Resumo em Inglês:

Metabolomics can provide a readout of the biochemical and physiological state of a biological system. Gas chromatography coupled to mass spectrometry (GC-MS) has been widely applied for metabolomic analysis due to its numerous advantages, such as good sensitivity, high resolution, reproducibility, extensive database, lower acquisition cost and greater coverage. In addition, combined with efficient methods of sampling and sample preparation, the metabolomic analysis of damaged skin based on GC-MS can provide an important step toward elucidating several skin diseases. Based on this, this review presents a comprehensive overview of sampling, sample preparation, data processing and GC-MS analysis of metabolomic studies of damaged skin. Also, part of the biological interpretation of metabolites such as cis- and trans-urocanic acid (UCA) altered in photoexposed skin and lauric acid (C12:0) and palmitic acid (C16:0) in melanoma is discussed. Finally, to improve decision-making, a part of the integration of skin metabolomics with other omics sciences for the advancement of diagnosis is presented.

Resumo em Inglês:

Arthropod-borne viruses (arboviruses) are a severe public health problem worldwide, consisting of a significant part of all the emerging infectious diseases. It is estimated that arboviruses infect hundreds of millions of people globally each year, resulting in several thousand deaths. Despite their clear health threat, there are no prophylactic or pharmacological therapies available for most of them. Control of arbovirus infections is beyond pharmacological options; handling the larvae of mosquitos is an important and successful strategy, although currently available insecticides and larvicides are already associated with resistance. Therefore, searching for new strategies to prevent arbovirus infection is urgent and necessary. Marine organisms are an excellent source for structurally novel compounds due to their unique secondary metabolism, with outstanding antiviral and larvicidal activities. In the present review, we explored the ability of various marine natural products (MNPs) such as indole derivatives, diketopiperazines, scequinadoline A, cyclohexadepsipeptides, and others, to act as both antiviral and larvicidal, in an attempt to highlight their structure activity potential against the most relevant arboviruses affecting the human health.

Resumo em Inglês:

Chiral aminomethylnaphthols have been prepared highly diastereoselective by means of three-component “Betti condensation”, using steroidal 2-naphthol analogue, synthesized from estrone. The use of 2-methoxybenzaldehyde or 2-pyridinecarboxaldehyde as aldehyde component and (S)-(–)-1-phenylethan-1-amine or (S)-(–)-1-(naphthalen-2-yl)ethan-1-amine, as chiral non-racemic amine component providing the diastereoselectivity, allowed the synthesis of structurally diverse aminomethylnaphthols. The latter easily form 1,3-dihydronaphthoxazines through reaction with formaldehyde. The absolute configurations of the new aminomethylnaphthols synthesized have been determined through advanced nuclear magnetic resonance (NMR) experiments and confirmed by X-ray crystallography. The chiral steroidal aminomethylnaphthols obtained as pure diastereoisomers have been evaluated as pre-catalysts in the enantioselective addition of diethylzinc to aldehydes with enantioselectivities of up to 97% enantiomeric excess (ee).

Resumo em Inglês:

This study determined the levels of total mercury in Spanish samples of baby food, fast food, and daily meal, which people of different ages consume, to evaluate potential toxicological risks through the contribution to the tolerable daily intake (TDI). The total mercury concentrations were determined in thirteen commercial baby foods for infants 6 to 12 months old, six types of fast foods prepared for children, and nine canteen menus prepared for adults. Samples were analyzed using a direct mercury analyzer, and the following concentration ranges were found: baby food (0.57-41.9 µg kg-1), fast food (0.54-68 µg kg-1), and adult menus (0.43-638 µg kg-1). The recovery of different amounts of spiked mercury ranged from 98.6 to 104.9%, and the method’s accuracy was checked with an analysis of different certified reference materials. The limits of detection and quantification obtained were 0.1 and 0.3 µg kg-1, respectively, with a relative standard deviation of up to 11%. The contribution of the samples to the TDI varied as follows: baby food (0.3-28%), fast food (0.5-102%), and adult menus (0.3-396%). Therefore, it was concluded that total mercury daily intake does not pose risks for Spanish children and adults if tuna is not included on their menu.

Resumo em Inglês:

This work describes a green synthesis, the characterization, and biological evaluation of silver nanoparticles (AgNPs). The AgNPs suspension was synthesized using aqueous leaf extract of Eucalyptus grandis, which presented a characteristic band at 407 nm in the UV-Vis spectrum. The AgNPs presented a spherical shape and size of 9.7 ± 0.3 nm. The nanoparticles were stable over a month, indicating that E. grandis’ extract is suitable for their preparation and stabilization. The X-ray analysis showed that the crystallinity of AgNPs corresponded to the centered face phase of silver. The antibacterial and leishmanicidal activities of AgNPs were evaluated. The AgNPs presented antibacterial activity on the Gram-negative bacteria Escherichia coli at 53.9 µg mL-1. The leishmanicidal activity evaluation against promastigote forms of Leishmania infantum, Leishmania amazonensis, and Leishmania braziliensis showed that the biological response is dependent on the volume of AgNP suspension. It was demonstrated that L. infantum was more sensitive to the nanoparticle’s treatment than L. amazonensis and L. braziliensis. The treatment of L infantum promastigotes with 150 µL of AgNP suspension reduced parasite growth by 67.9%, a result which was similar to the treatment with 1 (66.7%) or 2 µL (70.6%) of amphotericin B used as a positive control.

Resumo em Inglês:

Naltrexone (NTX) and bupropion (BUP) are used in combination in clinical practice for obesity; however, the existing analytical methods for this drug combination are not sustainable. This work aims to develop an analytical method that is faster, easier and less expensive compared with high performance liquid chromatography (HPLC) and involves green technology without solvents to quantify BUP and NTX in combination. The objective was to validate a method using mid-infrared (MIR) spectroscopy associated with multivariate calibration and chemometrics to simultaneously measure NTX and BUP in a pharmaceutical capsule form. The models were developed using MIR spectroscopy with diffuse reflectance, with interval partial least squares (iPLS) variable selection. The working range selected to optimize the model was from 1885.8 to 1585.4 cm-1. The chosen model was obtained with partial least squares (PLS2) and with data pre-processed by first derivative Savitzky-Golay smoothing followed by mean centering, using four latent variables, providing a root mean square error of prediction of 1.8 mg g-1 for NTX and 6.42 mg g-1 for BUP. The method was validated according to current international standards. In conclusion, the methods developed in the MIR region provided statistically similar results to the validated chromatographic method for commercial pharmaceutical formulations.

Resumo em Inglês:

Pt-Y/C catalysts were prepared by a modified formic acid method and their structural characteristics and activity for oxygen reduction reaction (ORR) were evaluated. X-ray diffraction analysis showed that no alloy was formed between the metals and X-ray photoelectron spectroscopy (XPS) experiments showed that yttrium is presented as Y2O3, Y(OH)3 and Y-O-Pt species. CO stripping voltammetry and in situ X-ray absorption spectroscopy confirmed the interaction between Pt nanoparticles and yttrium species. The Pt-Y/C 7:3 material showed the higher specific activity (103 µA cmPt2) for ORR. Following repetitive potential cycling, the activity for the ORR of the Pt-Y/C 7:3 catalyst declined in a similar proportion to the Pt/C material. Transmission electron microscopy analysis after stability for both catalysts showed that Pt/C particle size slightly increased and that for Pt-Y/C 7:3 remained the same. XPS made in ultrathin catalyst layer, agreeing with energy-dispersive X-ray spectroscopy analysis, revealed that the intensities of the Y 3d peaks were suppressed relative to the initial one and that yttrium in the form of Y2O3 and Y(OH)3 were dissolved, while the species Y–O–Pt still remain in the catalyst, maintaining the higher activity.

Resumo em Inglês:

Anacardic acid (AA) is a bioactive phytochemical found in the nutshell of Anacardium occidentale, a tropical plant originally from Brazil. In this work, cross-linked anacardic acid nanocapsules (NC) were obtained by interfacial polymerization carried out using the inverse miniemulsion technique with 2,4-toluene diisocyanate (TDI). For this purpose, a functionalized monomer from AA was synthesized for formation of lipase-cleavable ester linkages by coupling of amino acids. The synthesis was planned so that when these ester linkages get exposed to an enzyme, they are broken down and released AA. Furthermore, the N-termini of the coupled amino compounds were used as sites for the polyaddition with TDI at the droplet interface in the inverse miniemulsion. The permeability of the shell was studied on the fluorescent dye, sulforhodamine 101 (SR101), using fuorescence spectroscopy After redispersion in water, the enzymatic cleavage of NC and the release of the SR101 were both monitored in real time. The released AA was proven to be active in vitro against Bacillus subtilis colonies in the bacterial tests. The results indicate that the use of NC is a promising strategy, which can make feasible the application of AA for therapeutic purposes and as nanocarriers for the delivery of active components.

Resumo em Inglês:

RN104 (2-[2-(cyclohexylmethylene)hydrazinyl]-4-phenylthiazole) is a thiazolylhydrazone derivative with promising in vitro and in vivo antifungal activity. A stability indicating highperformance liquid chromatography with diode-array detection (HPLC-DAD) method was carried out using C18 end-capped column (250 × 4.6 mm, 5 μm) and a mobile phase composed of water and acetonitrile (15:85 v/v) at a flow rate of 1.2 mL min-1, injection volume 25 μL and DAD detection at 240 nm. The method showed to be selective, linear in the range of 20 to 240 μg mL-1, precise, accurate and robust. RN104 forced degradation study under different stress conditions (acidic, alkaline and neutral hydrolysis, oxidation, photolysis and thermolysis) was performed using the validated analytical method. The results showed that RN104 underwent significant degradation when subjected to alkaline hydrolysis and oxidation by metallic ions. Quantum mechanics calculations were carried out to assist in the structural elucidation of the formed degradation products. The obtained data may be useful for the development of future formulation based on RN104.

Resumo em Inglês:

Fluopyram is a fungicide which can also be used as a nematicide in agricultural areas. The Brazilian Ministry of Agriculture authorized the commercialization and use of this molecule in Brazilian agriculture in 2019, but studies involving the development of an extraction and quantification method of this compound in environmental matrices such as soil are still scarce. Therefore, the present study aimed to optimize and validate the miniaturized version of the solid-liquid extraction with low temperature purification (SLE-LTP) method for determining this compound in sandy, clayey and medium-textured soil samples. All analyzes in this study were performed by gas chromatography coupled to mass spectrometry (GC-MS). The results revealed that the analyte recovery percentages in the three soil types ranged from 86 to 114% with a relative standard deviation of less than 15%. In addition to employing smaller amounts of reagents and sample, the miniaturized SLE-LTP method was selective, precise, exact, and linear in the range from 3 to 210 μg kg-1, and reached a limit of quantification lower than 3.00 μg kg-1 for the three soil types. The extraction method was applied to 30 real samples collected in coffee growing regions, but no residue of this compound was detected in these samples.

Resumo em Inglês:

In this work, a visible-light-driven synthesis of alkynyl selenides using [BMIm]BF4 as an environmentally friendly solvent and without the addition of metal catalysts, photosensitizers, directing-groups, or bases is reported. The target compounds were obtained in moderate to good yields with good functional group tolerance by the reaction of diorganoyldiselenides with 1-bromoalkynes proceeding through a radical mechanism.

Resumo em Inglês:

Vegetable oils are alternatives to producing renewable monomers since they are biomass. It is possible to react them with anhydrides by heating to provide monomers with high reactivity. However, after the reaction of grape seed oil with itaconic anhydride, it was observed the occurrence of parallel reactions that had not been observed when the same oil was reacted with maleic anhydride. Some articles in the literature have reported that temperature and bases can isomerize itaconic anhydride into citraconic anhydride, which is more stable at room temperature. However, they have not focused on completely understanding how this phenomenon occurred nor studied it in processes that involve microwave irradiation. Therefore, this paper presents a complete characterization and investigation about the thermal behavior of itaconic anhydride and how it can affect the monomer synthesis performed under heating.