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The high consumption of packaging has led to a massive production of waste, especially in the form of nonbiodegradable polymers that are difficult to recycle. Microbial cellulose is considered a biodegradable, low-cost, useful, ecologically correct polymer that may be joined with other biomaterials to obtain novel characteristics and can, therefore, be used as a raw material to produce packaging. Bagasse, a waste rich in plant cellulose, can be reprocessed and used to produce and reinforce other materials. Based on these concepts, the aim of the current research was to design sustainable packaging material composed of bacterial cellulose (BC) and sugarcane bagasse (SCB), employing an innovative shredding and reconstitution method able to avoid biomass waste. This method enabled creating a uniform structure with a 0.10-cm constant thickness, classified as having high grammage. The developed materials, particularly the 0.7 BC/0.3 SCB [70% (w/w) BC plus 30% (w/w) SCB] composite, had considerable tensile strength (up to 46.22 MPa), which was nearly thrice that of SCB alone (17.43 MPa). Additionally, the sorption index of the 0.7 BC/0.3 SCB composite (235.85 ± 31.29 s) was approximately 300-times higher than that of SCB (0.78 ± 0.09 s). The packaging material was also submitted to other analytical tests to determine its physical and chemical characteristics, which indicated that it has excellent flexibility and can be folded 100 times without tearing. Its surface was explored via scanning electron microscopy, which revealed the presence of fibers measuring 83.18 nm in diameter (BC). Greater adherence after the reconstitution process and even a uniform distribution of SCB fibers in the BC matrix were observed, resulting in greater tear resistance than SCB in its pure form. The results demonstrated that the composite formed by BC and SCB is promising as a raw material for sustainable packaging, due to its resistance and uniformity. [ABSTRACT FROM AUTHOR]

One of the main challenges in the treatment of industrial wastewater is the removal of oil-in-water emulsions, which are stable and therefore difficult to treat. Bacterial cellulose (BC) has structural characteristics that make it an ideal filtration membrane. Several research projects are underway to develop new materials, both biotechnological and traditional, for use in filter beds. The study examined the potential of a BC membrane filtration system for treating oily industrial wastewaters, an underexplored biomaterial in wastewater treatment. The results demonstrated that BC is highly effective at removing oily contaminants (~99%), reducing the colour and particulate matter of wastewater, as well as eliminating nearly the entire microbiological load (~99%). SEM, MEV, FTIR, XRD, and TGA confirmed the presence of oil in the interior of the membrane after filtration, characteristic peaks of its chemical composition, and a 40% reduction in crystallinity. TGA revealed an increase from three (pre-filtration) to five (post-filtration) stages of thermal degradation, indicating the retention of the contaminant in the BC. The mechanical tests demonstrated that the membrane has a tensile strength of 72.13 ± 8.22 MPa and tolerated elongation of up to 21.11 ± 4.81% prior to tearing. The BC membrane also exhibited excellent flexibility, as it could be folded >100 times at the same point without exhibiting signs of tearing. The BC surpasses traditional methods, such as activated charcoal and effluent treatment stations, in the removal of emulsified oils. The findings demonstrate that BC is promising for the treatment of industrial wastewaters, which is a field that requires continual technological innovations to mitigate the environmental impacts of the oil industry. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) can be chemically modified and combined with other materials to create composites with enhanced properties. In the medical field, biomaterials offer advantages, such as biocompatibility and sustainability, enabling improved therapeutic strategies and patient outcomes. Incorporating lidocaine into wound dressings offers significant potential benefits. In this study, transparent BC films were produced in situ with an undefined minimal culture medium with a yeast and bacteria co-culture system on black tea (Camellia sinensis) and white sugar medium for three days. Lidocaine was incorporated ex situ into the BC matrix, and the composite film was sterilized using gamma radiation. Drug-release studies showed a two-stage release profile, with an initial fast release (24.6%) followed by a slower secondary release (27.2% cumulative release). The results confirmed the incorporation of lidocaine into the BC, producing highly transparent films with excellent thermal stability, essential for the storage and transportation of wound dressings. This study highlighted BC properties and drug incorporation and release behavior. The findings contribute towards optimizing wound dressings with controlled drug release, showcasing the potential of transparent BC films as an effective platform for wound care and drug-delivery applications. [ABSTRACT FROM AUTHOR]

The environmental impacts of the exploration and use of petroleum and derivatives in recent decades have led to increasing interest in novel materials and processes for the treatment of oily effluents. Oily emulsions are difficult to manage and, in some cases, require different types of treatment or combined methods for phase separation. Sustainable, versatile, innovative biomaterials, such as bacterial cellulose (BC), have considerable applicability potential in mixture separation methods. In the present study, a cellulose membrane produced by a symbiotic culture of bacteria and yeasts (SCOBY) was investigated with the aim of measuring the characteristics that would enable its use in the treatment of oily wastewater. BC was analyzed through physicochemical characterizations, which demonstrated its porosity (>75%), chemical structure with high cellulose content and a large quantity of intramolecular H bonds, good thermal stability with maximum degradation at temperatures close to 300 °C, high crystallinity (66%), nanofibrils of approximately 84 nm in diameter and mechanical properties that demonstrated tensile strength of up to 65.53 Mpa, stretching of approximately 18.91% and the capacity to support a compression load of around 5 kN with only the loss of free water in its structure. The characteristic data of the membranes were used for the production of a filtering module for oily mixture separation processes. This support was developed with computational fluid dynamics of finite volumes and finite element structural analysis using advanced computer-assisted engineering tools. Lastly, the conceptual, basic project of a low-cost nanofiltration module was obtained; this module could be expanded to the industrial scale, operating with several modules in parallel. [ABSTRACT FROM AUTHOR]

The growing interest in innovations regarding the treatment of oily wastewater stems from the fact that the oil industry is the largest polluter of the environment. The harm caused by this industry is seen in all countries. Companies that produce such wastewater are responsible for its treatment prior to disposal or recycling into their production processes. As oil emulsions are difficult to manage and require different types of treatment or even combined methods, a range of environmental technologies have been proposed for oil-contaminated effluents, such as gravity separation, flotation, flocculation, biological treatment, advanced oxidation processes, and membranes. Natural materials, such as biopolymers, constitute a novel, sustainable solution with considerable potential for oily effluent separation. The present review offers an overview of the treatment of oily wastewater, describing current trends and the latest applications. This review also points to further research needs and major concerns, especially with regards to sustainability, and discusses potential biotechnological applications. [ABSTRACT FROM AUTHOR]