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1.
Chembiochem ; 25(8): e202300862, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38369609

RESUMO

A Morita-Baylis-Hillman Adduct (MBHA) derivative bearing a triphenylamine moiety was found to react with human serum albumin (HSA) shifting its emission from the blue to the green-yellow thus leading to green fluorescent albumin (GFA) derivatives and enlarging the platform of probes for aggregation-induced fluorescent-based detection techniques. A possible interaction of MBHA derivative 7 with a lipophilic pocket within the HSA structure was suggested by docking studies. DLS experiments showed that the reaction with HSA induce a conformational change of the protein contributing to the aggregation process of GFA derivatives. The results of investigations on the biological properties suggested that GFA retained the ability of binding drug molecules such as warfarin and diazepam. Finally, cytotoxicity evaluation studies suggested that, although the MBHA derivative 7 at 0.1 µg/mL affected the percentage of cell viability in comparison to the negative control, it cannot be considered cytotoxic, whereas at all the other concentrations≥0.5 µg/mL resulted cytotoxic at different extent.


Assuntos
Albumina Sérica Humana , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas/metabolismo , Albumina Sérica Humana/química , Espectrometria de Fluorescência
2.
Int J Mol Sci ; 24(2)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36674712

RESUMO

Liposomes have been successfully used as drug-delivery vehicles, but there are no clinical studies on improved fertility and the few reported experimental studies have been performed in animal models far from humans. The aim of this paper was to study the effects of treatment with cationic, anionic and zwitterionic liposomes on our superior mammalian model of porcine prepubertal Sertoli cells (SCs) to find a carrier of in vitro test drugs for SCs. Porcine pre-pubertal SCs cultures were incubated with different liposomes. Viability, apoptosis/necrosis status (Annexin-V/Propidium iodide assay), immunolocalisation of ß-actin, vimentin, the phosphorylated form of AMP-activated protein Kinase (AMPK)α and cell ultrastructure (Transmission Electron Microscopy, TEM) were analysed. Zwitterionic liposomes did not determine changes in the cell cytoplasm. The incubation with anionic and cationic liposomes modified the distribution of actin and vimentin filaments and increased the levels of the phosphorylated form of AMPKα. The Annexin/Propidium Iodide assay suggested an increase in apoptosis. TEM analysis highlighted a cytoplasmic vacuolisation. In conclusion, these preliminary data indicated that zwitterionic liposomes were the best carrier to use in an in vitro study of SCs to understand the effects of molecules or drugs that could have a clinical application in the treatment of certain forms of male infertility.


Assuntos
Lipossomos , Células de Sertoli , Humanos , Masculino , Animais , Suínos , Lipossomos/química , Vimentina , Células de Sertoli/metabolismo , Propídio , Apoptose , Mamíferos/metabolismo
3.
Int J Mol Sci ; 24(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069187

RESUMO

Glaucoma represents a group of neurodegenerative diseases characterized by optic nerve damage and the slowly progressive death of retinal ganglion cells. Glaucoma is considered the second leading cause of irreversible blindness worldwide. Pharmaceutical treatment of glaucoma is critical because of the properties of the ocular barrier that limit the penetration of drugs, resulting in lower systemic bioavailability. This behavior causes the need of frequent drug administration, which leads to deposition of concentrated solutions on the eye, causing toxic effects and cellular damage to the eye. To overcome these drawbacks, novel drug-delivery systems, such as liposomes, can play an important role in improving the therapeutic efficacy of antiglaucomatous drugs. In this work, liposomes were synthesized to improve various aspects, such as ocular barrier penetration, bioavailability, sustained release of the drug, targeting of the tissue, and reduction in intraocular pressure. Citicoline (CDP-choline; cytidine 5'-diphosphocholine) is an important intermediate in the biosynthesis of cell membrane phospholipids, with neuroprotective and neuroenhancement properties, and it was used in the treatment on retinal function and neural conduction in the visual pathways of glaucoma patients. In this study, citicoline was loaded into the 1,2-dioleoyl-sn-glycerol-3-phosphocholine and cholesterol liposomal carrier to enhance its therapeutic effect. The citicoline encapsulation efficiency, drug release, and size analysis of the different liposome systems were investigated using dynamic light scattering, nuclear magnetic resonance, infrared spectroscopy, and ToF-SIMS experiments.


Assuntos
Glaucoma , Lipossomos , Humanos , Lipossomos/uso terapêutico , Citidina Difosfato Colina/uso terapêutico , Sistemas de Liberação de Medicamentos , Glaucoma/tratamento farmacológico , Glaucoma/metabolismo , Retina/metabolismo
4.
Molecules ; 28(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37570717

RESUMO

Principles of quality by design and design of experiments are acquiring more importance in the discovery and application of new drug carriers, such as solid lipid nanoparticles. In this work, an optimized synthesis of solid lipid nanoparticles loaded with Triamcinolone Acetonide is presented using an approach that involves Stearic Acid as a lipid, soy PC as an ionic surfactant, and Tween 80 as a nonionic surfactant. The constructed circumscribed Central Composite Design considers the lipid and nonionic surfactant quantities and the sonication amplitude in order to optimize particle size and Zeta potential, both measured by means of Dynamic Light Scattering, while the separation of unentrapped drug from the optimized Triamcinolone Acetonide-loaded solid lipid nanoparticles formulation is performed by Size Exclusion Chromatography and, subsequently, the encapsulation efficiency is determined by HPLC-DAD. The proposed optimized formulation-with the goal of maximizing Zeta potential and minimizing particle size-has shown good accordance with predicted values of Zeta potential and dimensions, as well as a high value of encapsulated Triamcinolone Acetonide. Experimental values obtained from the optimized synthesis reports a dimension of 683 ± 5 nm, which differs by 3% from the predicted value, and a Zeta potential of -38.0 ± 7.6 mV (12% difference from the predicted value).


Assuntos
Nanopartículas , Triancinolona Acetonida , Triancinolona Acetonida/química , Nanopartículas/química , Portadores de Fármacos/química , Tamanho da Partícula , Tensoativos/química
5.
Chemistry ; 28(50): e202201477, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-35695822

RESUMO

HBDI-like chromophores represent a novel set of biomimetic switches mimicking the fluorophore of the green fluorescent protein that are currently studied with the hope to expand the molecular switch/motor toolbox. However, until now members capable of absorbing visible light in their neutral (i. e. non-anionic) form have not been reported. In this contribution we report the preparation of an HBDI-like chromophore based on a 3-phenylbenzofulvene scaffold capable of absorbing blue light and photoisomerizing on the picosecond timescale. More specifically, we show that double-bond photoisomerization occurs in both the E-to-Z and Z-to-E directions and that these can be controlled by irradiating with blue and UV light, respectively. Finally, as a preliminary applicative result, we report the incorporation of the chromophore in an amphiphilic molecule and demonstrate the formation of a visible-light-sensitive nanoaggregated state in water.


Assuntos
Luz , Proteínas de Fluorescência Verde/química
6.
Molecules ; 26(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34063803

RESUMO

The intake of tomato glycoalkaloids can exert beneficial effects on human health. For this reason, methods for a rapid quantification of these compounds are required. Most of the methods for α-tomatine and dehydrotomatine quantification are based on chromatographic techniques. However, these techniques require complex and time-consuming sample pre-treatments. In this work, HPLC-ESI-QqQ-MS/MS was used as reference method. Subsequently, multiple linear regression (MLR) and partial least squares regression (PLSR) were employed to create two calibration models for the prediction of the tomatine content from thermogravimetric (TGA) and attenuated total reflectance (ATR) infrared spectroscopy (IR) analyses. These two fast techniques were proven to be suitable and effective in alkaloid quantification (R2 = 0.998 and 0.840, respectively), achieving low errors (0.11 and 0.27%, respectively) with the reference technique.


Assuntos
Modelos Químicos , Solanum lycopersicum/química , Tomatina/análogos & derivados , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Análise Multivariada , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Infravermelho/métodos , Espectrometria de Massas em Tandem/métodos , Termogravimetria/métodos , Tomatina/análise
7.
Molecules ; 26(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34299402

RESUMO

Prunus persica L. is one of the most important fruit crops in European production, after grapes, apples, oranges and watermelons. Most varieties are rich in secondary metabolites, showing antioxidant properties for human health. The purpose of this study was to develop a chemical analysis methodology, which involves the use of different analytical-instrumental techniques to deepen the knowledge related to the profile of metabolites present in selected cultivars of peaches and nectarines cultivated in the Mediterranean area (Southern Italy). The comparative study was conducted by choosing yellow-fleshed peaches (RomeStar, ZeeLady) and yellow-fleshed nectarines (Nectaross, Venus) from two geographical areas (Piana di Sibari and Piana di Metaponto), and by determining the chemical parameters for the flesh and skin that allow for identification of any distinctive varietal and/or geographical characteristics. A combined analytical and chemometric approach was used, trough rheological, thermogravimetric (TGA), chromatographic (HPLC-ESI-MS), spectroscopic (UV-Vis, ATR-FTIR, NMR) and spectrometric (ToF-SIMS) analysis. This approach allowed us to identify the characterizing parameters for the analysis of a plant matrix so that the developed methodology could define an easily exportable and extendable model for the characterization of other types of vegetable matrices.


Assuntos
Antioxidantes/análise , Frutas/classificação , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Modelos Estatísticos , Prunus persica/classificação , Prunus persica/metabolismo , Antioxidantes/metabolismo , Geografia
8.
Molecules ; 25(16)2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32824747

RESUMO

Blood pressure control in hypertensive subjects calls for changes in lifestyle, especially diet. Tomato is widely consumed and rich in healthy components (i.e., carotenoids, vitamins and polyphenols). The aim of this study was to evaluate the chemical composition and antihypertensive effects of locular gel reconstituted in serum of green tomatoes of "Camone" variety. Tomato serum and locular gel were chemically characterised. The antihypertensive effects of the locular gel in serum, pure tomatine, and captopril, administered by oral gavage, were investigated for 4 weeks in male spontaneously hypertensive and normotensive rats. Systolic blood pressure and heart rate were monitored using the tail cuff method. Body and heart weight, serum glucose, triglycerides and inflammatory cytokines, aorta thickness and liver metabolising activity were also assessed. Locular gel and serum showed good tomatine and polyphenols content. Significant reductions in blood pressure and heart rate, as well as in inflammatory blood cytokines and aorta thickness, were observed in spontaneously hypertensive rats treated both with locular gel in serum and captopril. No significant effects were observed in normotensive rats. Green tomatoes locular gel and serum, usually discarded during tomato industrial processing, are rich in bioactive compounds (i.e., chlorogenic acid, caffeic acid and rutin, as well as the glycoalkaloids, α-tomatine and dehydrotomatine) that can lower in vivo blood pressure towards healthier values, as observed in spontaneously hypertensive rats.


Assuntos
Anti-Hipertensivos/farmacologia , Géis/química , Hipertensão/tratamento farmacológico , Extratos Vegetais/farmacologia , Solanum lycopersicum/química , Solanum lycopersicum/classificação , Animais , Pressão Sanguínea , Frequência Cardíaca , Masculino , Ratos , Ratos Endogâmicos SHR
9.
Int J Mol Sci ; 20(6)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884846

RESUMO

Research on microcirculatory alterations in human heart disease is essential to understand the genesis of myocardial contractile dysfunction and its evolution towards heart failure. The use of contrast agents in magnetic resonance imaging is an important tool in medical diagnostics related to this dysfunction. Contrast agents significantly improve the imaging by enhancing the nuclear magnetic relaxation rates of water protons in the tissues where they are distributed. Gadolinium complexes are widely employed in clinical practice due to their high magnetic moment and relatively long electronic relaxation time. In this study, the behavior of gadolinium ion as a contrast agent was investigated by two complementary methods, relaxometry and secondary ion mass spectrometry. The study examined the distribution of blood flow within the microvascular network in ex vivo Langendorff isolated rat heart models, perfused with Omniscan® contrast agent. The combined use of secondary ion mass spectrometry and relaxometry allowed for both a qualitative mapping of agent distribution as well as the quantification of gadolinium ion concentration and persistence. This combination of a chemical mapping and temporal analysis of the molar concentration of gadolinium ion in heart tissue allows for new insights on the biomolecular mechanisms underlying the microcirculatory alterations in heart disease.


Assuntos
Gadolínio/administração & dosagem , Insuficiência Cardíaca/diagnóstico por imagem , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética , Animais , Meios de Contraste/administração & dosagem , Coração/efeitos dos fármacos , Insuficiência Cardíaca/patologia , Humanos , Microcirculação/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Contração Miocárdica/fisiologia , Ratos , Espectrometria de Massa de Íon Secundário , Água/química
10.
Molecules ; 24(6)2019 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-30884870

RESUMO

In this study, we developed and validated a new proposed parameter quantifying the interaction strength between natural and/or synthetic molecules with paramagnetic metal ions. The Metal ion Recognition Index, Miri, is a quantitative parameter to describe the proton environment and to define their involvement in the inner and/or outer sphere of the paramagnetic metal ion. The method is based on the analysis of NMR proton spin-lattice relaxation rates of a specific ligand in both the diamagnetic and paramagnetic conditions. The proposed procedure is also useful to calculate the ligand proton spin-lattice relaxation rate in the paramagnetic bound conditions, which is typically very difficult to determine experimentally. Miri was used to compare the ligand proton involvement toward different paramagnetic species, in particular the Copper(II)-Piroxicam system. Copper(II)-Piroxicam complex is one of the most active anti-inflammatory and anti-arthritic species. Miri provides an opportunity to improve our knowledge of metal-ligand complexes that play a fundamental role in bioinorganic interactions.


Assuntos
Complexos de Coordenação/química , Íons/química , Metais/química , Piroxicam/química , Cobre/química , Espectroscopia de Ressonância de Spin Eletrônica , Ligantes , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Manganês/química , Prótons
11.
Molecules ; 23(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441832

RESUMO

Samples of sweet and dessert wines, Vin Santo (VSR) from Malvasia grapes, and Granello (GR) from Sauvignon grapes were collected and analyzed for the content of selected macro- and micro-nutrients (Na, K, Mg, Ca, Mn, Fe, Cu and Zn) and of Pb. GR wines had low levels for Fe, Cu and Zn, when compared to VSR and in particular Zn was two orders of magnitude lower. Methods to decrease the content of Zn and Cu in VSR, as well as those for reducing, at the same time, the concentrations of Ca, Mg and K in both VSR and GR, to avoid the formation of opalescence and depots of metal tartrates, were studied. Synthetic hydrogels containing l-histidine residue were tested. The overall relative lowering effects were by ca 4, 23, and 12% for K, Mg and Ca contents, and ca 6, 27 and 10%, for Mn, Cu and Zn contents, in GR wine samples. Commercial ion exchange resin Lanxess Lewatit L-207 and L-208 were then assayed, being legally allowed in the agro-food industry. The L-207 resin revealed great lowering effects on the concentrations of Mn, Cu and Zn, being 75, 91 and 97%, respectively, in VSR wines and 77, 76 and 92%, respectively, in GR wines. The content of Zn was reduced from 49.3 ± 1.2 mg/L in the original wine, down to 1.1 ± 0.1 mg/L, within 48 h soaking. The effects on the character of the dessert wines by the resin L-207 was also taken under control, measuring pH and color index. The color index changed by ca 15% and pH by ca 6% upon treatment of VSR wine with L-207 resins (48 h).


Assuntos
Hidrogéis/química , Resinas de Troca Iônica/química , Íons/química , Metais/química , Vinho/análise , Adsorção , Hidrogéis/síntese química , Concentração de Íons de Hidrogênio , Pigmentação
12.
Biochim Biophys Acta Gen Subj ; 1861(4): 860-870, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28095317

RESUMO

BACKGROUND: Liposomes, used to improve the therapeutic index of new and established drugs, have advanced with the insertion of active targeting. The lectin from Lotus tetragonolobus (LTL), which binds glycans containing alpha-1,2-linked fucose, reveals surface regionalized glycoepitopes in highly proliferative cells not detectable in normally growing cells. In contrast, other lectins localize the corresponding glycoepitopes all over the cell surface. LTL also proved able to penetrate the cells by an unconventional uptake mechanism. METHODS: We used confocal laser microscopy to detect and localize LTL-positive glycoepitopes and lectin uptake in two cancer cell lines. We then constructed doxorubicin-loaded liposomes functionalized with LTL. Intracellular delivery of the drug was determined in vitro and in vivo by confocal and electron microscopy. RESULTS: We confirmed the specific localization of Lotus binding sites and the lectin uptake mechanism in the two cell lines and determined that LTL-functionalized liposomes loaded with doxorubicin greatly increased intracellular delivery of the drug, compared to unmodified doxorubicin-loaded liposomes. The LTL-Dox-L mechanism of entry and drug delivery was different to that of Dox-L and other liposomal preparations. LTL-Dox-L entered the cells one by one in tiny tubules that never fused with lysosomes. LTL-Dox-L injected in mice with melanoma specifically delivered loaded Dox to the cytoplasm of tumor cells. CONCLUSIONS: Liposome functionalization with LTL promises to broaden the therapeutic potential of liposomal doxorubicin treatment, decreasing non-specific toxicity. GENERAL SIGNIFICANCE: Doxorubicin-LTL functionalized liposomes promise to be useful in the development of new cancer chemotherapy protocols.


Assuntos
Proliferação de Células/efeitos dos fármacos , Fabaceae/metabolismo , Lectinas/administração & dosagem , Lectinas/química , Lipossomos/administração & dosagem , Lipossomos/química , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Citoplasma/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Epitopos/administração & dosagem , Epitopos/química , Humanos , Lisossomos/efeitos dos fármacos , Melanoma Experimental/tratamento farmacológico , Camundongos
13.
Cells ; 13(6)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38534386

RESUMO

Semen handling and cryopreservation induce oxidative stress that should be minimized. In this study, human semen was supplemented during cryopreservation with formulations of handmade liposomes and chlorogenic acid (CGA), an antioxidant compound. Zwitterionic (ZL), anionic (AL), and cationic (CL) liposomes were synthesized and characterized. Three aliquots of swim-up-selected sperm were incubated with ZL, AL, and CL (1:10,000), respectively. The percentages of sperm with progressive motility, high mitochondrial membrane potential (MMP; JC-1), double-stranded DNA (dsDNA acridine orange), and acrosome integrity (Pisum sativum agglutinin) were assessed. Then, human semen was frozen using both 1:10,000 ZL and CGA as follows: freezing medium/empty ZL (EL), freezing medium/empty ZL/CGA in the medium (CGA + EL), freezing medium/CGA loaded ZL (CGA), freezing medium (CTR). The same sperm endpoints were evaluated. ZL were the most tolerated and used for semen cryopreservation protocols. All the supplemented samples showed better endpoints versus CTR (p < 0.001). In particular, spermatozoa from the CGA and CGA + EL A samples showed increased motility, dsDNA, and acrosome integrity versus CTR and EL (p < 0.001; motility EL vs. CGA + EL p < 0.05). ZL and CGA can improve post-thaw sperm quality, acting on both cold shock effect management and oxidative stress. These findings open new perspectives on human and animal reproduction.


Assuntos
Preservação da Fertilidade , Preservação do Sêmen , Animais , Humanos , Masculino , Congelamento , Ácido Clorogênico/farmacologia , Lipossomos , Crioprotetores/farmacologia , Preservação do Sêmen/métodos , Sementes , Espermatozoides , Criopreservação/métodos , Suplementos Nutricionais
14.
Gels ; 10(2)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38391421

RESUMO

An easy and viable crosslinking technology, based on the "click-chemistry" reaction copper(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (click-crosslinking), was applied to graft copolymers of medium molecular weight (i.e., 270 kDa) hyaluronic acid (HA) grafted with ferulic acid (FA) residues bearing clickable propargyl groups, as well as caffeic acid derivatives bearing azido-terminated oligo(ethylene glycol) side chains. The obtained crosslinked materials were characterized from the point of view of their structure and aggregation liability to form hydrogels in a water environment. The most promising materials showed interesting loading capability regarding the antioxidant agent phycocyanin (PC). Two novel materials complexes (namely HA(270)-FA-TEGEC-CL-20/PC and HA(270)-FA-HEGEC-CL-20/PC) were obtained with a drug-to-material ratio of 1:2 (w/w). Zeta potential measurements of the new complexes (-1.23 mV for HA(270)-FA-TEGEC-CL-20/PC and -1.73 mV for HA(270)-FA-HEGEC-CL-20/PC) showed alterations compared to the zeta potential values of the materials on their own, suggesting the achievement of drug-material interactions. According to the in vitro dissolution studies carried out in different conditions, novel drug delivery systems (DDSs) were obtained with a variety of characteristics depending on the desired route of administration and, consequently, on the pH of the surrounding environment, thanks to the complexation of phycocyanin with these two new crosslinked materials. Both complexes showed excellent potential for providing a controlled/prolonged release of the active pharmaceutical ingredient (API). They also increased the amount of drug that reach the target location, enabling pH-dependent release. Importantly, as demonstrated by the DPPH free radical scavenging assay, the complexation process, involving freezing and freeze-drying, showed no adverse effects on the antioxidant activity of phycocyanin. This activity was preserved in the two novel materials and followed a concentration-dependent pattern similar to pure PC.

15.
Nanomaterials (Basel) ; 14(8)2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38668220

RESUMO

Natamycin is a tetraene polyene that exploits its antifungal properties by irreversibly binding components of fungal cell walls, blocking the growth of infections. However, topical ocular treatments with natamycin require frequent application due to the low ability of this molecule to permeate the ocular membrane. This limitation has limited the use of natamycin as an antimycotic drug, despite it being one of the most powerful known antimycotic agents. In this work, different lipidic nanoformulations consisting of transethosomes or lipid nanoparticles containing natamycin are proposed as carriers for optical topical administration. Size, stability and zeta potential were characterized via dynamic light scattering, the supramolecular structure was investigated via small- and wide-angle X-ray scattering and 1H-NMR, and the encapsulation efficiencies of the four proposed formulations were determined via HPLC-DAD.

16.
ScientificWorldJournal ; 2013: 138916, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23766672

RESUMO

Water-protein interactions help to maintain flexible conformation conditions which are required for multifunctional protein recognition processes. The intimate relationship between the protein surface and hydration water can be analyzed by studying experimental water properties measured in protein systems in solution. In particular, proteins in solution modify the structure and the dynamics of the bulk water at the solute-solvent interface. The ordering effects of proteins on hydration water are extended for several angstroms. In this paper we propose a method for analyzing the dynamical properties of the water molecules present in the hydration shells of proteins. The approach is based on the analysis of the effects of protein-solvent interactions on water protons NMR relaxation parameters. NMR relaxation parameters, especially the nonselective (R1(NS)) and selective (R1(SE)) spin-lattice relaxation rates of water protons, are useful for investigating the solvent dynamics at the macromolecule-solvent interfaces as well as the perturbation effects caused by the water-macromolecule interactions on the solvent dynamical properties. In this paper we demonstrate that Nuclear Magnetic Resonance Spectroscopy can be used to determine the dynamical contributions of proteins to the water molecules belonging to their hydration shells.


Assuntos
Modelos Químicos , Modelos Moleculares , Proteínas/química , Proteínas/ultraestrutura , Água/química , Sítios de Ligação , Simulação por Computador , Ligação Proteica , Mapeamento de Interação de Proteínas/métodos
17.
Polymers (Basel) ; 15(22)2023 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-38006179

RESUMO

The UN 2030 Agenda for Sustainable Development established the goal of cutting the use of pesticides in the EU by 50% by 2030. However, a ban on pesticides could seriously affect the productivity of agriculture, resulting in severe issues due to global hunger and food deficiency. Controlled release (CR) of bioactive chemicals could play a valid alternative in this context. To this aim, two biodegradable polymers, namely sodium alginate (AL) and sodium carboxymethylcellulose (CMC), were employed to obtain crosslinked hydrogel beads for the encapsulation and CR of glycoalkaloids extracted from tomato and potato leaves to be used as biocompatible disinfectants for agricultural soils. The physico-chemical characterization of the controlled-release systems was carried out by means of Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, Scanning Electron Microscopy (SEM), thermogravimetry (TGA), differential scanning calorimetry (DSC) (FWI > 80%) and drying kinetics. The plant extracts and the encapsulation efficiency (~84%) were, respectively, characterized and evaluated by High-performance Liquid Chromatography-Mass Spectrometry (HPLC-MS). Finally, preliminary microbiological tests were conducted to test the efficacy of the most promising systems as biocidal formulations both in the lab and on a model soil, and interesting results were obtained in the reduction of bacterial and fungal load, which could lead to sustainable perspectives in the field.

18.
RSC Adv ; 13(51): 35773-35780, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38090072

RESUMO

A Morita-Baylis-Hillman acetate was dimerized by a click-chemistry Copper(i)-Catalysed Azide-Alkyne Cycloaddition (CuAAC) reaction employing a tri(ethylene glycol) diazide derivative to obtain a dimeric MBHA derivative. The reaction of this dimeric MBHA derivative with n-butylamine afforded a photoisomerizable macrocyclic crown ether-paracyclophane hybrid architecture that is potentially useful in a large variety of applications as well as those already well-known for crown ethers.

19.
Foods ; 11(11)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35681346

RESUMO

Consumption of cereals (and particularly ancient cereals) is considered the base of a healthy diet, and all current dietary guidelines have cereals at the bottom of the nutrition pyramid. Together with cereals, legumes are an excellent source of nutrients and nutraceuticals. The effects of agroindustrial pretreatments (flaking and precooking processes) on the antioxidant potential of flours from ancient cereals and legumes were studied. The extraction of free hydrophilic phenolic compounds was carried out in a hydroalcoholic solvent mixture via an ultrasound-assisted process. Furthermore, the solid residue was successively hydrolyzed by an alkaline solution to extract the bound phenolic fraction. Both free and bound extracted fractions were then quantitatively characterized for total polyphenolic and flavonoid contents, and the antioxidant potential was determined by carrying out the ABTS and DPPH radical scavenging assays, expressing the results (in both cases) as the Trolox equivalent antioxidant capacity (TEAC/ABTS and TEAC/DPPH, respectively). The samples were also extracted in organic apolar solvents (acetone or water-saturated iso-butanol) to quantitatively characterize lipophilic antioxidant compounds and pigments. A discussion on the comparison of these analytical parameters of flours obtained from raw, flaked, and precooked cereals and legumes is reported revealing that (i) phenolic compounds are mainly present in the post-hydrolysis extract (bound fraction), (ii) the precooking process significantly reduced the concentration of antioxidants, (iii) the flaking process slightly increased the phenolic content, (iv) legumes were less influenced by pretreatments, suggesting the possibility of using legumes to enrich cereal foods.

20.
Foods ; 11(16)2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-36010495

RESUMO

Coffea arabica L. leaves represent a viable alternative to the canonical matrices used for preparation of beverages, such as tea leaves and grounded coffee beans. Coffee leaves infusions are rich in antioxidant phenolic compounds and have a lower concentration of caffeine. Due to increasing interest in this field, a complete study of the bioactive compounds as chlorogenic acids, xanthones and alkaloids is noteworthy. C. arabica leaves were subjected to ultrasound-assisted extraction, and the extracts were studied via nuclear magnetic resonance spectroscopy (NMR) and chromatographic techniques coupled with mass spectrometry (HPLC-MSn) to identify and quantify the secondary metabolites profile through an untargeted data dependent approach. A quantitative analysis was performed for the major components-chlorogenic acids, mangiferin, caffeine and trigonelline-via HPLC-MS in Single Ion Monitoring (SIM) mode. In total, 39 compounds were identified. The presence of these bioactive compounds proved the strong potential of C. arabica leaves as functional food and as an alternative to classic infused beverages.

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