Bacterial cellulose (BC) has been produced for a number of applications, mainly focused on the biomedical area. Although there is a variety of interesting applications of BC for food and food packaging, only a few have been explored to the moment, since the high cost of BC production is usually considered as a limiting factor. On the other hand, several cost-effective culture media have been proposed, contributing to reduce BC production costs. This article overviews the bioprocess conditions that affects BC production and the main possible applications of BC for food and food packaging purposes.

In this article, a new approach is applied to reuse Artemisia residue (AR) as filler in polyurethane (PU) foam for vegetable oil sorption for discarded cooking oil applications. The pristine PU and PU/X%AR foams (X stands for AR content of 5–20%wt/wt) were characterized by SEM, density, contact angle (CA), thermogravimetric analysis, and Fourier transform infrared spectroscopy. The influence of two experimental factors, such as contact time (30–180 s) and initial vegetable oil concentration (20–200 g/L), was investigated in vegetable oil and vegetable oil/mineral water systems. The AR loading of the foams increased the foams' density and influenced the morphological, physical, thermal, and sorption properties. The PU/20%AR sample presented the highest CA (122.5°) and the best sorption capacity and efficiency in both systems due to the small pores size and higher frequency of pores. Langmuir and Freundlich isotherm models well defined the sorption mechanisms. The Langmuir model represented the best fit of experimental data for PU/20%AR with a maximum adsorption capacity of 16.86 g/g. The PU/20%AR presented reusability of 7 cycles, conserving their hydrophobicity after the process. Therefore, AR is an innovative route as fillers in PU foams for discarded vegetable oil sorption, and the circular economy can benefit from the reuse of discarded vegetable cooking oil.

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This study presents an alternative to reducing solid waste, improving the concept of green composites. So, the use of fibers from pine cone as reinforcement in acrylonitrile butadiene styrene (ABS) composites filaments as a potential for 3D pen was evaluated. The effect of the treatment chemical (alkaline and bleaching) was studied. A thermokinetic mixer processed the ABS/pine cone fibers (2 and 5% wt.) composites. After, the filaments were prepared by mini extruder and printing 3D pen. Filaments were characterized by Scanning Electron Microscopy (SEM), Thermogravimetry (TGA), and Infrared Spectroscopy (FTIR). Filaments revealed homogeneous diameters. The addition of 2 and 5% wt. fiber not significantly influenced the filament’s diameter and density. On the other hand, thermal stability and morphological analysis influenced the type of fiber (raw, treated, and bleached). The addition of bleached fibers to ABS increased composites’ thermal stability compared to other fibers (treated and raw). Also, inserting bleached fibers was perceptible a uniformly distributed and embedded throughout the wire cross-section compared to treated and raw fiber added to ABS due to good interfacial bonding. Results indicated that fibers were hydrogen-bonded to ABS chains and increased the filament’s density. So, it is possible to affirm that the addition of fibers from pine cone to ABS thermally improved and can be a low-cost feedstock for printing 3D pen applications. Despite the low concentration of natural fiber on the composites investigated in this work, the successful obtainment of ABS reinforced with biodegradable natural fiber, compromising neither its thermal properties nor its processability and printability, opens the possibility for future work investigation into a composite with larger fiber content.

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