This work brings the promise of MCM-41 mesoporous silica as a vehicle for red propolis for the development of controlled release drugs and delivery to a specific target site. The synthesis of MCM-41 by the sol–gel method with a pore size of approximately 3.6 nm and the incorporation of red propolis extract by the physical adsorption method in ethanolic medium were easily accomplished with around 15% encapsulation. MCM-41 and MCM-41 with red propolis (MCM-41/Pr) were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, thermal analysis, N₂ adsorption–desorption, scanning electron microscopy, and an ultra-high-performance liquid chromatography–diode array detection (UPLC-DAD). In vitro release of encapsulated red propolis was analyzed in phosphate buffer at pH 7.2, 7.4, and 7.6. An in vitro test for MCM-41/Pr antioxidant activity was performed using 2,2-diphenyl-1-picrylhydrazyl as well as analysis of antibacterial activity against Staphylococcus aureus by the well diffusion method. UPLC-DAD analysis showed that the integrity of the red propolis constituents was maintained after the embed process, and the antioxidant and antibacterial activities were preserved.

The objective of this work was to evaluate and compare the potential of polyurethane and kapok (Chorisia speciosa) residues as sorbent materials in the treatment of diesel spillage. To determine the sorption capacity, gravimetric tests were performed in static medium at room temperature and at different temperatures (10, 15 and 28 °C) and varying the time of contact between the sorbent material and diesel. It was observed that the sorption process occurs at a high velocity, with saturation point achieved in the first 5 minutes of contact, and the natural fiber presents higher sorption capacity compared to the polyurethane residue due to the low viscosity of diesel oil, that contributes to reduce de entrapment inside the porous foam. It has also been observed that the polyurethane residue exhibits an increase in sorption capacity with time and temperature increase. Scanning electron microscopy (SEM) analysis have shown that the main morphological property involved in smooth oil sorption was the high porosity associated with a small porous diameter. The kapok presented sorption capacity of 37 g/g in equilibrium demonstrating its great potential of application as a sorbent material for the treatment of diesel spillage.

The search for efficient oil spill remediation techniques leads to the use of physical, chemical, and biological methods, featuring both natural and modified lipophilic materials. Kapok fibers (Ceiba pentandra (L.) Gaerth) have been studied as a result of their unusual natural oil sorption capacity, which can be improved even further through physical or chemical treatments that augment their rugosity and alter their functional properties. Furthermore, the exact role of fiber morphology is not completely clear regarding the sorption process. Hence, this study investigated the efficacy of kapok fibers using different treatments, based on chemical and physical approaches, and characterized using advanced techniques (FTIR, SEM, AFM), aiming to improve the understanding of application possibilities in oil contamination scenarios. The results indicate that treatments using a low thermal intensity and low concentration do not lead to variation in sorption properties nor in surface structural features. Fiber rugosity varied from 4.40 to 12.35 nm, whereas an excessive increase in roughness was observed when the material was subject to more extreme conditions, such as a temperature of 120 °C and high concentrations (2.0 M) of both acid or alkali, accompanied by a loss in functionality and affecting the material sorption capacity. Thus, the study provides conditions to suggest that these treatments are not necessary for this type of material when inserted into sorption processes.