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1.
J Vis Exp ; (182)2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35467665

RESUMO

In this manuscript, three different step-by-step protocols to generate highly monodisperse emulsion drops using glass-based microfluidics are described. The first device is built for the generation of simple drops driven by gravity. The second device is designed to generate emulsion drops in a coflowing scheme. The third device is an extension of the coflowing device with the addition of a third liquid that acts as an electric ground, allowing the formation of electrified drops that subsequently discharge. In this setup, two of the three liquids have an appreciable electrical conductivity. The third liquid mediates between these two and is a dielectric. A voltage difference applied between the two conducting liquids creates an electric field that couples with hydrodynamic stresses of the coflowing liquids, affecting the jet and drop formation process. The addition of the electric field provides a path to generate smaller drops than in simple coflow devices and for generating particles and fibers with a wide range of sizes.

2.
Food Chem ; 372: 131263, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34818730

RESUMO

A combination of FTIR- and NMR-based metabolomics approaches coupled to multivariate data analysis techniques was used for the first time to characterize and explore the metabolic changes along the ripening of two Spanish melon landraces (Jimbee N and Jimbee XL). Furthermore, the fatty acids profile and the antioxidant capacity were investigated by GC-FID and ORAC method, respectively. Despite FTIR was able to identify changes in the sugars content between fruits of different maturity stages, it failed to discriminate between both varieties, being exceeded by NMR in both situations. Increased fruit maturation led to an increase of sucrose, fatty acids and ß-carotene, accompanied by a decrease of glucose, fructose, citrate, amino acids, and polyphenols (which were positively correlated with fruits antioxidant activity).


Assuntos
Cucumis melo , Cucurbitaceae , Frutas , Espectroscopia de Ressonância Magnética , Metabolômica
3.
Environ Res ; 184: 109341, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179266

RESUMO

Autism spectrum disorder (ASD) is a complex neurodevelopmental pathology characterized by altered verbalizations, reduced social interaction behavior, and stereotypies. Environmental factors have been associated with its development. Some researchers have focused on pesticide exposure. Chlorpyrifos (CPF) is the most used Organophosphate. Previous developmental studies with CPF showed decreased, enhanced or no effect on social outcomes eminently in mice. The study of CPF exposure during preweaning stages on social behavior is sparse in mice and non-existent in rats. d stressors could be at the basis of ASD development, and around postnatal day 10 in the rat is equivalent to the human birthday in neurodevelopmental terms. We explored the effects of exposure to low doses (1mg/kg/mL/day) of CPF during this stage regarding: sociability, dominance gut microbiome and plasma metabolomic profile, since alterations in these systems have also been linked to ASD. There was a modest influence of CPF on social behavior in adulthood, with null effects during adolescence. Dominance and hierarchical status were not affected by exposure. Dominance status explained the significant reduction in reaction to social novelty observed on the sociability test. CPF induced a significant gut microbiome dysbiosis and triggered a hyperlipidemic, hypoglycemic/hypogluconeogenesis and a general altered cell energy production in females. These behavioral results in rats extend and complement previous studies with mice and show novel influences on gut metagenomics and plasma lipid profile and metabolomics, but do not stablish a relation between the exposure to CPF and the ASD phenotype. The effects of dominance status on reaction to social novelty have an important methodological meaning for future research on sociability.


Assuntos
Transtorno do Espectro Autista , Clorpirifos , Microbioma Gastrointestinal , Inseticidas , Adulto , Animais , Transtorno do Espectro Autista/induzido quimicamente , Clorpirifos/toxicidade , Feminino , Humanos , Inseticidas/toxicidade , Camundongos , Ratos , Comportamento Social
4.
J Agric Food Chem ; 67(46): 12972-12985, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31709797

RESUMO

Controlling the temperature inside a greenhouse during the summer is a problem of increasing importance in the Mediterranean countries, especially in the Spanish southeast. The metabolic profile of greenhouse tomatoes and leaves grown under conventional conditions and within the presence of a shade mesh (∼50% reduction of sunlight radiation) has been monitored. Tomatoes were weekly harvested from May to July 2017 and analyzed by NMR spectroscopy coupled to multivariate data analysis techniques, together with oxygen radical absorbance capacity (ORAC) assays (for antioxidant activity). Fatty acids and carotenoids profiles were unraveled by GC-FID and HPLC-DAD, respectively. To verify whether it would be possible to take advantage of different light growing conditions to potentiate a plant's defense system, leaves of the corresponding plants were collected and their methanolic extracts were analyzed by NMR toward deciphering new biomarkers, which were used to assess their antibacterial and antibiofilm activities. The presence of a shading mesh resulted in a reduction in tomato production and in smaller fruits with lower contents of sugars (glucose and fructose) and carotenoids (lycopene and ß-carotene) and higher contents of organic acids, amino acids, and polyunsaturated fatty acids (linoleic and oleic acids) and of phenylpropanoids and flavonoids (which contributed to an increased antioxidant activity). Methanolic extracts of leaves of nonshaded plants showed a higher antibiofilm activity than that from shaded plants. This activity was well-correlated with an increase of phenolic compounds, together with some specific amino acids and organic acids from tomato leaves.


Assuntos
Frutas/química , Folhas de Planta/química , Solanum lycopersicum/efeitos da radiação , Antioxidantes/metabolismo , Alimentos Orgânicos/análise , Alimentos Orgânicos/efeitos da radiação , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Frutas/efeitos da radiação , Solanum lycopersicum/química , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Espectroscopia de Ressonância Magnética , Metaboloma/efeitos da radiação , Metabolômica , Valor Nutritivo/efeitos da radiação , Extratos Vegetais/química , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Luz Solar
5.
J Agric Food Chem ; 67(14): 3879-3889, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30920825

RESUMO

NMR spectroscopy coupled with multivariate data analysis techniques was applied to obtain meaningful information about nontargeted metabolic changes on  Isochrysis galbana upon acclimation to different environmental conditions at indoor lab-scale. The effects of temperature (from 15 to 30 °C) and incident irradiance (from 250 to 1600 µmol m-2 s-1) at a constant dilution rate of 0.3 h-1 were evaluated. High irradiances stimulated a decrease of chlorophyll a, fucoxanthin and amino acids content, and the conversion of polar fatty acids (PLs, GLs, DGDGs, SGDGs) to neutral fatty acids (saturated and unsaturated). High temperatures together with high irradiances decreased PUFAs concentration, including omega-3 fatty acids. Under low irradiance and temperature organic osmolytes (homarine, DMSP, GBT, and glycerol), and sugars (glucose, trehalose, and galactose) were also reduced.


Assuntos
Haptófitas/química , Haptófitas/efeitos da radiação , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Microalgas/química , Microalgas/efeitos da radiação , Aminoácidos/química , Aminoácidos/metabolismo , Clorofila A/química , Clorofila A/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados , Haptófitas/metabolismo , Microalgas/metabolismo , Temperatura
6.
Plant Foods Hum Nutr ; 74(1): 40-46, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30324543

RESUMO

Plants, including most food and feed plants, produce a broad range of bioactive chemical compounds. Among these compounds, polyphenols are reported to provide beneficial effects as anti-carcinogenic, anti-atherogenic, anti-inflammatory, immune modulating, anti-microbial, vasodilatory and analgesic. Cocoa (Theobroma cacao), a major, economically important, international crop, has been related to several nutritional benefits, which have been associated with the phenolic fraction. The main subclass of flavonoids found in cocoa is flavanols, particularly (epi)catechins monomers, and their oligomers, also known as procyanidins. In this study, these compounds were isolated by different methodologies as solid phase extraction (SPE), semi-preparative high-performance liquid chromatography (HPLC) and membrane technologies to obtain different polyphenolic profiles by HPLC coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and to test their cytotoxicity. Finally, different polyphenolic profiles were collected, where the combination of both semi-preparative HPLC and SPE technologies provided the most purified fractions. Filtration with membranes and SPE provide extracts with different composition depending on the pore size of membranes and on the solvent, respectively. In addition, the results of toxicity assay indicated low levels in all fractions.


Assuntos
Cacau/química , Flavonoides/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão , Flavonoides/toxicidade , Inocuidade dos Alimentos , Análise de Perigos e Pontos Críticos de Controle , Humanos , Compostos Fitoquímicos/toxicidade , Polifenóis/isolamento & purificação , Polifenóis/toxicidade , Proantocianidinas/isolamento & purificação , Proantocianidinas/toxicidade , Espectrometria de Massas por Ionização por Electrospray
7.
Analyst ; 143(19): 4707-4714, 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-30183032

RESUMO

Quantitative boron-11 NMR (11B qNMR) spectroscopy has been introduced for the first time as a method to determine boric acid content in commercial biocides. Validation of the method affords a limit of detection of 0.02% w/w and a limit of quantification of 0.04% w/w, which are low enough to determine boric acid in commercial biocides. Other figures of merit such as linearity (R2 > 0.99), recovery (93.6%-106.2%), intra- and inter-day precision (from 0.7 to 2.0%), uncertainty (3.7 to 4.4%) and matrix effects were also evaluated. This method was successfully applied to determine boric acid in five different commercial biocides in a wide range of concentrations (<0.05 to 10% w/w) providing excellent results when they were compared with those obtained using inductively coupled plasma-mass spectrometry (ICP-MS). The suitability of this method for a fast and reliable quantification of boric acid in commercial biocide preparations has been demonstrated. The absence of the matrix effect allows the application of this validated method for the determination of boric acid in other matrices of diverse composition.

8.
J Agric Food Chem ; 66(31): 8422-8432, 2018 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-30047728

RESUMO

This study describes the approach of 1H NMR metabolomic profiling for the differentiation of zucchini produced under different conditions of water irrigation (desalinated seawater -0.397 dS/m, 0.52 €/m3 vs groundwater -2.36 dS/m, 0.29 €/m3) and ventilation (surface area of the vent openings/greenhouse area was 15.0% for one sector and 9.8% for the other). Overall, 72 extracts of zucchini ( Cucubirta pepo L. cv Victoria) under four different conditions were regularly analyzed during the spring-summer cycle from April to July 2017. We have found that zucchini plants irrigated with desalinated seawater increased the zucchini production yield, presented fruits with higher concentration of glucose, fructose, and vitamin B3, and displayed an increased antioxidant activity. On the contrary, plant groundwater irrigation produced the increment of sucrose level that could rise the sweetness perception of the fruits. Finally, the ventilation variable produced a higher concentration of trigonelline, histidine, and phenylalanine but only on those zucchinis irrigated with groundwater.


Assuntos
Agricultura/métodos , Cucurbita/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Irrigação Agrícola/métodos , Agricultura/instrumentação , Antioxidantes/análise , Frutose/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Glucose/análise , Água Subterrânea , Niacinamida/análise , Extratos Vegetais/química , Água do Mar , Ventilação , Água
9.
Anal Bioanal Chem ; 410(15): 3607-3619, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29629503

RESUMO

Annona cherimola Mill. (cherimoya) has widely been used as food crop. The leaves of this tree possess several health benefits, which are, in general, attributed mainly to its bioactive composition. However, literature concerning a comprehensive characterization based on a combined approach, which consists of nuclear magnetic resonance (NMR) and high-performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-TOF-MS), from these leaves is scarce. Thus, the aim of this work was to study the polar profile of full extracts of cherimoya leaves by using these tools. Thus, a total of 77 compounds have been characterized, 12 of which were identified by both techniques. Briefly, 23 compounds were classified as amino acids, organic acids, carbohydrates, cholines, phenolic acid derivatives, and flavonoids by NMR, while 66 metabolites were divided into sugars, amino acids, phenolic acids and derivatives, flavonoids, phenylpropanoids, and other polar compounds by HPLC-TOF-MS. It is worth mentioning that different solvent mixtures were tested and the total phenolic content in the extracts quantified (TPC via HPLC-TOF-MS). The tendency observed was EtOH/water 80/20 (v/v) (17.0 ± 0.2 mg TPC/g leaf dry weight (d.w.)) ≥ acetone/water 70/30 (v/v) (16.1 ± 0.7 mg TPC/g leaf d.w.) > EtOH/water 70/30 (v/v) (14.0 ± 0.3 mg TPC/g leaf d.w.) > acetone/water 80/20 (v/v) (13.5 ± 0.4 mg TPC/g leaf d.w.). Importantly, flavonoids derivatives were between 63 and 76% of the TPC in those extracts. Major compounds were sucrose, glucose (α and ß), and proline, and chlorogenic acid and rutin for NMR and HPLC-TOF-MS, respectively. Graphical abstract The combined use of LC-HRMS and NMR is a potential synergic combination for a comprehensive metabolite composition of cherimoya leaves.


Assuntos
Annona/química , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/química , Folhas de Planta/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Flavonoides/análise , Fenóis/análise
10.
Food Chem ; 171: 341-50, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25308678

RESUMO

The effect of 2-chloroethylphosphonic acid (Ethephon, in the following ETH) as abscising agent on cv. Crimson Seedless table grape was investigated by means of Fruit Detachment Force (FDF) and Fruit Drop (FD) analyses combined with a metabolomic study carried out by High Resolution Mass Spectrometry (HRMS) and Nuclear Magnetic Resonance (NMR) spectroscopy. The effectiveness of ETH as abscising agent was ascertained with ETH concentration ranging from 1.4 to 4.0 g/L in a two-year study. The ETH treatments caused berry drops higher than 40% and induced an increase of tartaric acid, procyanidin P2, terpenoid derivatives and peonidin-3-glucoside as well as a decrease of catechin and epicatechin. HRMS-NMR covariance analysis was carried out to correlate the fluctuations of tartaric acid NMR signals to those of MS peaks of the secondary metabolites affected by ETH treatments.


Assuntos
Frutas/química , Compostos Organofosforados/farmacologia , Reguladores de Crescimento de Plantas , Vitis/química , Flavonoides/análise , Indústria Alimentícia/métodos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Metabolômica/métodos
11.
Dalton Trans ; 42(31): 11212-9, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23807438

RESUMO

The synthesis and characterization of three novel heterobimetallic derivatives of general formula [RuClCp(PPh3)-µ-dmoPTA-1κP:2κ²N,N'-MCl2] (M = Co (1), Ni (2) and Zn (3), dmoPTA = 3,7-dimethyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane) are described. The sizes of their diffusing units are in agreement with the solid-state structures of 2 and 3, supporting a similar solid-state structure for complex 1. The diamagnetic ruthenium-zinc derivative 3 was fully characterized in solution at 193 K by NMR. Electrochemical properties of the complexes were investigated by cyclic voltammetry, supporting the influence of the {MCl2} moiety on the electronic properties of the Ru-unit. For the three complexes the GI50 values were in the range 0.8-6.5 µM and comparable to those of the standard anticancer drug cis-platin in the same cell lines.


Assuntos
Antineoplásicos/síntese química , Cobalto/química , Complexos de Coordenação/síntese química , Níquel/química , Rutênio/química , Zinco/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/toxicidade , Cristalografia por Raios X , Técnicas Eletroquímicas , Células HeLa , Humanos , Conformação Molecular
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