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1.
Phys Chem Chem Phys ; 21(44): 24572-24583, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31663551

RESUMO

In this work, poly(N,N'-dimethylaminoethylmethacrylate-co-N-isopropylacrylamide) copolymer films were polymerized on the surface of Au electrodes with a facile one-step method, and Au nanoclusters (AuNCs) and tetraphenylethene (TPE) were synchronously embedded in the films, designated as P(DMA-co-NIPA)/AuNCs/TPE. Ferrocene dicarboxylic acid (FDA), an electroactive probe in solution displayed inverse pH- and SO42--sensitive on-off cyclic voltammetric (CV) behaviors at the film electrodes. The electrocatalytic oxidation of nicotinamide adenine dinucleotide (NADH) mediated by FDA in solution could substantially amplify the CV response difference between the on and off states. Moreover, the two fluorescence emission (FL) signals from the TPE constituent at 450 nm and AuNCs component at 660 nm in the films also demonstrated SO42-- and pH-sensitive behaviors. Based on the aforementioned results, a 4-input/9-output biomolecular logic circuit was constructed with pH, Na2SO4, FDA and NADH as the inputs, and the CV signals and the FL responses at 450 and 660 nm at different levels as the outputs. Additionally, some functional non-Boolean devices were elaborately designed on an identical platform, including a 1-to-2 decoder, a 2-to-1 encoder, a 1-to-2 demultiplexer and different types of keypad locks. This work combines copolymer films, bioelectrocatalysis, and fluorescence together so that more complicated biocomputing systems could be established. This work may pave a new way to develop advanced and sophisticated biocomputing logic circuits and functional devices in the future.


Assuntos
Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , NAD/química , Polímeros/química , Estilbenos/química , Benzoatos/química , Eletrodos , Compostos Ferrosos/química , Ouro/química , Concentração de Íons de Hidrogênio , Oxirredução , Espectrometria de Fluorescência , Sulfatos/química
2.
Inorg Chem ; 58(19): 12700-12706, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31556291

RESUMO

The highly porous luminescent metal-organic frameworks (MOFs) can act as fluorescent probes for the detection of nitro compounds and can also serve as containers and energy transfer platforms to construct the host-guest systems. Herein, two new three-dimensional MOFs with high porosity were prepared successfully by the electron-rich tetrakis(4-pyridylphenyl)ethylene (tppe) as ligands. Compound 1 shows the high sensitivity and selectivity toward nitro-antibiotics in an aqueous media, particularly showing the best detection efficiency for furazolidone (FZD) among the reported luminescent sensors. The highly efficient fluorescence quenching toward FZD may be attributed to the electron and energy transfer. Compound 2 has naphthalene-2,7-dicarboxylic acid (2,7-npd) and tppe as dual linkers, and the energy transfer between 2,7-npd and tppe leads to the emission band in a large scale. It is worth noting that the single-phased white-light materials can be obtained by the in situ encapsulation of different concentration of sulforhodamine 101 (SR101) into compound 2 matrix.


Assuntos
Antibacterianos/análise , Substâncias Luminescentes/química , Estruturas Metalorgânicas/química , Nitrocompostos/análise , Estilbenos/química , Cristalografia por Raios X , Luminescência , Medições Luminescentes , Modelos Moleculares , Rodaminas/química
3.
Eur J Med Chem ; 182: 111597, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31422225

RESUMO

Fatty acid synthase (FASN) is a lipogenic enzyme that is selectively upregulated in malignant cells. There is growing consensus on the oncogenicity of FASN-driven lipogenesis and the potential of FASN as a druggable target in cancer. Here, we report the synthesis and FASN inhibitory activities of two novel galloyl esters of trans-stilbene EC1 and EC5. Inhibition of FASN was accompanied by a loss in AKT activation and profound apoptosis in several non-small cell lung cancer (NSCLC) cells at the growth inhibitory concentrations of EC1 and EC5. Both FASN and phospho-AKT levels were concurrently downregulated. However, addition of a lipid concentrate to the treated cells reinstated cell viability and reversed the loss of FASN and AKT protein levels, thus recapitulating the causal relationship between FASN inhibition and the loss in cell viability.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ésteres/farmacologia , Ácido Graxo Sintase Tipo I/antagonistas & inibidores , Ácido Gálico/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Estilbenos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Ésteres/síntese química , Ésteres/química , Ácido Graxo Sintase Tipo I/metabolismo , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Estrutura Molecular , Estilbenos/síntese química , Estilbenos/química , Relação Estrutura-Atividade
4.
Chem Commun (Camb) ; 55(67): 9959-9962, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31364996

RESUMO

On the basis of BSA stabilized tetraphenylethylene nanocrystals (BSA-TPE NCs) as aggregation-induced enhanced electrochemiluminescence (ECL) emitters with high ECL efficiency and good biocompatibility, as well as molecular recognition between ß-CD and ferrocene, an ultrasensitive and versatile ECL biosensing platform was constructed to achieve microRNA detection in cancer cells.


Assuntos
Materiais Biocompatíveis/química , Corantes Fluorescentes/química , MicroRNAs/análise , Nanopartículas/química , Soroalbumina Bovina/química , Estilbenos/química , Animais , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Bovinos , Linhagem Celular Tumoral , Técnicas Eletroquímicas , Compostos Ferrosos/química , Humanos , Limite de Detecção , Medições Luminescentes , Metalocenos/química , Sensibilidade e Especificidade , beta-Ciclodextrinas/química
5.
Food Chem ; 301: 125297, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394336

RESUMO

Candida antarctica lipase B-catalysed synthesis of lipophilic esters of polydatin was investigated along with their antioxidant activities. The effects of synthesis parameters such as solvent, substrate molar ratio, enzyme concentration, addition of molecular sieves, reaction temperature and time on the production of ester were studied and optimised. The highest production of esters was obtained with acetone as the reaction solvent. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol. All polydatin esters inhibited the oxidative destruction of ß-carotene more effectively than did BHT and α-tocopherol. Results of thiobarbituric acid tests showed that in bulk fish oil, all esters were more effective than α-tocopherol at 2 mmol/kg concentration but were not as effective as BHT. In fish oil-emulsions, all esters were more effective than both BHT and α-tocopherol at 2 mmol/kg concentration. The synthesized polydatin esters are promising antioxidants for oil/fat-based foods.


Assuntos
Antioxidantes/química , Emulsões/química , Óleos de Peixe/química , Glucosídeos/química , Estilbenos/química , Antioxidantes/farmacologia , Hidroxitolueno Butilado/farmacologia , Esterificação , Ésteres/química , Ácidos Graxos/química , Ácidos Graxos Ômega-3/química , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Lipase/química , Lipase/metabolismo , Oxirredução , Solventes/química , Temperatura Ambiente , alfa-Tocoferol/farmacologia
6.
Chem Pharm Bull (Tokyo) ; 67(7): 640-647, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257319

RESUMO

Neuroinflammation manifested by over-activation of microglial cells plays an essential role in neurodegenerative diseases. Short-term activation of microglia can be beneficial, but chronically activated microglia can aggravate neuronal dysfunction possibly by secreting potentially cytotoxic substances such as tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO), which can result in dysfunction and death of neurons. Therefore inhibiting over-activation of microglia and the production of cytotoxic intermediates may become an effective therapeutic approach for neuroinflammation. In this paper, we review our continuous research on natural inhibitors of over-activated microglia from traditional herbals, including flavonoids, lignans, sesquiterpene coumarins, and stilbenes.


Assuntos
Produtos Biológicos/química , Microglia/metabolismo , Animais , Produtos Biológicos/farmacologia , Cumarínicos/química , Cumarínicos/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Lignanas/química , Lignanas/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Óxido Nítrico/biossíntese , Estilbenos/química , Estilbenos/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo
7.
Chem Pharm Bull (Tokyo) ; 67(7): 648-653, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257320

RESUMO

Diabetic embryopathy is a diabetic complication, in which maternal hyperglycemia in early pregnancy causes birth defects in newborn infants. Under maternal diabetic conditions, hyperglycemia disturbs intracellular molecular activities and organelles functions. These include protein misfolding in the endoplasmic reticulum (ER), overproduction of reactive oxygen species (ROS) in mitochondria, and high levels of nitric oxide (NO). The resultant ER, oxidative, and nitrosative stresses activate apoptotic machinery to cause cell death in the embryo, ultimately resulting in developmental malformations. Based on the basic research data, efforts have been made to develop interventional strategies to alleviate the stress conditions and to reduce embryonic malformations. One of the challenges in birth defect prevention is to identify effective and safe agents to be used in pregnancy. One approach is to search and characterize naturally occurring phytochemicals, including flavonoids, curcuminoids and stilbenoids, for use in prevention of diabetic embryopathy.


Assuntos
Anormalidades Congênitas/prevenção & controle , Compostos Fitoquímicos/uso terapêutico , Gravidez em Diabéticas/prevenção & controle , Curcumina/química , Curcumina/farmacologia , Curcumina/uso terapêutico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Gravidez , Estilbenos/química , Estilbenos/farmacologia , Estilbenos/uso terapêutico
8.
Biomater Sci ; 7(9): 3855-3865, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31305807

RESUMO

Fluorogens with aggregation-induced emission (AIE) characteristics (AIEgens) possess unique optical properties, design flexibility, and multi-functional capabilities and have established their niche as smart materials since their discovery in 2001. In recent years, AIEgens have found varied applications in sensing, imaging, and therapy in biomedical research. In this work, we systematically and comprehensively investigate the in vitro anticancer activity of AIEgens. We report the high cytotoxicity of AIEgens against cancer cells, especially against cancer stem cells (CSCs) which show high resistance to existing therapeutic drug regimens. Furthermore, we explore the role of AIEgens as novel image-guided chemotherapy agents that offer a new avenue for efficient cancer treatment.


Assuntos
Antineoplásicos/química , Corantes Fluorescentes/química , Fármacos Fotossensibilizantes/química , Estilbenos/química , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/farmacologia , Hemólise , Humanos , Invasividade Neoplásica , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Imagem Óptica/métodos , Fotoquimioterapia , Estilbenos/farmacologia , Nanomedicina Teranóstica
9.
Molecules ; 24(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167390

RESUMO

The production of secondary metabolites in tissue culture has been considered as an alternative to the cultivation and harvesting of crops intended for this purpose. The present study was aimed at the growth of callus and production of polyphenolic compound of callus derived from a Maltese indigenous grapevine variety, Gellewza. Callus was inoculated onto plant growth regulators-enriched Murashige Skoog media (MSm) to determine whether polyphenols are produced in vitro as well as to determine the best combination of plant growth regulators needed for the production of these metabolites. From results obtained, it was observed that the best callus production was obtained by auxin-enriched MSm. In fact, indole acetic acid and indole acetic acid /6-benzyl aminopurine enhanced biomass accumulation (3.04 g and 3.39 g) as opposed to the others (<1.97 g). On the other hand, parameters showing the presence of flavonoids (tonality, 3.80), particularly anthocyanins (24.09 mg/kg) and total polyphenols (1.42 mg/g), were optimum in the presence of cytokinins, particularly 6-benzyl aminopurine. Analysis for single polyphenols revealed a high amount a particular stilbene: polydatin (glucoside of resveratrol). Resveratrol and other typical polyphenols, found in mature berries, were also found in significant quantities, while the other polyphenolic compounds were found in minimal quantities. This is the first study to describe the production and composition of polyphenols in Gellewza callus cultures. From the results obtained, it can be seen that this grape tissue is an excellent alternative for the production of polyphenols from the stilbene group, which can be upscaled and exploited commercially.


Assuntos
Estilbenos/metabolismo , Vitis/metabolismo , Biomassa , Fenômenos Químicos , Cromatografia Líquida , Espectrometria de Massas , Estrutura Molecular , Reguladores de Crescimento de Planta/metabolismo , Polifenóis/química , Polifenóis/metabolismo , Estilbenos/química , Vitis/química , Vitis/crescimento & desenvolvimento
10.
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
11.
Food Chem ; 295: 10-15, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31174737

RESUMO

The objective of this work is to investigate the inhibition effects on AGEs formation and the ability of scavenging toxic carbonyls of three stilbenes, resveratrol, oxyresveratrol, and piceatannol. The results showed that the three stilbenes had the activity to inhibit the AGEs formation in BSA-acrolein and BSA-methylglyoxal models, especially piceatannol which showed the strongest inhibition effects on the formation of AGEs with the half maximal inhibitory concentrations (IC50) value of 2.44 mM and 0.19 mM in the BSA-acrolein and BSA-methylglyoxal model, respectively. In addition, the three stilbenes showed the ability to scavenge acrolein and methylglyoxal in pH 7.4 at 37 °C. Eight isolated adducts between three stilbenes and toxic carbonyls further confirmed that these three stilbenes could scavenge acrolein and methylglyoxal by forming adducts successfully. Thus, the present study suggested that the consumption of foods containing stilbenes was beneficial for controlling the amount of reactive carbonyl species and the AGEs formation.


Assuntos
Produtos Finais de Glicação Avançada/química , Extratos Vegetais/química , Resveratrol/química , Estilbenos/química , Acroleína/química , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Concentração de Íons de Hidrogênio , Extratos Vegetais/farmacologia , Aldeído Pirúvico/química , Resveratrol/farmacologia , Soroalbumina Bovina/química , Estilbenos/farmacologia , Temperatura Ambiente
12.
Molecules ; 24(11)2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31151290

RESUMO

Polymeric nanoparticle-based carriers are promising agents to deliver drugs to cells. Vitis vinifera phenolic compounds are known for their antifungal activity against Candida albicans. The aim of the present study was to investigate the antifungal activity of pterostilbene or crude extracts from non-fermented grape pomace, entrapped in poly(lactic-co-glycolic) acid nanoparticles (NPs), with diameters of 50 and 150 nm, on Candida biofilm. The fluorescent probe coumarin 6 was used to study the uptake of poly(lactic-co-glycolic)acid (PLGA) NPs in planktonic cells and biofilm. The green fluorescent signal of coumarin 6 was observed in Candida biofilm after 24 and 48 hours. Both pterostilbene and crude pomace extract entrapped in NPs exerted a significantly higher anti-biofilm activity compared to their free forms. The entrapment efficiency of both pterostilbene and crude pomace extract in PLGA NPs was ~90%. At 16 µg/mL, pterostilbene loaded in PLGA NPs reduced biofilm formation of 63% and reduced mature biofilm of 50%. Moreover, at 50 µg/mL, the pomace extract loaded in NPs reduced mature biofilm of 37%. These results strongly suggest that PLGA NPs are promising nanodevices for the delivery of antifungal drugs as the crude grape pomace extract, a by-product of white wine making.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Nanopartículas , Extratos Vegetais/farmacologia , Estilbenos/farmacologia , Antifúngicos/química , Biopolímeros/química , Fenômenos Químicos , Nanopartículas/química , Extratos Vegetais/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Estilbenos/química , Vitis/química
13.
Biol Pharm Bull ; 42(6): 1004-1012, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31155574

RESUMO

Oxyresveratrol (ORV) is a naturally extracted compound with many pharmacological activities. However, information about the crystalline form is not known when considering the development of a form for oral dosage. Cocrystal engineering offers drug molecular understanding and drug solubility improvements. Thus, we attempted cocrystallization of ORV using 10 carboxylic acids as a coformer at a 1:1 M ratio. Each combination was processed with liquid-assisted grinding, solvent evaporation and a slurry method, then characterized by powder X-ray powder diffraction (PXRD), conventional and low-frequency Raman spectroscopy and thermal analysis. The solubility, dissolution and permeation studies across Caco-2 cell monolayers were conducted to evaluate the ORV samples. A screening study revealed that an ORV and citric acid (CTA) cocrystal formed by ethyl acetate-assisted grinding had characteristic PXRD peaks (14.0 and 16.5°) compared to those of ORV dihydrate used as a starting material. Low-frequency Raman measurements, with peaks at 100 cm-1, distinguished potential cocrystals among three processing methods while conventional Raman could not. An endothermic melt (142.2°C) confirmed the formation of the novel crystalline complex. The solubility of the cocrystal in the dissolution media of pH 1.2 and 6.8 was approximately 1000 µg/mL, a 1.3-fold increase compared to ORV alone. In vitro cytotoxicity studies showed that the cocrystal and physical blend were not toxic at concentrations of 25 and 12.5 µM ORV, respectively. The ORV-CTA cocrystal enhanced the cellular transport of ORV across Caco-2 monolayers. Therefore, cocrystallization could be used to improve aqueous solubility and permeability, leading to better oral bioavailability of ORV.


Assuntos
Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estilbenos/química , Estilbenos/farmacologia , Transporte Biológico , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Cristalização , Humanos , Permeabilidade , Solubilidade
14.
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
16.
Chem Biodivers ; 16(6): e1900192, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31107589

RESUMO

Five new trans-2,3,5,4'-tetrahydroxystilbene 2-O-ß-d-glucopyranoside (TSG)-based stilbene glycoside oligomers (1-5) were isolated from the roots of Polygonum multiflorum. Their structures were elucidated by comprehensive spectroscopic analyses and chemical evidences. The absolute configurations of 1, 2, 4, and 5 were established by quantum-chemical electronic circular dichroism (ECD) calculations. Putative biosynthetic pathways of 1-5 were proposed using TSG as the key precursor. In addition, compounds 1 (multiflorumiside H) and 3 (multiflorumiside J) exhibited moderate inhibitory activities against NO production in LPS-stimulated RAW264.7 cells.


Assuntos
Fallopia multiflora/química , Glicosídeos/química , Oligossacarídeos/química , Raízes de Plantas/química , Estilbenos/química , Animais , Dicroísmo Circular , Fallopia multiflora/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Óxido Nítrico/metabolismo , Oligossacarídeos/isolamento & purificação , Oligossacarídeos/farmacologia , Raízes de Plantas/metabolismo , Células RAW 264.7
17.
Phytochemistry ; 164: 12-23, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31060026

RESUMO

Recent experimental work has revealed that the hydroxystilbene piceatannol can function as a monomeric unit in the lignification of palm fruit endocarp tissues. Results indicated that piceatannol homo-couples and cross-couples with monolignols through radical reactions and is integrally incorporated into the lignin polymer. The current work reports on the thermodynamics of the proposed reactions using density functional theory calculations. The results indicated that, in general, the energetics of both homo-coupling and cross-coupling are not dissimilar from those of the monolignol coupling, demonstrating the compatibility of piceatannol with the lignification process. Moreover, the DFT methods appear to predict the correct courses of post-coupling rearomatization reactions.


Assuntos
Teoria da Densidade Funcional , Lignina/química , Estilbenos/química , Radicais Livres/química , Estrutura Molecular , Termodinâmica
18.
Chem Asian J ; 14(13): 2220-2224, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31081238

RESUMO

Water-soluble ratiometric AIE-active fluorescent organic nanoparticles 2OA-FON for the specific sensing of cysteine over other biothiols are reported. The obtained amphiphilic probe included olefin aldehyde as recognizing unit, tetraphenylethylene as fluorescence reporter and lactose moiety as a hydrophilic group. This work provides a general design strategy based on the introduction of a sugar moiety into a hydrophobic AIEgen to develop ratiometric water-soluble fluorescent organic nanoparticles.


Assuntos
Cisteína/análise , Corantes Fluorescentes/química , Glutationa/análise , Homocisteína/análise , Nanopartículas/química , Estilbenos/química , Dimerização , Células Hep G2 , Humanos , Microscopia Confocal , Nanopartículas/ultraestrutura , Imagem Óptica , Solubilidade , Espectrometria de Fluorescência , Água/química
19.
J Environ Radioact ; 204: 117-124, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029985

RESUMO

Atmospheric monitoring of radioxenon is one of the most widely used methods by the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) to detect elevated levels of 131mXe, 133/133mXe, and 135Xe. The ratios of these radionuclides help discriminate between peaceful use of nuclear technology and nuclear weapon explosions. Radioxenon detection systems often use plastic scintillators in the capacity of an electron detector and a gas cell, plastic gas cells are responsible for introducing high memory effect in these systems. This work presents the design of a new detection system for radioxenon monitoring that utilizes silicon photomultipliers, a stilbene gas cell, and a CdZnTe detector. This detector was evaluated using xenon radioisotope samples produced in the TRIGA reactor at Oregon State University. A 48-h background was collected and calculations of the Minimum Detectable Concentration (MDC) were carried out using the Region of Interest (ROI) approach. An MDC of less than 1 mBq/m3 was obtained for 131mXe, 133Xe, and 133mXe in accordance with the sensitivity limits set by the CTBTO and performs respectably when compared to state-of-the-art radioxenon detection systems. Using 131mXe, this study indicates that the stilbene gas cell exhibits a memory effect of 0.045 ±â€¯0.017%, this is almost a two-order magnitude improvement compared to plastic scintillators. The primary purpose of this work is to explore the use of new stilbene detection media for radioxenon application and addressing the problem of memory effect.


Assuntos
Poluentes Radioativos do Ar/análise , Cádmio/química , Monitoramento de Radiação/métodos , Estilbenos/química , Telúrio/química , Radioisótopos de Xenônio/análise , Zinco/química , Explosões , Cooperação Internacional , Armas Nucleares , Monitoramento de Radiação/instrumentação
20.
J Food Sci ; 84(5): 1224-1230, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30990886

RESUMO

Glycyrrhiza uralensis is the major plant source of licorice. This study was to identify bioactive compounds from the plant's leaves in order to make better use of its aerial part. An ethanol extract of the leaves was subjected to repeated chromatography to yield 15 compounds. The structures were determined to be three novel dihydrostilbenes, based on their various spectroscopic data-glycypytilbene A (1), glycydipytilbene (2), and glycypytilbene B (3)-and 12 known compounds, α,α'-dihydro-3,5,4'-trihydroxy-4,3'-diisopentenylstilbene (4), α,α'-dihydro-3,5,3',4'-tetrahydroxy-2,5'-diisopentenylstilbene (5), 6-prenyleriodictyol (6), 5'-prenyleriodictyol (7), 6-prenylquercetin-3-Me ether (8), 5'-prenylquercetin (9), 6-prenylquercetin (10), 6-prenylnaringenin (11), 3'-prenylnaringenin (12), sigmoidin C (13), 8-[(E)-3-hydroxymethyl-2- butenyl]-eriodictyol (14), and quercetin-3-Me ether (15). Most of these chemical constituents inhibited α-glucosidase activity, with the two prenylated quercetin derivatives (9 to 10) being the greatest active (IC50 < 4.0 µg/mL). Compounds 1, 3 to 4, 6 to 7, 9 to 12 impeded the growth of human hepatic stellate cells, with the prenylated flavonoids (6 to 7, 9 to 12) being more robust than their unprenylated counterparts. PRACTICAL APPLICATIONS: This study found that Glycyrrhiza uralensis leaves contain prenylated dihydrostilbenes and flavonoids with inhibiting effects on α-glucosidase and on the proliferation of human hepatic stellate cells, which should prompt the development of G. uralensis leaves for healthy products with anti-diabetic or liver fibrosis-preventing effects.


Assuntos
Proliferação de Células/efeitos dos fármacos , Flavonoides , Glycyrrhiza uralensis/química , Estilbenos , Células Cultivadas , Flavonoides/química , Flavonoides/farmacologia , Hepatócitos/efeitos dos fármacos , Humanos , Estilbenos/química , Estilbenos/farmacologia
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