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1.
Redox Biol ; 71: 103068, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38377790

RESUMO

Following ingestion of fruits, vegetables and derived products, (poly)phenols that are not absorbed in the upper gastrointestinal tract pass to the colon, where they undergo microbiota-mediated ring fission resulting in the production of a diversity of low molecular weight phenolic catabolites, which appear in the circulatory system and are excreted in urine along with their phase II metabolites. There is increasing interest in these catabolites because of their potential bioactivity and their use as biomarkers of (poly)phenol intake. Investigating the fate of dietary (poly)phenolics in the colon has become confounded as a result of the recent realisation that many of the phenolics appearing in biofluids can also be derived from the aromatic amino acids, l-phenylalanine and l-tyrosine, and to a lesser extent catecholamines, in reactions that can be catalysed by both colonic microbiota and endogenous mammalian enzymes. The available evidence, albeit currently rather limited, indicates that substantial amounts of phenolic catabolites originate from phenylalanine and tyrosine, while somewhat smaller quantities are produced from dietary (poly)phenols. This review outlines information on this topic and assesses procedures that can be used to help distinguish between phenolics originating from dietary (poly)phenols, the two aromatic amino acids and catecholamines.


Assuntos
Fenóis , Tirosina , Animais , Fenilalanina , Dieta , Aminoácidos Aromáticos , Polifenóis , Mamíferos/metabolismo
2.
ACS Omega ; 8(35): 32067-32077, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37692231

RESUMO

Iron oxide nanoparticles (Fe3O4NPs) are a fascinating field of study due to their wide range of practical applications in environmental and medical contexts. This study presents a straightforward, environmentally friendly method for producing Fe3O4NPs utilizing ß-cyclodextrin (ß-CD) as a reducing and capping agent. This approach results in the rapid and effective eco-friendly synthesis of ß-CD/Fe3O4NPs. The properties and characteristics of ß-CD/Fe3O4NPs were investigated using various methods, including ultraviolet-visible (UV/vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetry analysis (TGA), and vibrating-sample magnetometry (VSM). The absorption of ß-CD/Fe3O4NPs caused a distinct peak at 349 nm, as evidenced by the results of UV/vis studies. This peak was attributed to the absorption of surface plasmon resonance. The crystalline nature of ß-CD/Fe3O4NPs was confirmed through XRD analysis. The SEM and TEM analyses have verified the geometry and structural characteristics of ß-CD/Fe3O4NPs. The ß-CD/Fe3O4NPs exhibited remarkable effectiveness in the decomposing efficiency (%) of methylene blue (MB) dye with 52.2, 94.1, and 100% for 0.2, 0.4, and 0.6 g ß-CD/Fe3O4NPs, respectively. In addition, the highest efficiency in hunting radicals was observed (347.2 ± 8.2 mg/g) at 100 mg/mL ß-CD/Fe3O4NPs; the combination of ß-CD/Fe3O4NPs exhibited remarkable effectiveness in inhibiting the growth of some bacteria that cause infections. The capabilities of ß-CD/Fe3O4NPs for various applications showed that these materials could be used in photocatalytic, antioxidants, and antibacterial. Additionally, the eco-friendly synthesis of these materials makes them a promising option for the remediation of harmful pollutants and microbes.

3.
J Agric Food Chem ; 71(30): 11520-11533, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37471325

RESUMO

After an acute intake of 300 g of mango purée by 10 subjects, 0 and 24 h urine and plasma samples were analyzed by high-performance liquid chromatography-high-resolution mass spectrometry. The method was first validated for 44 reference polyphenols in terms of linearity, specificity, limits of detection and quantification, intra-day and inter-day precision, recovery, and matrix effects in two biological matrices. After method validation, a total of 94 microbial-derived phenolic catabolites, including 15 cinnamic acids, 3 phenylhydracrylic acids, 14 phenylpropanoic acids, 12 phenylacetic acids, 28 benzoic acids, 2 mandelic acids, 15 hydroxybenzenes, and 5 hippuric acid derivatives, were identified or tentatively identified in urine and/or plasma. These results establish the value of the UHPLC-HRMS protocol and the use of authentic standards to obtain a detailed and accurate picture of mango polyphenol metabolites, together with their phase II conjugated metabolites, in human bioavailability studies.


Assuntos
Mangifera , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos , Polifenóis/metabolismo , Fenóis/urina
4.
Int J Food Sci Nutr ; 74(4): 532-543, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37369137

RESUMO

Phenolic catabolites excreted by fasting subjects with a functioning colon and ileostomists on a low (poly)phenol diet have been investigated. Urine was collected over a 12 h fasting period after adherence to a low (poly)phenol diet for 36 h. UHPLC-HR-MS quantified 77 phenolics. Some were present in the urine of both groups in similar trace amounts and others were excreted in higher amounts by participants with a colon indicating the involvement of the microbiota. Most were present in sub- or low-µmol amounts, but hippuric acid dominated accounting on average for 60% of the total for both volunteer categories indicating significant production from sources other than non-nutrient dietary (poly)phenols. The potential origins of the phenolics associated with the low (poly)phenol diet, include endogenous catecholamines, surplus tyrosine and phenylalanine, and washout of catabolites derived from pre-study intakes of non-nutrient dietary (poly)phenols.


Assuntos
Microbioma Gastrointestinal , Fenol , Humanos , Catecolaminas , Aminoácidos , Fenóis/metabolismo , Dieta
5.
Free Radic Biol Med ; 199: 34-43, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36764628

RESUMO

The impact of ß-glucan-rich oat bran on the bioavailability of orange juice (OJ) flavanones was investigated. Volunteers consumed 500 mL of OJ with and without 22 g of oat bran containing 6 g of ß-glucan (OB-6). Urine collected 12 h prior to and over a 0-24 h period post-supplementation was analysed by UHPLC-HRMS. Sixteen flavanone metabolites and thirty-nine colon-derived phenolic catabolites were identified and quantified. The major compounds were hesperetin-3'-glucuronide, along with hippuric acids and the C6-C3 phenolic acids 3-(3'-hydroxy-4'-methoxyphenyl)hydracrylic acid and 3-(4'-hydroxy-3'-methoxyphenyl)propanoic acid. A marked reduction in the 0-24 h excretion of flavanone metabolites from 29.7 µmol (9.3% recovery) to 9.3 µmol (2.9% recovery), occurred following consumption of OB-6 compared to OJ. This appeared not to be an effect of fiber on the rate of transport in the upper gut. After consumption of OJ there was a 163 ± 15 µmol excretion of colon-derived phenolic catabolites, equivalent to 43% of (poly)phenol intake and following OB-6 intake there was a further significant 30% increase. The ß-oat bran in OB-6 contained 5.8 µmol of free and 52 µmol of bound phenolic derivatives compared to 371 µmol of OJ (poly)phenols. The elevated excretion of phenolics after OB-6 consumption appears not to be due to bound phenolics in the bran, rather it is consequence, principally, of a bran-mediated increase in the quantities of flavanones passing from the upper to the lower bowel where they were subjected to microbiota-mediated catabolism. CLINICAL TRIAL REGISTRATION NUMBER: This trial was registered at clinicaltrials.gov as NCT04867655.


Assuntos
Citrus sinensis , Flavanonas , Humanos , Avena/metabolismo , Disponibilidade Biológica , Citrus sinensis/metabolismo , Fenóis
6.
Ultrason Sonochem ; 93: 106293, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36638650

RESUMO

A sonochemical based green synthesis method playa powerful role in nanomaterials and composite development. In this work, we developed a perovskite type of strontium titanate via sonochemical process. SrTiO3 particles were incorporated with nitrogen doped graphene oxide through simple ultrasonic irradiation method. The SrTiO3/NGO was characterized by various analytical methods. The nanocomposite of SrTiO3/NGO was modified with laser-induced graphene electrode (LIGE). The SrTiO3/NGO/LIGE was applied for electrochemical sensor towards chemotherapeutic drug detection (nilutamide). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques have been used to examine the electrochemical performance of nilutamide (anti-cancer drug). DPV was found to be more sensitive and found to exhibit a sensitivity 8.627 µA µM-1 cm-2 for SrTiO3/NGO/LIGE with a wide linear range (0.02-892 µM) and low Limit of detection (LOD: 1.16 µM). SrTiO3/NGO/LIGE has been examined for the detection of nilutamide in blood serum and urine samples and obtained a good recovery in the range of 97.2-99.72 %. The enhanced stability and selectivity and practical application results indicates the suitability of SrTiO3/NGO/LIGE towards the detection of nilutamide drug in pharmaceutical industries.


Assuntos
Antineoplásicos , Grafite , Grafite/química , Técnicas Eletroquímicas/métodos , Eletrodos
7.
Mol Aspects Med ; 89: 101107, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35931563

RESUMO

Understanding the fate of ingested polyphenols is crucial in elucidating the molecular mechanisms underlying the beneficial effects of a fruit and vegetable-based diet. This review focuses on the colon microbiota-mediated transformation of the flavan-3-ols and the structurally related procyanidins found in dietary plant foods and beverages, plus the flavan-3-ol-derived theaflavins of black tea, and the post-absorption phase II metabolism of the gut microbiota catabolites. Despite significant advances in the last decade major analytical challenges remain. Strategies to address them are presented.


Assuntos
Flavonoides , Polifenóis , Humanos , Flavonoides/metabolismo , Polifenóis/metabolismo , Colo/metabolismo , Dieta
8.
Membranes (Basel) ; 12(5)2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35629862

RESUMO

Healthcare textiles are gaining great attention in the textile industry. Electrospun nanofibers are considered the golden soldiers due to their strength, flexibility, and eco-friendly properties. The present study aimed to evaluate the potency of polyvinyl alcohol (PVA) nanofibers loaded with newly biosynthesized silver nanoparticles (Ag-NPs) as a wound healing dressing. Chocolate-band snail (Eobania vermiculata) mucus (which is part of the Mollusca defense system) was used as a novel reducing and stabilizing agent. Data indicated the effectiveness of Eobania vermiculata's mucus in silver nanoparticle synthesis after a 24 h incubation time. The biosynthesized AgNPs-SM showed a 13.15 nm particle size, -22.5 mV ζ potential, and 0.37 PDI, which proved the stability of the synthesized nanoparticles. Eobania vermiculata mucus and AgNPs-SM showed potent antibacterial activity, especially against Pseudomonas aeruginosa. The electrospinning technique was applied in the fabrication of PVA/AgNPs-SM nanofibers, which were homogenous with a fine diameter of about 100-170 nm and showed a significantly high antimicrobial activity. In vitro and in vivo studies revealed that PVA/AgNPs-SM nanofibers were safe and efficiently enhanced the wound healing process (typical histological picture of the proliferative phase with compact and well aligned collagen fibers in the dermal tissue after 12 days) together with bacterial growth inhibition in the infected skin area.

9.
Int J Biol Macromol ; 210: 208-217, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35489625

RESUMO

The polysaccharide pectin (PC) was functionalized with the photo-responsive cinnamic acid hydrazide (CN) to produce the photo-crosslinkable PC-CN hydrogel material that was then evaluated as a carrier for encapsulation of the drug model aspirin. Cinnamic acid hydrazide was first prepared and then incorporated with the abundant -COOCH3 groups on the pectin chain via hydrazide linkage. The obtained polymeric derivatives have been characterized by means of instrumental techniques including FTIR and NMR. The obtained PC-CN hydrogels with different cinnamic functionality were also freeze-dried and examined by SEM, which indicated more coherent hydrogel texture by increasing the cinnamic functionalization. The effect of the photo-curing time, as well as the functionalization degree, on the swelling and gelation of the obtained hydrogel was also studied to evaluate the potential of the developed material in drug delivery systems using aspirin as a common and available drug model. The developed PC-CN hydrogel materials exhibited high potential as a drug carrier that enables the control of the drug release via optimizing both the degree of cinnamic functionality and the photo-curing time.


Assuntos
Hidrogéis , Pectinas , Aspirina , Cinamatos , Hidrazinas , Hidrogéis/química
10.
Molecules ; 27(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35408644

RESUMO

Nitrogen-containing atoms in their core structures have been exclusive building blocks in drug discovery and development. One of the most significant and well-known heterocycles is the 1,3,4-thidiazole nucleus, which is found in a wide range of natural products and therapeutic agents. In the present work, certain tris-1,3,4-thiadiazole derivatives (6, 7) were synthesized through a multi-step synthesis approach. All synthesized compounds were characterized using different spectroscopic tools. Previously, thiadiazole compounds as anti-Toxoplasma gondii agents have been conducted and reported in vitro. However, this is the first study to test the anti-Toxoplasma gondii activity of manufactured molecular hybrids thiadiazole in an infected mouse model with the acute RH strain of T. gondii. All the observed results demonstrated compound (7)'s powerful activity, with a considerable reduction in the parasite count reaching 82.6% in brain tissues, followed by liver and spleen tissues (65.35 and 64.81%, respectively). Inflammatory and anti-inflammatory cytokines assessments proved that Compound 7 possesses potent antiparasitic effect. Furthermore, docking tests against TgCDPK1 and ROP18 kinase (two major enzymes involved in parasite invasion and egression) demonstrated compound 7's higher potency compared to compound 6 and megazol. According to the mentioned results, tris-1,3,4-thiadiazole derivatives under test can be employed as potent antiparasitic agents against the acute RH strain of T. gondii.


Assuntos
Anti-Infecciosos , Tiadiazóis , Toxoplasma , Animais , Anti-Infecciosos/farmacologia , Antiparasitários/farmacologia , Camundongos , Baço , Tiadiazóis/farmacologia
11.
Int J Food Sci Nutr ; 73(4): 531-537, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34933644

RESUMO

The impact of ß-glucan on the bioavailability of orange juice (OJ) flavanones was investigated in a randomised controlled trial. Volunteers consumed 500 mL of OJ without or with either 3 g (OB-3) or 6 g (OB-6) of ß-glucan. Urine samples, collected 12 h before and over a 0-24 h period post-supplementation, were analysed by high-performance liquid chromatography-high resolution mass spectrometry. The overall 0-24 h urinary excretion of the 17 flavanone metabolites identified and quantified in urine after OJ ingestion corresponded to 29.7 µmol, and 25.0 and 9.3 µmol, respectively, after OB-3 and OB-6 intake. This corresponds to 9.3, 7.9, and 2.9% recoveries of the 318 µmol of the ingested flavanones. The acute ingestion of OJ with 6 g, but not 3 g of ß-glucan led to a significant reduction (p < 0.05) in the excretion of flavanone metabolites compared with consumption of OJ alone.


Assuntos
Citrus sinensis , Flavanonas , Hesperidina , beta-Glucanas , Bebidas/análise , Disponibilidade Biológica , Citrus sinensis/química , Flavanonas/análise , Hesperidina/análise , Humanos
12.
Eur J Med Chem ; 226: 113875, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34634741

RESUMO

The first structural analysis comparing the binding mode to the target carbonic anhydrases (CAs, EC 4.2.1.1) of two opposite classes of modulators is presented here: coumarin derivatives act as prodrug CA inhibitors (CAIs), being hydrolyzed by the enzyme esterase activity to 2-hydroxycinnamic acids that occlude the active site entrance; CA activators (CAAs) belonging of the amine and amino acid types, enhance the CA activity by increasing the efficiency of the rate-determining proton shuttling step in the CA catalytic cycle. Analysis of the crystallographic data available for the human CA isoform II in adduct with two coumarin CAIs and some CAAs showed that both types of CA modulators bind in the same region of the enzyme active site, basically interacting with superimposable amino acid residues, that are Trp5, Asn62, His64, Asn67, Gln92, Thr200. A plethora of water molecules also participate in the adducts formation. This structural analysis showed that presence of certain chemical groups in the compound structure is mandatory to produce an activating rather than inhibitory action, such as multiple nitrogen- and oxygen-based moieties capable of shuttling protons or forming extended H-bond networks nearby the proton shuttle residue. This constitutes the only known example among all enzymes of an identical binding site for inhibitors and activators, which, in addition, possess significant pharmacological applications.


Assuntos
Aminas/farmacologia , Aminoácidos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Cumarínicos/farmacologia , Aminas/química , Aminoácidos/química , Sítios de Ligação/efeitos dos fármacos , Inibidores da Anidrase Carbônica/química , Cumarínicos/química , Humanos , Estrutura Molecular
13.
J Phys Chem Lett ; 12(10): 2528-2535, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33683137

RESUMO

Low-dimensional metal halide perovskites are being intensively investigated because of their higher stability and chemical versatility in comparison to their 3D counterparts. Unfortunately, this comes at the expense of the electronic and charge transport properties, limited by the reduced perovskite dimensionality. Cation engineering can be envisaged as a solution to tune and possibly further improve the material's optoelectronic properties. In this work, we screen and design new electronically active A-site cations that can promote charge transport across the inorganic layers. We show that hybridization of the valence band electronic states of the perovskite inorganic sublattice and the highest occupied molecular orbitals of the A-site organic cations can be tuned to exhibit a variety of optoelectronic properties. A significant interplay of A-cation size, electronic structure, and steric constraints is revealed, suggesting intriguing means of further tuning the 2D perovskite electronic structure toward achieving stable and efficient solar cell devices.

14.
Nanomaterials (Basel) ; 9(12)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810331

RESUMO

In this work, new smart mesoporous amine-functionalized silica nanoparticles were prepared from hydrolyzing microgels based on N-isopropyl acrylamide-co-vinyltrimethoxysilane microgels with tetraethoxysilicate and 3-aminopropyltriethoxysilane by sol-gel method. The thermal stability and Fourier transform infrared were used to determine the amine contents of the silica nanoparticles. The pH sensitivity of the synthesized silica nanoparticles in their aqueous solutions was evaluated by using dynamic light scattering (DLS) and zeta potential measurements. The porosity of the amine-functionalized silica nanoparticles was evaluated from a transmittance electron microscope and Brunauer-Emmett-Teller (BET) plot. The results have positively recommended the pH-sensitive amine-functionalized silica nanoparticles as one of the effective nano-adsorbent to remove 313 mg·g-1 of CB-R250 water pollutant.

15.
ACS Omega ; 4(25): 21288-21301, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31867523

RESUMO

New magnetic silica imidazolium ionic liquid nanocomposites were synthesized by a sol-gel technique. The (3-aminopropyl)triethoxysilane (APTS) was condensed with glyoxal and p-hydroxybenzaldehyde in acetic acid to produce an amino-modified silica ionic liquid (Si-IIL). The APTS was condensed with TEOS in ethanol and water to prepare amino-modified SiO2 nanoparticles. The produced amino-modified SiO2 silica was condensed with glyoxal and p-hydroxybenzaldehyde in acetic acid to produce chemically bonded silica SiO2-IIL. The SiO2-IIL and Si-IIL were used as capping agents during and after the formation of magnetite nanoparticles in ammonia to produce magnetic SiO2-IIL-Fe3O4 and Fe3O4-Si-IIL adsorbents, respectively. Their chemical structure, morphology, crystalline lattice structure, surface charges, particle sizes, and magnetic characteristics elucidated the formation of core-shell and highly dispersed magnetic nanocomposites. The saturation magnetization values of Fe3O4-Si-IIL and SiO2-IIL-Fe3O4 were 35.3 and 30.8, respectively. The uniform dispersed disconnected spherical morphologies appeared for Fe3O4-Si-IIL hybrid and the core-shell spherical morphology obtained with SiO2-IIL-Fe3O4 hybrid NPs. The Fe3O4-Si-IIL and SiO2-IIL-Fe3O4 show an excellent high chemical adsorption capacities as 460.3 and 300.9 mg·g-1, respectively (not reported in the literature) when used as an adsorbent to remove CB-R250 water pollutant under optimum conditions. Their applicability and reusability as fast and highly effective adsorbents for Coomassie blue (CB-R250) organic water pollutants were investigated.

16.
ACS Omega ; 4(25): 21395-21409, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31867534

RESUMO

Amphiphilic smart gels of different sizes (macro, micro, and nano) are widely used in advanced medical, industrial, and environmental applications. They are sensitive, responsive to different environments, and possess a high surface activity to adsorb onto different interfaces. In this study, new amphiphilic alkoxysilane-containing microgels, hybrid polysiloxane microgel, and silica nanoparticles were prepared using a cross-linking surfactant-free cross-linking polymerization technique for N-isopropylacrylamide (NIPAm) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) monomers. Vinyltrimethoxysilane (VTS) was used as a silane precursor in the cross-linking polymerization to hydrolyze with tetraethoxysilane (TEOS) in ammonia using an emulsion technique, to create polysiloxane microgel and silica nanoparticles. The surface activity measurements confirmed that NIPAm/VTS had a higher surface activity than NIPAm/AMPS-VTS microgels and their hybrid polysiloxane microgel owing to the differences of the cross-linking of microgels from the center to the microgel periphery, which alter their morphologies.

17.
J Colloid Interface Sci ; 552: 312-318, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31132633

RESUMO

The electrochemical nitrogen reduction reaction (NRR) under mild conditions is significantly challenging, due to the extremely high stability of dinitrogen (N2) molecules. The NRR pathway also confronts the competitive water reduction reaction that takes places universally in an aqueous solution. Herein, a Fe2O3/Cu catalyst is demonstrated as an efficient NRR electrocatalyst. The electronic interactions elevate the d-state electron center, enabling strong back-bonding for N2 molecules. The altering of d-electron distribution promotes the adsorption of N2, leading to a high catalytic activity. As a result, the Fe2O3/Cu catalyst exhibits an outstanding ammonia production rate of 15.66 µg·h-1·mgcat.-1 at -0.1 V versus reversible hydrogen electrode (RHE), a Faradaic efficiency of 24.4%, and a good electrochemical stability.

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