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Plastics have quickly become one of the major pollutants in aquatic environments worldwide and solving the plastic pollution crisis is considered a central goal of modern society. In this study, 10 different plastic samples, including high‐ and low‐density polyethylene and polypropylene, were collected from a deeply polluted urban estuary in Brazil. By employing different isolation and analysis approaches to investigate plastic‐associated bacteria, a predominance of potentially pathogenic bacteria such as Acinetobacter, Aeromonas, and Vibrio was observed throughout all plastic samples. Bacteria typically found in the aquatic environment harboured clinically relevant genes encoding resistance to carbapenems (blaKPC) and colistin (such as mcr‐3 and mcr‐4), along with genetic determinants associated with potentially active gene mobilization. Whole genome sequencing and annotation of three plastic‐associated Vibrio strains further demonstrated the carriage of mobile genetic elements and antimicrobial resistance and virulence genes. On the other hand, bacteria isolated from the same samples were also able to produce esterases, lipases, and bioemulsifiers, thus highlighting that the plastisphere could also be of special interest from a biotechnological perspective. [ABSTRACT FROM AUTHOR]

In the context of a biorefinery, lignocellulosic materials represent an important source of raw material for the bioconversion of cellulose, hemicellulose, and lignin into value-added products, such as xylose for fermentation, oligosaccharides, and bioplastics for packaging. Among the most abundant lignocellulosic materials in Brazil, sugarcane bagasse biomass stands out, as it is rich in cellulose and hemicellulose. In this context, through an experimental design, this study developed a robust enzyme cocktail containing xylanases and accessory enzymes to complete the hydrolysis of xylan from sugarcane bagasse, obtaining a low xylose yield and concentration (9% and 1.8 g/L, respectively, observed in experiment number 16 from the complete hydrolysis of a xylan assay), a fermentable sugar that is important in the production of second-generation ethanol, and a high xylooligosaccharides (XOS) yield and concentration (93.1% and 19.6 g/L, respectively, obtained from a xylooligosaccharides production assay); in general, xylan has prebiotic activities that favor an improvement in intestinal functions, with immunological and antimicrobial actions and other benefits to human health. In addition to completely hydrolyzing the sugarcane bagasse xylan, this enzymatic cocktail has great potential to be applied in other sources of lignocellulosic biomass for the conversion of xylan into xylose and XOS due to its enzymes content, involving both main chain and pendant groups hydrolysis of hemicelluloses. [ABSTRACT FROM AUTHOR]

In the present work, mesoporous ZSM-5 zeolite structures were developed by means of post-synthesis modification and direct synthesis and the materials were applied as pyrolysis catalysts of different sources of plastic waste. The plastic wastes were purchased from a cooperative of selective collection, classified as polyethylene, polypropylene and polystyrene, which were used in plastic mixtures with quantities consistent with the Brazilian Association of the Plastic Industry (ABIPLAST) in order to simulate urban plastic waste in Brazil. Previously, these plastic waste mixtures were extruded with 10% m/m of catalyst and thermogravimetric analysis was performed. It was possible to observe the decrease in degradation temperatures, as well as additional degradation steps in catalytic pyrolysis compared to thermal pyrolysis. The synthesized mesoporous ZSM-5 zeolite was the catalyst with higher performance in the pyrolysis of plastic waste mixtures due to the higher proportion of strong to weak acid sites. [ABSTRACT FROM AUTHOR]

The annual production of plastics has doubled over the past 15 years and, consequently, a large amount of plastic has accumulated in the environment generating ecological problems. In this study, a Paenibacillus sp. isolate was obtained from a landfill from Brazil and it presented the alkane hydroxylase gene (alkB). Weight loss of low-density polyethylene (LDPE) was measured and a significant difference in final weight compared to initial weight was assessed. Some chemical characteristics, such as bond scissions and formation of new functional groups [carboxylic acids (3300–2500 cm−1), esters (1210–1163 cm−1), and ethers (1075–1020 cm−1)], were detected by Fourier-transform infrared spectroscopy. Bacterial colonization on the plastic surface and physical changes, as formation of cracks and pits, was visualized by scanning electron microscopy. This isolate was susceptible to all the antimicrobials tested. Therefore, this isolate possesses great potential to degrade polyethylene and become an option for LDPE bioremediation. [ABSTRACT FROM AUTHOR]

Climate change has intensified the demand for better social and environmental conservation efforts, motivating organisations to become more engaged in the development of sustainable technologies. This study analyses the innovation process in the production of green plastic, a process which replaces a non-renewable resource (naphtha) for a renewable one (ethanol from sugarcane), through the lens of sustainable supply-chain management (SSCM). An in-depth case study was conducted with a Brazilian petrochemical company, including interviews with agents of the supply chain. The results show that collaborations between the focal organisation and other agents of the supply chain are important for product development. The focal organisation has created many industry-wide initiatives, such as certification programmes and seal of quality/approval, to support the production of green plastic and reduce the social and environmental impact along the supply chain. [ABSTRACT FROM AUTHOR]

The growing demand for plastics, for packaging and consumption, is a current environmental issue. Although there are many scientific developments concerning material science, knowledge about the public's perception is low, which can delay society's efforts to face this challenge. This study aimed to understand if Brazilians who practice different sustainable actions perceive differently biodegradable, recycled, and common plastics and have different purchase intentions for each specific type of packaging. A total of 1080 Brazilian adults were first classified by their day-to-day attitudes regarding sustainability efforts. Then, their purchase intention and perception about different plastics were assessed. Regardless of sustainability practices, people associate common plastic bags with negative attributes and biodegradable plastic bags with positive attributes. This shows that there is a well-established concept about these types of bags, even if there are some misconceptions (e.g. recyclable) or controversies (e.g. non-polluting). On the other hand, results showed that consumers who adopted more sustainable practices were 3.5 times more willing to pay for biodegradable packages, even though no differences were observed in the accepted price for biodegradable bags between consumer's groups. Finally, the purchase intention comparisons for products packaged in recycled and biodegradable plastics showed the consumers were more interested in those biodegradable plastics and the purchase intention was lower for perishable food (e.g. products that can have higher safety risks). The results are important for understanding environmental policy management in Brazil, highlighting the importance to improve the population's knowledge about different types of plastic, leading to more conscious choices. • Aimed to understand if Brazilians with different sustainable practices. • Importance to improve population's knowledge about different type of plastics. • Understand the management of environmental policy in Brazil. • Consumers are more interested in purchasing products in biodegradable plastics. [ABSTRACT FROM AUTHOR]

There have been numerous discussions about plastic drinking straws and their impacts on the natural environment, reflecting on public policies and companies' operation, while alternatives to substituting plastic-based products have been proposed. However, making decisions without measuring trade-off conditions between the different scenarios may lead to higher impacts elsewhere on the life cycle or even in other areas of protection. To deepen this discussion, this paper aimed to quantify the potential environmental impacts of different drinking straws as well as find possible break-even situations. A comparative life cycle assessment (LCA) was performed to assess six different drinking straws (plastic, stainless steel, glass, paper, bamboo and jute) from cradle-to-grave. A hybrid life cycle impact assessment (LCIA) method was applied following the characterization models recommended by ILCD. Sensitivity analyses included reuse rate, washing condition, the ancillary kits usage, End-of-Life (EoL) strategies and the inclusion of an indicator to account for the marine litter impacts from Life Cycle Inventory (LCI). Results showed that for baseline scenarios, plastic drinking straws have a better environmental performance if compared to reusable straws and has a favourable performance in 10 of 11 categories if compared to paper drinking straws. Water and detergent consumptions during the use phase and the manufacturing of additional elements (bag, brush) are the main drivers for this potentially higher environmental impact. Sensitivity analyses, however, showed that certain consumption patterns may lead to a break-even situation, especially when plastic drinking straws are disposed incorrectly into the natural ecosystem. Accounting for the impacts of marine litter may lead to a change in the decision-making depending on the significance (weight) attributed to the marine litter indicator. These outcomes reinforce the importance of understanding trade-offs during the entire life cycle of products and demonstrate that policies directed to product substitution should be carefully grounded. Recommendations on reusable straws rely on simplifying their "kits", expanding reuse rates and improving the washing process. For single use straws, waste collection and correct disposal are mandatory. The lack of a LCIA methodology to account for the environmental impact of mismanaged plastic waste on ecosystems, especially in the marine compartment represents an important issue to be further developed, from which, more realistic scenarios could be outlined for any product. • The Life Cycle Assessment (LCA) of five different drinking straws was performed. • Plastic drinking straw has better environmental profile in baseline scenario. • Washing process at use phase is one of the main drivers of reusable straws. • Break-even point is possible through sensitive aspects of baseline scenario. • When mismanage plastic flow is considered decision making is affected. [ABSTRACT FROM AUTHOR]