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1.
J Agric Food Chem ; 67(32): 9002-9008, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31322885

RESUMO

The diphenylurea 4,4'-dinitrocarbanilide (DNC) is the residue of concern left in edible tissues of broilers fed diets containing the anticoccidial nicarbazin. When chicken meat is submitted to thermal processing, p-nitroaniline (p-NA) is expected from DNC degradation. This work aimed at evaluating whether thermal processing of DNC-containing chicken meat induces p-NA appearance. First, a hydrolysis assay was performed in aqueous solutions at 100 °C in different pH, confirming that DNC cleavage yields p-NA. Then a novel LC-MS/MS method was used to detect traces of this aromatic amine in DNC-containing chicken breast fillets subjected to cooking methods. Our evidence showed p-NA occurrence in such chicken meat samples, which corroborated results from hydrolysis assay. The p-NA appearance in fillets was rather discrete during boiling treatment, but its concentration became pronounced over time for grilling, frying, and roasting, achieving respectively 326.3, 640.0, and 456.9 µg/kg. As far as we are concerned, no other research identified degradation products from DNC residue in heat-processed chicken fillets. Therefore, this study leads to additional approaches to assess impacts on food safety.


Assuntos
Compostos de Anilina/química , Carbanilidas/química , Coccidiostáticos/química , Resíduos de Drogas/química , Carne/análise , Nicarbazina/química , Compostos de Anilina/metabolismo , Animais , Carbanilidas/metabolismo , Galinhas/metabolismo , Coccidiostáticos/metabolismo , Culinária , Resíduos de Drogas/metabolismo , Temperatura Alta , Nicarbazina/metabolismo , Espectrometria de Massas em Tandem
2.
J Agric Food Chem ; 67(27): 7609-7615, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31257874

RESUMO

Shallow water systems are uniquely susceptible to environmental processes such as photolysis and hydrolysis that can influence the dissipation of pesticides into sediments. The fungicide dicloran has previously been shown to undergo photolysis and is reported to dissipate in soils and sediments. The photodegradation and dissipation of dicloran in freshwater and seawater was monitored in a laboratory-simulated shallow water system. While no difference was observed between freshwater and seawater systems in the presence of simulated sunlight, the dissipation of dicloran in dark trial systems differed between salinities; 30% of the applied mass dissipated into the sediment in freshwater vs 22% in seawater, and the photodegradation rate and half-life were also impacted by the presence of sediment. The potential for dicloran to dissipate and photodegrade affects the overall behavior of dicloran between waters. Differences in chemical behavior with sediment presence and potential for photodegradation have the capacity to impact organisms within the ecosystem and suggest that these factors may need to be implemented into chemical exposure assessments dependent upon location.


Assuntos
Compostos de Anilina/química , Água Doce/química , Sedimentos Geológicos/química , Fotólise , Água do Mar/química , Luz Solar , Ecossistema , Fungicidas Industriais/química , Solo/química , Poluentes Químicos da Água/química
3.
Chem Commun (Camb) ; 55(65): 9697-9700, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31347623

RESUMO

An ultra-high sensitivity sensor with the function of chiral signal amplification has been proposed for the enantiomer discrimination of various amino acid enantiomers based on charge transfer (CT)-induced SERS spectroscopy. The introduced TiO2 in this sensor improves the CT behavior and discrimination efficiency distinctly and enantiomeric discrimination is realized even at low concentration.


Assuntos
Compostos de Anilina/química , Nanopartículas Metálicas/química , Compostos de Sulfidrila/química , Triptofano/análise , beta-Ciclodextrinas/química , Ligações de Hidrogênio , Fenilalanina/análise , Fenilalanina/química , Prata/química , Análise Espectral Raman/métodos , Estereoisomerismo , Titânio/química , Triptofano/química , Tirosina/análise , Tirosina/química
4.
Chem Commun (Camb) ; 55(58): 8494-8497, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31268095

RESUMO

A rational strategy was reported to construct boranil complexes (DPFB derivatives) with unique aggregation-induced emission effects by installing phenyl rings in the anil ligand as the intramolecular rotors. In view of the good biocompatibility and suitable lipophilicity, DPFB derivatives can serve as excellent fluorescent probes for specific imaging of lipid droplets in living cells and yolk lipids in zebrafish.


Assuntos
Compostos de Anilina/química , Compostos de Boro/química , Complexos de Coordenação/química , Corantes Fluorescentes/química , Gotículas Lipídicas/metabolismo , Compostos de Anilina/síntese química , Animais , Compostos de Boro/síntese química , Complexos de Coordenação/síntese química , Fluorescência , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Ligantes , Microscopia Confocal/métodos , Estrutura Molecular , Peixe-Zebra
5.
Carbohydr Polym ; 219: 423-430, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151543

RESUMO

Colloidal polyaniline dispersions stabilized with biocompatible polysaccharides, sodium hyaluronate and chitosan (both with two different molecular weights), were successfully formulated. The colloids were characterized by UV-vis spectra, particle-size distributions and morphology, as well as by their biological properties in terms of cytotoxicity and antibacterial activity. Colloids containing both chitosan and hyaluronate showed only mild cytotoxicities, which were mainly governed by the concentration of conducting polyaniline in the colloid. Antibacterial activity of the samples, however, depended both on the type of polysaccharide and the ratio between the stabilizer and polyaniline mass. The colloid synthetized using 0.2 M aniline hydrochloride, 0.1 M ammonium persulfate, and 1 wt.% sodium hyaluronate of molecular weight of 1.8-2.1 × 106 exhibited the highest antibacterial activity against both gram positive and gram negative bacteria. This formulation, therefore, allowed for the formation of potentially stimuli-responsive antibacterial colloidal particles with low cytotoxicity.


Assuntos
Compostos de Anilina , Antibacterianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Coloides , Ácido Hialurônico/química , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Animais , Coloides/química , Coloides/farmacologia , Escherichia coli/efeitos dos fármacos , Camundongos , Células NIH 3T3 , Nanocompostos/química , Staphylococcus aureus/efeitos dos fármacos
6.
Anal Bioanal Chem ; 411(16): 3631-3640, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31175397

RESUMO

In this research, electrospun polycaprolactam nanofibers were collected on a fine stainless steel mesh sheet without a binder, and a layer of conductive polyaniline was chemically deposited on the nanofibers. The polyaniline immobilized on the polycaprolactam nanofibers provided high electrical conductivity, acceptable mechanical stability, and a large surface area. This assembly was then used as a working electrode in electrochemically controlled solid-phase microextraction (EC-SPME), a fast and environmentally friendly method. The polymer layers were characterized by SEM and FTIR techniques. Significant factors affecting the EC-SPME efficiency were investigated, including the desorption conditions, the sorbent used, the pH of the sample solution, the extraction voltage, the extraction time, and the ionic strength. Under the optimum conditions, the limits of detection and quantification for the target analytes were 0.9-1.8 µg L-1 and 3.0-6.1 µg L-1, respectively. The linear dynamic range was 5-2000 µg L-1, with R2 > 0.993. The method was coupled with HPLC analysis and applied to the determination of angiotensin ΙΙ receptor antagonists (ARA-ΙΙs) in human plasma, and relative recoveries of 91.1-104.3% with RSDs of ≤8.3% were obtained.


Assuntos
Antagonistas de Receptores de Angiotensina/sangue , Compostos de Anilina/química , Caprolactama/química , Cromatografia Líquida de Alta Pressão/métodos , Técnicas Eletroquímicas/métodos , Nanofibras/química , Microextração em Fase Sólida/métodos , Adsorção , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Concentração Osmolar , Reprodutibilidade dos Testes , Solventes/química , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Anal Bioanal Chem ; 411(20): 5175-5186, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31187200

RESUMO

An ultrasensitive electrochemiluminescence (ECL) immunosensor for alpha-fetoprotein (AFP) detection based on a poly(aniline-luminol)/graphene oxide nanocomposite was developed. The nanocomposite, which was prepared using a fast and simple chemical oxidation strategy for the first time, showed excellent ECL performance. This outstanding ECL performance is due to the formation of poly(aniline-luminol) on the graphene oxide (GO) surface and the excellent electron-transfer properties of GO. Moreover, the poly(aniline-luminol)/graphene oxide nanocomposite has abundant amino groups at its surface, making it a good platform for biomacromolecule labeling. Using the nanocomposite, a novel ECL immunosensor for the determination of AFP was successfully developed. Anti-AFP was immobilized on the surface of a poly(aniline-luminol)/graphene oxide nanocomposite-modified electrode using a glutaraldehyde crosslinking method to form the ECL immunosensor. The AFP was then captured at the modified electrode surface through an antigen-antibody immunoreaction. When the AFP was captured by its antibody, the ECL intensity decreased. This ECL immunosensor for the detection of AFP exhibited a linear range of 1.7 × 10-12 to 1.7 × 10-8 mg mL-1 and a detection limit of 5 × 10-13 mg mL-1, indicating high sensitivity and linearity across a wide concentration range. Furthermore, the immunosensor was successfully applied to determine AFP in a real-world human serum sample. Graphical abstract A new poly(aniline-luminol)/graphene oxide nanocomposite was prepared using a fast and simple strategy for the first time, and an ultrasensitive electrochemiluminescence (ECL) immunosensor for alpha-fetoprotein (AFP) detection based on this nanocomposite was developed.


Assuntos
Compostos de Anilina/química , Técnicas Biossensoriais , Técnicas Eletroquímicas/métodos , Grafite/química , Luminescência , Luminol/química , Nanocompostos/química , alfa-Fetoproteínas/análise , Humanos , Limite de Detecção , Microscopia Eletrônica de Transmissão , Reprodutibilidade dos Testes , Soro , Espectrofotometria Ultravioleta , Análise Espectral Raman , alfa-Fetoproteínas/imunologia
8.
Bioelectrochemistry ; 129: 144-153, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31158799

RESUMO

A microbial fuel cell (MFC) is a potential bio-electrochemical technology that utilizes microorganisms to convert chemical energy into electrical energy. The low power output of MFCs remain the bottleneck for their practical applications. In this paper, a novel, biocompatible and bioelectrocatalytic composite chitosan-nitrogen doped carbon nanotubes-polyaniline (CS-NCNT-PANI) was prepared in situ on the 3D porous NCNT/sponge and applied to an MFC anode. The PANI was grafted on the CS-NCNT backbone to synthesize the ternary composite. This bioanode not only increased the active surface area and capacity but also facilitated bacterial adhesion and enrichment of microbes. Compared with the NCNT/sponge electrode, the charge transfer impedance of the ternary composite bioanode decreased from 14.07â€¯Ω to 2.25 Ω, and the maximum power density increased from 1.4 W·m-3 to 4.2 W·m-3; meanwhile, during the chronoamperometric experiment with a charge-discharge time of 60-60 min, the cumulative charge of the composite bioanode was 18,865.8 C·m-2, which is much higher than that of the NCNT/S anode (3625.3 C·m-2). High-throughput sequencing technology revealed that the ternary composite bioanode had good biocompatibility and high diversity. Therefore, this synthesized ternary composite is a promising candidate as a capacitive and biocompatible anode material in MFC.


Assuntos
Compostos de Anilina/química , Fontes de Energia Bioelétrica , Quitosana/química , Nanotubos de Carbono/química , Bactérias/genética , Bactérias/isolamento & purificação , Materiais Biocompatíveis/química , Fontes de Energia Bioelétrica/microbiologia , Biomassa , Eletricidade , Eletrodos/microbiologia , Nanotubos de Carbono/ultraestrutura , Filogenia , Porosidade
9.
Eur J Med Chem ; 178: 214-231, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31185412

RESUMO

Discovery of antimicrobial agents with a novel model of action is in urgent need for the clinical management of multidrug-resistant bacterial infections. Recently, we reported the identification of a first-in-class bacterial ribosomal RNA synthesis inhibitor, which interrupted the interaction between the bacterial transcription factor NusB and NusE. In this study, a series of diaryl derivatives were rationally designed and synthesized based on the previously established pharmacophore model. Inhibitory activity against the NusB-NusE binding, circular dichroism of compound treated NusB, antimicrobial activity, cytotoxicity, hemolytic property and cell permeability using Caco-2 cells were measured. Structure-activity relationship and quantitative structure-activity relationship were also concluded and discussed. Some of the derivatives demonstrated improved antimicrobial activity than the hit compound against a panel of clinically important pathogens, lowering the minimum inhibition concentration to 1-2 µg/mL against Staphylococcus aureus, including clinical strains of methicillin-resistant Staphylococcus aureus at a level comparable to some of the marketed antibiotics. Given the improved antimicrobial activity, specific inhibition of target protein-protein interaction and promising pharmacokinetic properties without significant cytotoxicity, this series of diaryl compounds have high potentials and deserve for further studies towards a new class of antimicrobial agents in the future.


Assuntos
Compostos de Anilina/farmacologia , Antibacterianos/farmacologia , Benzilaminas/farmacologia , Ligação Proteica/efeitos dos fármacos , Bases de Schiff/farmacologia , Compostos de Anilina/síntese química , Compostos de Anilina/química , Compostos de Anilina/toxicidade , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/toxicidade , Proteínas de Bactérias/metabolismo , Benzilaminas/síntese química , Benzilaminas/química , Benzilaminas/toxicidade , Células CACO-2 , Desenho de Drogas , Eritrócitos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Células HeLa , Hemólise/efeitos dos fármacos , Humanos , Queratinócitos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Bases de Schiff/síntese química , Bases de Schiff/química , Bases de Schiff/toxicidade , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
10.
Chem Asian J ; 14(15): 2662-2675, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31149777

RESUMO

Chicken feather-derived high-surface-area porous activated carbon (CFAC) material was prepared using chemical activation. A new composite composed of Ru-Pd nanoparticles supported on CFAC (Ru-Pd@CFAC) has been prepared by microwave-thermal reduction in the presence of the support. Characterization by XRD, Raman, BET, FE-SEM/TEM, FT-IR, TGA, XPS, HAADF-STEM-EDS, H2 -chemisorption, H2 -TPR, and ICP-AES was used to analyze the catalyst. This catalyst is found to be efficient for the reduction of hexavalent chromium (CrVI ), potassium ferricyanide (K3 [Fe(CN)6 ]), 4-nitrophenol (4-NP), and pendimethalin (PDM), at room temperature, and remains stable, even after several repeated runs. Moreover, it showed excellent catalytic activity compared with the monometallic counterparts.


Assuntos
Ligas/química , Carbono/química , Nanopartículas Metálicas/química , Paládio/química , Rutênio/química , Compostos de Anilina/química , Animais , Catálise , Galinhas , Cromo/química , Ferricianetos/química , Nitrofenóis/química , Oxirredução , Porosidade , Reciclagem , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Eliminação de Resíduos Líquidos
11.
Chem Commun (Camb) ; 55(51): 7410-7413, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31180411

RESUMO

A red fluorescent probe (Mito-V) with a long lifetime was designed to monitor viscosity changes with high selectivity and sensitivity. The fluorescence intensity and lifetime of Mito-V displayed a good relationship with the viscosity value, and Mito-V was successfully applied to sensing mitochondrial viscosity changes in living cells under different biological processes.


Assuntos
Compostos de Anilina/química , Benzaldeídos/química , Corantes Fluorescentes/química , Indóis/química , Mitocôndrias/metabolismo , Técnicas Biossensoriais , Células Hep G2 , Humanos , Imagem Óptica , Viscosidade
12.
Chem Commun (Camb) ; 55(44): 6213-6216, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31073582

RESUMO

The first example of room temperature non-noble metal homogeneous system catalyzed selective N-alkylation of anilines with alcohols by a bis-NHC manganese complex is presented. This system was applied to a large range of alcohols and anilines, including biologically relevant motifs and challenging methanol. Experimental and computational studies suggest an outer-sphere mechanism for this NHC-Mn system.


Assuntos
Álcoois/química , Compostos de Anilina/química , Compostos Heterocíclicos/química , Manganês/química , Metano/análogos & derivados , Alquilação , Catálise , Metano/química , Temperatura Ambiente
13.
Chem Pharm Bull (Tokyo) ; 67(5): 445-451, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061369

RESUMO

Electrodeposition is commonly used to deposit ceramic or metal coating on metallic implants. Its utilization in depositing polymer microcapsule coating is currently being explored. However, there is no encapsulation of drug within polymer microcapsules that will enhance its chemical and biological properties. Therefore, in this study, ginseng which is known for its multiple therapeutic effects was encapsulated inside biodegradable poly(lactic-co-glycolic acid) (PLGA) microcapsules to be coated on pre-treated medical grade stainless steel 316L (SS316L) using an electrodeposition technique. Polyaniline (PANI) was incorporated within the microcapsules to drive the formation of microcapsule coating. The electrodeposition was performed at different current densities (1-3 mA) and different deposition times (20-60 s). The chemical composition, morphology and wettability of the microcapsule coatings were characterized through attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM) and contact angle analyses. The changes of electrolyte colors, before and after the electrodeposition were also observed. The addition of PANI has formed low wettability and uniform microcapsule coatings at 2 mA current density and 40 s deposition time. Reduction in the current density or deposition time caused less attachment of microcapsule coatings with high wettability records. While prolonging either one parameter has led to debris formation and melted microcapsules with non-uniform wettability measurements. The color of electrolytes was also changed from milky white to dark yellow when the current density and deposition time increased. The application of tolerable current density and deposition time is crucial to obtain a uniform microcapsule coating, projecting a controlled release of encapsulated drug.


Assuntos
Compostos de Anilina/química , Materiais Revestidos Biocompatíveis/química , Galvanoplastia/métodos , Panax/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Aço Inoxidável/química , Cápsulas , Composição de Medicamentos/instrumentação , Composição de Medicamentos/métodos , Galvanoplastia/instrumentação , Desenho de Equipamento , Próteses e Implantes
14.
J Agric Food Chem ; 67(24): 6892-6901, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31125221

RESUMO

We herein describe a high-throughput 96-well plate micro-solid phase extraction sample preparation technique based on novel sulfonated-polyaniline/polyacrylonitrile nanofiber mats (sulfonated-PANI/PAN NFMs) for multiresidue detection of fluoroquinolones (FQs) in various animal-origin food samples. Through the double-modification of polyaniline and sulfonic acid, the resulting functionalized sulfonated-PANI/PAN NFMs present high extraction efficiency for FQs. Compared with the existing methods, this approach demonstrates its advantages of being suitable for more sample matrices (milk, animal muscle, liver, kidney, and egg), lower sample amount (0.5 g), lower sorbent requirement (5.0 mg), lower volume of organic solvent (0.7 mL), shorter time (0.2 min per sample), and high sensitivity (0.012-0.06 µg·kg-1). In addition, sulfonated-PANI/PAN NFMs possess excellent reusability which could be reused 10 times without an obvious decrease in extraction efficiency. Combined with ultra performance liquid chromatography-tandem mass spectrometry, the novel sample preparation technique can be expected as an efficient method for routine trace FQ residue monitoring in animal-origin food samples.


Assuntos
Anti-Infecciosos/análise , Anti-Infecciosos/isolamento & purificação , Fluoroquinolonas/análise , Fluoroquinolonas/isolamento & purificação , Contaminação de Alimentos/análise , Ensaios de Triagem em Larga Escala/métodos , Microextração em Fase Sólida/métodos , Resinas Acrílicas/química , Compostos de Anilina/química , Animais , Bovinos , Galinhas , Ovos/análise , Ensaios de Triagem em Larga Escala/instrumentação , Rim/química , Limite de Detecção , Fígado/química , Carne/análise , Leite/química , Nanofibras/química , Microextração em Fase Sólida/instrumentação , Suínos
15.
Carbohydr Polym ; 216: 360-368, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047078

RESUMO

Nanocellulose has functionalities suitable for efficient sensor transducer surface design including crystallinity, biocompatible and high specific surface area. Here we explore two forms of nanocellulose as transducer surfaces to enable colorimetric detection of human neutrophil elastase (HNE), and a wide range of inflammatory diseases. A deep eutectic solvent (DES) was utilized to mediate formation of cotton cellulose nanocrystals (DCNCs) employed to prepare a peptide-cellulose conjugate as a protease sensor of HNE. The tetrapeptide-cellulose analog on DCNC is contrasted with an analogous derivative of TEMPO-oxidized wood cellulose nanofibrils (WCNFs). DCNCs showed greater degree of substitution of HNE tetrapeptide and sensitivity to the elastase than WCNFs, despite the smaller surface area and pore sizes. XRD models revealed the higher crystallinity and larger crystallite sizes of DCNCs, indicating the well-arranged cellulose chains for immobilization of the tetrapeptide on (110) lattice reflections of cellulose crystals. The sensitivity of DCNCs-based colorimetric sensor was less than 0.005 U/mL, which would provide a convenient, sensitive sensor applicable for improved colorimetric point of care protease biomarker detection.


Assuntos
Celulose/química , Elastase de Leucócito/análise , Nanopartículas/química , Compostos de Anilina/química , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Gossypium/química , Humanos , Proteínas Imobilizadas/química , Indicadores e Reagentes/química , Modelos Moleculares , Oligopeptídeos/química , Porosidade , Proteólise , Propriedades de Superfície
16.
Carbohydr Polym ; 216: 54-62, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047082

RESUMO

Biodegradable, antimicrobial, and semiconducting cellulosic composite was synthesized by in-situ polymerization of polyaniline in the presence of cellulose. The cobalt ferrite nanoparticles (CFO-NPs) were added during the polymerization process to acquire this composite magnetic property. The CFO-NPs were prepared by sol-gel method with average particles size less than 50 nm. The nanocomposites were characterized by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). In addition, their magnetic, dielectric constant, dielectric loss, and conductivity behaviors were studied. The magnetization (Ms) and conductivity increased up to 3.7 emu/g and 3.5 × 10-3 S/cm, respectively, with increasing CFO-NPs content. The prepared electromagnetic nanocomposite exhibits highly efficient biodegradability and antimicrobial activity against Escherichia coli, Bacillus subtilis, and Candida albicans. The antimicrobial activity increased with increasing CFO-NPs while the biodegradability decreased.


Assuntos
Compostos de Anilina/farmacologia , Celulose/farmacologia , Cobalto/farmacologia , Compostos Férricos/farmacologia , Nanocompostos/química , Nanopartículas/química , Compostos de Anilina/síntese química , Compostos de Anilina/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/farmacologia , Candida albicans/efeitos dos fármacos , Celulose/análogos & derivados , Celulose/síntese química , Cobalto/química , Condutividade Elétrica , Escherichia coli/efeitos dos fármacos , Compostos Férricos/síntese química , Compostos Férricos/química , Fenômenos Magnéticos , Tamanho da Partícula
17.
Carbohydr Polym ; 217: 135-143, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079669

RESUMO

The parameters to extract polysaccharide-enriched fractions (PEF) from mushrooms using MAE (microwave-assisted extraction) were adjusted following a full factorial 32 experimental design. The highest yield and total carbohydrate values, using Lentinula edodes as model mushroom, were obtained at 180 °C and 30 min. Several mushroom species were submitted to MAE and their PEF yields ranged between 12.1-44.2%. (1→3)-ß-Glucans determination using a conventional fluorimetric method changed depending on the standard utilized. NMR analyses of PEF indicated that the presence of other polysaccharides in the extracts or their specific folding, might impair the proper determination of (1→3) linkages by the fluorophore. Mushrooms from Cantharellales order contained (1→3)-ß-glucans but they were not detected with the fluorimetric method. Therefore, although the method (after adjustments) was sensitive enough to detect their presence in many mushroom extracts, it cannot be used for all species and it is also not recommended for quantitative determinations.


Assuntos
Agaricales/química , Compostos de Anilina/química , Corantes Fluorescentes/química , Extração em Fase Sólida/métodos , beta-Glucanas/isolamento & purificação , Benzenossulfonatos/química , Fluorometria/métodos , Carpóforos/química , Micro-Ondas , beta-Glucanas/química
18.
Molecules ; 24(9)2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31083287

RESUMO

The role of glycerol as a green bio-based solvent, reactant, and/or a catalyst in the synthesis of novel heterocycles, under pressure, is studied. Synthesis of novel quinolines in good yields using a new modified Skraup synthesis, utilizing glycerol and pressure Q-tubes, is demonstrated. Novel aniline trimers are prepared using glycerol, and substituted anilines under pressure, in acidic medium and water. Glycerol was employed as a catalyst and a green solvent in the synthesis of novel pyridazines 13a-c. The mechanisms of the reactions and the catalytic effect of glycerol in protic and aprotic media are fully discussed. The structures of the synthesized compounds were determined via X-ray crystallography and spectroscopic methods.


Assuntos
Compostos de Anilina/química , Glicerol/química , Catálise , Química Verde/métodos , Estrutura Molecular , Quinolinas/química
19.
Analyst ; 144(12): 3773-3781, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31089613

RESUMO

MDM2 is a well-known oncoprotein overexpressed in a variety of cancers, and the identification of inhibitors that disrupt the MDM2/p53 interaction is of great interest in anticancer drug development. Here we designed a platform for the facile and visualizable identification of inhibitors of MDM2 using co-expressed protein complexes of MDM2/p53. A hexahistidine-tag on MDM2 allows the binding of the protein complex to the Ni-NTA affinity resin, while the fluorescent protein fused to p53 enables the direct visualization of the interaction of p53 with MDM2. Hence, the inhibition of the MDM2/p53 interaction can be observed with the naked eye. The assay can be set up by directly loading cell lysate to the Ni-NTA affinity resin, and no chemical modification of proteins is needed. In addition to the qualitative analyses, the binding affinity of inhibitors to the MDM2 protein can be quantified by fluorescence titration. The applications of this system have been verified using small molecules and peptide inhibitors. As a proof of concept, we screened a small library using this platform. Interestingly, two types of novel inhibitors of MDM2, including cyclohexyl-triphenylamine derivatives and platinum complexes, were identified and their binding affinities were obtained. Quantitative measurements show that these new types of inhibitors demonstrate a high binding affinity (up to Kd = 51.9 nM) to MDM2.


Assuntos
Bioensaio/métodos , Proteínas Luminescentes/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Sequência de Aminoácidos , Compostos de Anilina/química , Cromatografia de Afinidade/métodos , Complexos de Coordenação/química , Escherichia coli/genética , Histidina/genética , Histidina/metabolismo , Humanos , Medições Luminescentes/métodos , Proteínas Luminescentes/genética , Simulação de Acoplamento Molecular , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Peptídeos/química , Platina/química , Estudo de Prova de Conceito , Proteínas Proto-Oncogênicas c-mdm2/química , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética
20.
Chem Commun (Camb) ; 55(38): 5515-5518, 2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31020283

RESUMO

A highly sensitive fluorescent probe CBH based on solvatochromism and molecular rotation was designed and developed for imaging of hERG channels by employing a novel targeting group 4-benzylaniline. More importantly, CBH has the potential for the quantitative analysis of the hERG channels expressed in tumor cells.


Assuntos
Compostos de Anilina/química , Canais de Potássio Éter-A-Go-Go/metabolismo , Solventes/química , Animais , Western Blotting , Células CHO , Cricetulus , Canais de Potássio Éter-A-Go-Go/química , Corantes Fluorescentes , Células HeLa , Humanos , Microscopia Confocal
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