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Polymeric nanofibers are materials that can be used as scaffolds in tissue engineering. Quercetin and curcumin are antioxidants because of scavenge free radicals and chelate metal ions properties, protecting tissues of lipid peroxidation. The objective of this study was to develop a scaffold with potential antioxidant activity that was produced from nanofibers consisting of polycaprolactone (PCL) and a blend of PCL/poly(hydroxybutyrate-co-hydroxyvalerate) (PHB-HV) with the addition of quercetin or curcumin as the bioactive compound. Curcumin and quercetin were integrated into the solution at a concentration of 3%. The electrospun nanofibers were characterized using calorimetry and thermogravimetric analysis, and the addition of bioactive compounds did not alter the thermal properties of the biomaterial. The antioxidant activity of scaffolds with the active compounds was evaluated by hydrate 2,2-diphenyl-2-picrylhydrazyl (DPPH) and 2,2 0 -azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) methods. The scaffolds with PCL and PCL/PHB-HV blend with quercetin exhibited higher antioxidant activity than curcumin with both methods.

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Polymer nanofibers are nanomaterials that can be used as scaffolds in tissue engineering. The objective of this study was to develop, characterize and evaluate the in vitro degradation of a biomaterial consisting of nanofibers produced from biodegradable and biocompatible polymers with potential applications as a scaffold for tissue regeneration and containing Spirulina sp. LEB 18 biomass as the bioactive compound. The polymers used were poly(hydroxybutyrate-co-hydroxyvalerate) and polycaprolactone. The polymeric solutions exhibited sufficiently high viscosity to produce uniform nanofibers with diameters between 335 and 617 nm. The applied conditions were as follows: a voltage of 25 kV, a distance from the capillary to the collector of 120 mm, a capillary diameter of 0.80 mm, and 12% polycaprolactone and a blend of 5% polycaprolactone and 10% poly(hydroxybutyrate-co-hydroxyvalerate). The biomass was incorporated into the nanofibers at a concentration of 3%, and the incorporation was confirmed using confocal microscopy. The nanofibers were characterized using differential scanning calorimetry and thermogravimetric analysis, which showed that the addition of biomass did not alter the thermal properties of the biomaterial. The addition of biomass improved the tensile strength and elongation of the scaffolds compared with those produced with polymers alone. A biodegradation assay showed enzymatic action toward the biomaterial, simulating the behavior of natural tissue. Based on the analysis, it was concluded that the scaffolds that were produced have the potential to be applied in the field of tissue regeneration as biomaterials with pharmacological properties.

Biorefineries based on microalgae produce biofuels and co-products with added value. Microalgae mainly require water, carbon dioxide and sunlight for growth. The bioproducts of the cultivation of these microorganisms can be fully used in a microalgae photobiorefinery. The objective of this work was to study the behavior of physico-chemical variables and kinetic and biological responses in industrial cultivation of Spirulina sp. LEB 18, aiming at the operation of a microalgal photobiorefinery. The maximum specific growth rate (0.133 1/d), the minimum generation time (5.2 d) and maximum productivity (14.9 g/m².d) were obtained in the first 9 d of microalgae growth. The maximum biomass concentration (1.64 g/L) was obtained in 37 d of cultivation. The highest levels of carbohydrates, proteins and lipids in the biomass were 10.6, 57.0 and 11.7%, respectively. The plant monitoring demonstrated that the microalgae produced biomass with high quality for application as biofuels, energy, health and nutrition human.