Cristina Maria Zanette

As redes sociais são ferramentas poderosas de comunicação mas que, frequentemente, têm seu potencial subutilizado, chegando a serem classificadas como distrações, especialmente no meio acadêmico. Neste contexto, este trabalho compartilha o processo de difusão de informações relacionadas ao curso de Engenharia de Alimentos da Unicentro e à atuação nesta profissão decorrentes do projeto de extensão “Alimentando conhecimento na comunidade: A importância do Engenheiro de Alimentos”. Para isto, as redes sociais (Instagram, Facebook, TikTok e Youtube) foram reestruturadas e utilizadas para expor atividades realizadas por alunos, docentes e profissionais. Além disso, foram desenvolvidas ações de cunho teórico e prático em parceria com instituições de ensino fundamental e médio como forma de divulgar a profissão. O uso de redes sociais permitiu a aproximação entre universidade e sociedade alavancando o número se seguidores nas plataformas, indicando ser uma estratégia interessante para a propagação das ações desenvolvidas pelo curso e pelos profissionais.

Co-abietate and Cu-abietate complexes were obtained by a low-cost and eco-friendly route. The synthesis process used Pinus elliottii resin and an aqueous solution of CuSO₄/CoSO₄ at a mild temperature (80 °C) without organic solvents. The obtained complexes are functional pigments for commercial architectural paints with antipathogenic activity. The pigments were characterized by Fourier-transform infrared spectroscopy (FTIR), mass spectrometry (MS), thermogravimetry (TG), near-edge X-ray absorption fine structure (NEXAFS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and colorimetric analysis. In addition, the antibacterial efficiency was evaluated using the minimum inhibitory concentration (MIC) test, and the antiviral tests followed an adaptation of the ISO 21702:2019 guideline. Finally, virus inactivation was measured using the RT-PCR protocol using 10% (w/w) of abietate complex in commercial white paint. The Co-abietate and Cu-abietate showed inactivation of >4 log against SARS-CoV-2 and a MIC value of 4.50 µg·mL⁻¹ against both bacteria Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The results suggest that the obtained Co-abietate and Cu-abietate complexes could be applied as pigments in architectural paints for healthcare centers, homes, and public places.

The synthesis of structured MgO is reported using feedstock starch (route I), citrus pectin (route II), and Aloe vera (route III) leaf, which are suitable for use as green fuels due to their abundance, low cost, and non-toxicity. The oxides formed showed high porosity and were evaluated as antimicrobial agents. The samples were characterized by energy-dispersive X-ray fluorescence (EDXRF), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The crystalline periclase monophase of the MgO was identified for all samples. The SEM analyses show that the sample morphology depends on the organic fuel used during the synthesis. The antibacterial activity of the MgO-St (starch), MgO-CP (citrus pectin), and MgO-Av (Aloe vera) oxides was evaluated against pathogens Staphylococcus aureus (ATCC 6538P) and Escherichia coli (ATCC 8739). Antifungal activity was also studied against Candida albicans (ATCC 64548). The studies were carried out using the qualitative agar disk diffusion method and quantitative minimum inhibitory concentration (MIC) tests. The MIC of each sample showed the same inhibitory concentration of 400 µg. mL⁻¹ for the studied microorganisms. The formation of inhibition zones and the MIC values in the antimicrobial analysis indicate the effective antimicrobial activity of the samples against the test microorganisms.

We report on the synthesis of boehmite aluminum oxide hydroxide particles with lamellar structure (γ-AlO(OH)) obtained from the recycling of metallic can seals, with the addition of silver nanoparticles (Ag-NPs) reduced by Aloe Vera extract. X-ray diffractometry (XRD) confirmed the γ-phase, and scanning electron microscopy (SEM) showed the presence of Ag-NPs on the boehmite particle surface, confirming the efficiency of the synthesis to obtain the composite material. The samples were used to treat lake water, according to the Standard Methods for the Examination of Water and Wastewater. The results indicated that the elimination of total coliforms and Escherichia coli occurred, with excellent efficiency for the Ag-boehmite sample. The tests show the possibility of reuse (5×) of the sample, as it maintained the efficiency of disinfection for E. coli. The preparation, use, and reuse of boehmite obtained from metallic waste is a case of a circular economy, focused on sustainability and green chemistry.

In this study, two green synthesis routes were used for the synthesis of Ag/ZnO nanoparticles, using cassava starch as a simple and low-cost effective fuel and Aloe vera as a reducing and stabilizing agent. The Ag/ZnO nanoparticles were characterized and used for bacterial disinfection of lake water contaminated with Escherichia coli (E. coli). Characterization indicated the formation of a face-centered cubic structure of metallic silver nanoparticles with no insertion of Ag into the ZnO hexagonal wurtzite structure. Physicochemical and bacteriological analyses described in “Standard Methods for the Examination of Water and Wastewater” were used to evaluate the efficiency of the treatment. In comparison to pure ZnO, the synthesized Ag/ZnO nanoparticles showed high efficiencies against Escherichia coli (E. coli) and general coliforms present in the lake water. These pathogens were absent after treatment using Ag/ZnO nanoparticles. The results indicate that Ag/ZnO nanoparticles synthesized via green chemistry are a promising candidate for the treatment of wastewaters contaminated by bacteria, due to their facile preparation, low-cost synthesis, and disinfection efficiency.

Bacteria, yeast, and microalgae are sources of biomolecules such as enzymes, lipids, pigments, organic acids and, proteins for industrial application. These high-added-value biomolecules are often intracellularly bioaccumulated, and their recovery involves several downstream processes, in which the most crucial stage is the disruption of the cell wall. The choice of the method influences the further downstream steps and, consequently, its complexity and cost. In this review, severe and gentle methods currently used for disruption or permeabilization of bacteria, yeast, and microalgae were discussed based on their principle, application, and feasibility. Also, recent studies regarding the microbial cell disruption were presented in order to facilitate the choice of the more effective method. Some factors such as cell wall composition, nature of biomolecule, purity degree, scalability, and energy input are necessary to be considered on selecting the most appropriate disruption method. The severe methods, such as high pressure-homogenization, and ultrasonication present higher yield, lower cost, and feasibility to scale-up when compared to the gentle methods. However, in order to achieve a higher recovery yield, further studies must focus on the optimization of operational parameters and on the combination of severe and gentle methods.