Resumo em Inglês:

This study describes the chemical composition and biological activities of extracts and compounds obtained from the roots of Bowdichia virgilioides (Fabaceae). A mixture of very long-chain free fatty acids (VLFAs) and pure compounds, namely isocordoin, cordoin, lupeol, lupenone, β-sitosterol, stigmasterol, and sitostenone, were isolated from the soluble fraction of the methanol extract by using sequential column chromatography procedures. The molecular structures of the compounds were determined using infrared (IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS) techniques. Notably, this is the first report of the occurrence of both chalcones within this plant genus. Besides, the VLFAs were identified by electrospray ionization mass spectrometry (ESIMS) and the presence of these compounds in roots is suggested to be an adaptive response to environmental stress, which exhibited moderate antioxidant properties when tested against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and in the β-carotene/linolenic acid auto-oxidation assay. However, the MeOH soluble fraction demonstrated significant toxicity in the brine shrimp lethality assay.

Resumo em Inglês:

Microparticulated whey protein can be used as a fat substitute in foods to enhance their nutritional value and improve their sensory and rheological characteristics. Microparticulation denatures whey proteins through heat treatment, followed by shear rate control to determine the aggregate sizes formed. The processing method used during microparticulation can modify the protein denaturation rate, which may enable the application of new proteins. This study sought to develop a methodology for quantifying whey protein fractions in commercial samples before and after microparticulation at different concentrations and physical states. The developed methodology proved to be applicable because of its selectivity, quantification, detection limits, and precision. The analyzed samples exhibited a higher denaturation rate for β-lactoglobulin than α-lactoalbumin; the denaturation rate varied among samples due to differences in the microparticulation process.

Resumo em Português:

In last decades, technical-scientific investigations into cultural heritage assets have increasingly become part of analysis methodologies accessible to professionals from different areas for a broad understanding of the complex material and historical nature of objects. In this interdisciplinary word, the painting “Costureiras” by Tarsila do Amaral (1886-1973), from 1950, was studied by ultraviolet-induced visible luminescence (UVL), infrared image (IR) and macro X-ray fluorescence scanning (MA-XRF) techniques. UVL and MA-XRF images enabled the exploration of the conservation status of the artwork, the creative process of the artist, and areas featuring materials distinct from the original painting. By combining the results of IR and MA-XRF images, it was confirmed that changes occurred in the creative process during the composition of the artwork. MA-XRF images further allowed the inference of the primary pigments employed by the artist, revealing that, during canvas priming, Tarsila do Amaral utilized pigments based on lead and zinc.

Resumo em Inglês:

The real-time sensing of benzene, toluene, ethylbenzene, and xylene (BTEX) vapor has become urgent due to their widespread hazards. As a sensing platform that combines low energy consumption and high sensitivity, moisture-resistant detection of ppb-level BTEX vapor remains a challenge for quartz crystal microbalance (QCM) based gas sensors. In this work, we employed polyaniline nanofibers as the sensing material, significantly enhancing the QCM sensor’s detection capability for BTEX vapor down to the 50 ppb level. Besides, thanks to the hydrophobicity of polyaniline nanofibers, this sensor shows minimal response fluctuations to BTEX vapor in the relative humidity range of 50-90%. Furthermore, this sensor exhibits a short response time and excellent long-term stability, thereby presenting a broad prospect for future industrial applications in BTEX vapor detection.

Resumo em Português:

The study of adsorption kinetics has been gaining ground, due to the fact that adsorption is an operation used in several areas, which drives the development of software for calculating kinetic parameters. In this context, the work aims to develop and validate a free software, with an intuitive interface and easy operation, for processing adsorption kinetic analysis data. The Adsorption Kinetics Calculation (AKC) software was developed in Java language, using Apache Netbeans IDE (integrated development environment) and has three kinetic equations implemented in a non-linear way: pseudo-first order, pseudo-second order and intraparticle diffusion implemented and also generates the parameters statistical coefficient of determination (R2) and ARE (average relative error). The software was successful in programming the algorithms, because the parameter values (Qe and C) were similar to the experimental values and the error values (R2 and ARE) were within those predicted by the literature. The software has the ability to plot the results and all results showed reliability in the data generated, and it can be concluded that it is validated and ready to be made available for users to use in their research.