from the leaves of Cajanus cajan. Their structures were fully elucidated by means of extensive spectroscopic methods and comparison with data in the reported literatures. The new compounds of 1 and 2 were evaluated for in vitro cytotoxic activities against a panel of human cancer cell lines.


Assuntos
Antineoplásicos Fitogênicos/química , Cajanus/química , Flavonoides/química , Estilbenos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Flavonoides/isolamento & purificação , Humanos , Estrutura Molecular , Extratos Vegetais/química , Folhas de Planta/química , Estilbenos/isolamento & purificação , Estilbenos/toxicidade
8.
Phytochem Anal ; 30(4): 464-473, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30950123

RESUMO

INTRODUCTION: The Paeonia ostii T. Hong & J. X. Zhang seed shell, characterised by a high content of oligostilbenes, is one of the two most important by-products in the preparation of seed oil. Oligostilbenes are considered characteristic constituents of the genus Paeonia, and can be used in fingerprinting to determine the geographical origin and the quality of raw materials. OBJECTIVE: To develop and optimise a simple and reproducible high-performance liquid chromatography diode array detection (HPLC-DAD) method for the simultaneous determination of seven oligostilbenes in P. ostii seed shell from different geographical areas, and to associate the cultivation area. METHODOLOGY: A validated HPLC method coupled with a DAD detector was performed for the detection and determination of target compounds in the samples. Optimal chromatographic conditions were achieved using an Agilent Zorbax Eclipse SB-AQ-C18 column and a gradient elution with acetonitrile and potassium dihydrogen phosphate solution. RESULTS: The proposed quantitative method showed appropriate accuracy and precision, and was successfully applied to the routine analysis of seven oligostilbenes and the quality evaluation of 50 P. ostii seed shell samples. There were significant differences between the contents of the seven oligostilbenes in different samples (P < 0.01). CONCLUSION: The results demonstrated that the oligostilbenes were main secondary metabolites in the P. ostii seed shells, and the content of seven components in P. ostii seed shells sourced from different cultivation areas in China was different.


Assuntos
Paeonia/química , Óleos Vegetais/química , Estilbenos/química , China , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas , Geografia , Óleos Vegetais/isolamento & purificação , Sementes/química , Estilbenos/isolamento & purificação , Árvores
9.
ACS Appl Mater Interfaces ; 11(19): 17306-17312, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31020832

RESUMO

Bloodstains provide admissible information for crime scene investigators. The ability to resolve latent bloodstains that are commonly found in real scenarios is therefore pivotal to public security. Here, we report a facile approach for invisible bloodstain visualization based on the click reaction between serum albumin and tetraphenylethene maleimide (TPE-MI), an aggregation-induced emission luminogen (AIEgen). Compared to the widely adopted methods based on the harsh catalytic oxidation activity of hemoglobin, this working principle benefits from the specificity of the mild catalyst-free thiol-ene click reaction that improves the reliability and resolution. In addition, the mild conditions preserve DNA information and bloodstain patterns, and the excellent photophysical properties of the AIEgen afford high sensitivity and stability (>1 yr). Such an excellent performance cannot be achieved by conventional AIEgens and aggregation-caused quenching luminogens with similar structures. TPE-MI outperforms the benchmark luminol-based technique in visualizing latent bloodstains as showcased in two mock crime scenes: spattered blood track and transfer blood fingerprint. This disclosed method is an advancement in forensic science that could inspire future development of technology for bloodstain visualization.


Assuntos
Manchas de Sangue , Ciências Forenses , Albumina Sérica/química , Estilbenos/química , Química Click , Crime , Hemoglobinas/química , Humanos , Luminol/química , Albumina Sérica/isolamento & purificação , Estilbenos/isolamento & purificação
10.
Fitoterapia ; 134: 151-157, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30825571

RESUMO

Bioassay-guided fractionation of the leaves of Macaranga barteri collected from Nigeria led to the isolation of three previously undescribed cytotoxic stilbenes, macabartebenes A-C (1-3), together with six known compounds including prenylated stilbenes: vedelianin (4), schweinfurthin G (5), and mappain (7), prenylated flavonols: 8-prenylkaempferol (6), and broussoflavonol F (8), and the geranylated flavonol, isomacarangin (9). The cytotoxicity of the compounds was evaluated against four human cancer cell lines, with vinblastine as the positive control and DMSO vehicle as the negative control. Vedelianin (IC50 = 0.32-0.54 µM) displayed the greatest antiproliferative activity across the panel of cancer cell lines amongst the compounds, while macabartebene A (IC50 = 0.60-0.79 µM) was the most potent of the previously unreported compounds. The compounds displayed varying selectivity towards the cancer cell lines compared to the normal human prostate cell line. The findings of this study revealed that M. barteri leaves contain several cytotoxic compounds.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Euphorbiaceae/química , Flavonóis/farmacologia , Estilbenos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Bioensaio , Linhagem Celular Tumoral , Fracionamento Químico , Ensaios de Seleção de Medicamentos Antitumorais , Flavonóis/isolamento & purificação , Humanos , Estrutura Molecular , Nigéria , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Folhas de Planta/química , Estilbenos/isolamento & purificação
11.
Fitoterapia ; 134: 264-269, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30825577

RESUMO

Five new compounds including two stilbenes, designated thujasutchins A (1) and B (2), two phenolic compounds namely thujasutchins C (3) and D (4), as well as one sesquiterpene thujasutchin E (5), were isolated from the 95% ethanolic extract from the trunks and roots of Thuja sutchuenensis. Their structures were determined by means of extensively spectroscopic analysis including UV, IR, HRESIMS, 1H and 13C NMR (COSY, HSQC, HMBC). Moreover, compounds 1, 3-5 were evaluated for in vitro cytotoxic activities against SF-268, MCF-7, HepG-2, and A549 tumor cell lines.


Assuntos
Sesquiterpenos/química , Estilbenos/química , Thuja/química , Linhagem Celular Tumoral , China , Humanos , Estrutura Molecular , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Raízes de Plantas/química , Sesquiterpenos/isolamento & purificação , Estilbenos/isolamento & purificação
12.
Anal Chim Acta ; 1054: 59-73, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30712594

RESUMO

A new, relatively simple sample processing and detection workflow has been developed for the quantification and confirmation of banned growth-promoting substances in a wide variety of animal-based food products. The method covers all required compounds (belonging to the so-called A1, A3, A4 and B2f groups as termed by the relevant EU legislation) which are currently monitored by the official European community surveillance programs. The sample processing includes a thermal sample denaturation step, intended to prevent undesirable side-reactions during the following enzymatic deconjugation of covalently bound analytes. A pH-adjusted dual liquid/liquid-extraction produces sufficient clean extracts for a wide range of matrices (urine, muscle, liver, serum, full blood). The method has been validated using two hybrid quadrupole high-resolution mass spectrometers (Orbitrap and time-of-flight technology-based instruments). Full-scan data acquisition, interlaced with targeted modes (unit mass isolation of the precursors, followed by collision-induced fragmentation), produces sufficiently sensitive and selective detection of the analytes within all the validated matrices. The proposed method is an alternative to currently used methods that are restricted to a limited set of analytes and matrices.


Assuntos
Análise de Alimentos/métodos , Lactonas/análise , Espectrometria de Massas/métodos , Esteroides/análise , Estilbenos/análise , Métodos Analíticos de Preparação de Amostras , Animais , Concentração de Íons de Hidrogênio , Lactonas/química , Lactonas/isolamento & purificação , Extração Líquido-Líquido , Esteroides/química , Esteroides/isolamento & purificação , Estilbenos/química , Estilbenos/isolamento & purificação
13.
Bioorg Chem ; 85: 498-504, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30802806

RESUMO

A new prenylated flavonostilbene, namely, alopecurone P together with three known compounds sophoraflavanone G, 2-(4-hydroxyphenyl)-2,3-dihydrobenzo[b]furan-3,4,6-triol and alopecurone J were characterized from the roots of Sophora pachycarpa. The absolute configuration of alopecurones J and P were characterized by comparison of experimental electronic circular dichroism (ECD) spectroscopy and simulated data using time-dependent density functional theory (TDDFT) for possible stereoisomers. The cytotoxic properties of isolated compounds have also been evaluated on two breast cancer cell lines (MCF-7 and MDA-MB-231) and normal cell line (NIH/3T3) using AlamarBlue®, flowcytometry and western blot assays. Alopecurone J and P showed cytotoxic effect on MCF-7 cell line through Wnt signaling pathway. It seems that the presence of lavandulyl substitution in C-8 position of flavanone structure increased the cytotoxic effect.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flavonoides/farmacologia , Sophora/química , Via de Sinalização Wnt/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Teoria da Densidade Funcional , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Modelos Químicos , Raízes de Plantas/química , Estilbenos/química , Estilbenos/isolamento & purificação , Estilbenos/farmacologia , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/farmacologia
14.
J Sep Sci ; 42(6): 1202-1209, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30653252

RESUMO

A valid and reliable method was established to separate six compounds from pigeon pea leaves via elution-extrusion counter-current chromatography. A solvent system composed of n-hexane/methanol/formic acid aqueous solution with pH = 3 (10:6:4, v/v) was screened to achieve satisfactory isolation from the ethanol extract of pigeon pea leaves. Four compounds, 9.2 mg of compound 1 (96.8%), 3.2 mg of 2 (88.0%), 6.2 mg of 4 (94.2%) and 25.2 mg of 5 (94.2%), were obtained by conventional elution from 100 mg of the precipitation fraction, respectively. Two compounds, 14.4 mg of 3 (96.3%) and 28.1 mg of 6 (96.6%), with high K values were obtained by the subsequent extrusion procedure. The compounds 1-6 were identified as 3-methoxy-5-(2-phenylethenyl)-phenol, pinostrobin chalcone, pinostrobin, 2-hydroxy-4-methoxy-6-(2-phenylvinyl)-benzoic acid, longistylin C and cajaninstilbene acid by quadrupole time-of-flight mass spectrometry, and 1 H and 13 C NMR spectroscopy. The in vitro antiproliferation activities of compounds 1, 5 and 6 against human hepatoma cell were evaluated and the half-maximum inhibitory concentrations were acquired.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ácido Benzoico/farmacologia , Flavanonas/farmacologia , Ervilhas/química , Fenóis/farmacologia , Salicilatos/farmacologia , Estilbenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Ácido Benzoico/química , Ácido Benzoico/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Distribuição Contracorrente , Ensaios de Seleção de Medicamentos Antitumorais , Flavanonas/química , Flavanonas/isolamento & purificação , Células Hep G2 , Humanos , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Folhas de Planta/química , Salicilatos/química , Salicilatos/isolamento & purificação , Estilbenos/química , Estilbenos/isolamento & purificação
15.
Nat Prod Res ; 33(20): 2958-2963, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30468086

RESUMO

Myristigranol, a new diarylpropane derivative, was isolated from the methanol extract of Myristica fragrans wood along with one diarylpropanoid and three stilbenoids. The isolated constituents were exhaustingly identified using the analyses of 1D and 2D NMR spectroscopic techniques and comparison of the literatures reported as well. The antioxidant activity was also determined.


Assuntos
Myristica/química , Propano/análogos & derivados , Madeira/química , Antioxidantes/farmacologia , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Propano/isolamento & purificação , Propano/farmacologia , Estilbenos/isolamento & purificação
16.
J Asian Nat Prod Res ; 21(2): 117-122, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29063787

RESUMO

Two new stilbenoids, named 2,3 -dimethoxyl-7-hydroxyl-1,4-phenanthrenedione (1) and 2-methoxyl-3-methyl-7-hydroxyl-9,10-dihydro-1,4-phenanthrenedione (2), together with two known stilbenoids including densiflorol B (3) and ephemeranthoquinone (4), were isolated from aerial parts of Flickingeria fimbriata (Bl.) Hawkes. The structures of two new compounds were elucidated by extensive spectroscopic analysis, including HRESIMS, 1H and 13C NMR, DEPT, HMBC, COSY, HMQC, NOESY. All the compounds were obtained from this genus for the first time. In addition, they all exhibited moderate cytotoxic activities against HepG2 cell lines.


Assuntos
Orchidaceae/química , Componentes Aéreos da Planta/química , Sesquiterpenos/isolamento & purificação , Estilbenos/isolamento & purificação , Medicamentos de Ervas Chinesas , Células Hep G2/efeitos dos fármacos , Humanos , Estrutura Molecular , Sesquiterpenos/química , Sesquiterpenos/toxicidade , Estilbenos/química , Estilbenos/toxicidade
17.
Nat Prod Res ; 33(16): 2300-2307, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29468894

RESUMO

Phytochemical investigation of the stems of Vatica mangachapoi (Dipterocarpaceae) led to the isolation and structural elucidation of twenty-seven oligostilbenes (1-27), including a new natural compound 1. The structure of 1 was elucidated on the basis of spectroscopic analyses including NMR, MS and ECD data, and the known compounds were identified by comparisons with those reported in the literature. The absolute configuration of 1 was first time determined by a combination of NOESY spectrum and quantum chemical computation. Among of isolates were tested for their anti-osteoporosis and anti-HIV-1 activities in vitro by the MTT method. Moreover, the chemotaxonomic significance of these compounds was summarised.


Assuntos
Dipterocarpaceae/química , Estilbenos/isolamento & purificação , Fármacos Anti-HIV/farmacologia , Espectroscopia de Ressonância Magnética , Osteoporose/tratamento farmacológico , Caules de Planta/química , Estilbenos/química , Estilbenos/classificação , Estilbenos/farmacologia
18.
Nat Prod Res ; 33(3): 420-426, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29569485

RESUMO

Two new dihydrophenanthrenes, dendroinfundin A (1) and dendroinfundin B (2) were isolated from the whole plant of Dendrobium infundibulum, together with 7 known compounds (3-9). The structures of the new compounds (1 and 2) were established on the basis of their spectroscopic data. All of the isolates were evaluated for their α-glucosidase and pancreatic lipase inhibitory activities. Batatasin III (5) and dendrosinen B (9) showed strong α-glucosidase inhibitory activity. Dendrosinen B (9) also exhibited appreciable pancreatic lipase inhibitory effect.


Assuntos
Dendrobium/química , Fenantrenos/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Lipase/antagonistas & inibidores , Estrutura Molecular , Fenantrenos/química , Estilbenos/isolamento & purificação , Estilbenos/farmacologia , alfa-Glucosidases/efeitos dos fármacos
19.
Am J Chin Med ; 46(8): 1841-1859, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30537866

RESUMO

Cholesterol metabolism becomes imbalanced during the formation of macrophage-derived foam cells. Pre-B-cell colony-enhancing factor (PBEF) has recently been found to affect lipid deposition and inflammation in atherosclerosis. Here, we aimed to study the effects and molecular mechanism of Polydatin on atherosclerosis in ApoE-knockout (ApoE -∕- ) mice. Thirty ApoE -∕- mice were fed a high-fat diet (HFD) for 12 weeks, and then treated with Polydatin for another 12 weeks. Whole aortas and cryosections were stained with oil red O. Blood lipid, PBEF and cytokine levels were measured by ELISA. The mRNAs of cholesterol metabolism-related genes were determined by qRT-PCR and protein levels by Western blotting. Cell cholesterol content and viability were determined in macrophages and RAW 264.7 cells. PBEF siRNA was used to study the effect of Polydatin on cholesterol metabolism in macrophages incubated with ox-LDL. Polydatin lowered blood lipids and decreased atherosclerotic lesions in ApoE -∕- mice. The expression of cytokines and the mRNA of cholesterol metabolism-related genes were markedly regulated by Polydatin. Meanwhile, PBEF mRNA and protein were both greatly down-regulated by Polydatin. In vitro, Polydatin protected RAW 264.7 cells treated by ox-LDL and inhibited cholesterol uptake by macrophages. The PBEF siRNA result indicates that Polydatin can modulate cholesterol metabolism in macrophages, partly through down-regulation of PBEF. In conclusion, Polydatin relieves atherosclerosis injury in ApoE -∕- mice, mainly through down-regulation of PBEF and inhibition of PBEF-inducing cholesterol deposits in macrophages.


Assuntos
Aterosclerose/tratamento farmacológico , Aterosclerose/genética , Colesterol/metabolismo , Citocinas/genética , Citocinas/fisiologia , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Macrófagos/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/fisiologia , Fitoterapia , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Animais , Aterosclerose/metabolismo , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Glucosídeos/isolamento & purificação , Camundongos , Camundongos Knockout , Nicotinamida Fosforribosiltransferase/metabolismo , Células RAW 264.7 , RNA Interferente Pequeno , Estilbenos/isolamento & purificação
20.
Fitoterapia ; 131: 119-126, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30352293

RESUMO

Stilbene derivatives, the principal constituent of Rheum undulatum L., are known to have a wide range of biological activities, such as anti-allergic, anti-diabetic, antioxidant, and anti-inflammatory activities. A phytochemical study on the methanol extract of Korean rhubarb (R. undulatum L.) led to the isolation of nine stilbene derivatives (1-9) and one flavonoid (10). All structures were elucidated based on a comprehensive analysis of spectroscopic data. Compound 1 (5-methoxy-cis-rhapontigenin) was elucidated as a new compound, while compound 2 (5-methoxy-trans-rhapontigenin) was isolated from a natural source for the first time. Among the isolated compounds, stilbene derivatives (7-9) showed a strong inhibitory effect on protein tyrosine phosphatase 1B (PTP1B) with IC50 values ranging from 4.25 to 6.78 µM, which was significantly higher than that of the positive control, ursolic acid (IC50 = 11.34 µM). Furthermore, for the first time, kinetic analysis and molecular docking simulations were performed in order to understand the inhibition type as well as the interaction and binding mode of the active stilbenes (7-9) with PTP1B. Our results showed that the types of PTP1B inhibition were noncompetitive for ɛ-viniferin (8) and mixed for piceatannol (7) and δ-viniferin (9). Docking simulations of these stilbenes demonstrated negative binding energies and close proximity to residues in the binding pocket of PTP1B.


Assuntos
Proteína Tirosina Fosfatase não Receptora Tipo 1/antagonistas & inibidores , Rheum/química , Rizoma/química , Estilbenos/farmacologia , Benzofuranos , Domínio Catalítico , Simulação de Acoplamento Molecular , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , República da Coreia , Resorcinóis , Estilbenos/isolamento & purificação
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