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Plastic pellets, the pre-production form of many plastic products, undergo oxidation and photodegradation upon exposure to oxygen and sunlight, resulting in visible color changes. This study examines the impact of environmental aging on the mechanical interactions between pellet-derived microplastics and lipid bilayers, a critical component of biological membranes. Polyethylene pellets were collected from La Pineda beach near Tarragona, Spain, and categorized by chemical composition and yellowing index, an indicator of aging. The hydrophilicity of these pellets was assessed using contact angle measurements. Microplastics were produced by grinding and filtering these pellets and subsequently dispersed around a free-standing lipid bilayer within a 3D microfluidic chip to investigate their interactions. Our results reveal that aged microplastics exhibit a significantly increased adhesive interaction with lipid bilayers, leading to greater bilayer stretching. Theoretical modeling indicates a linear relationship between the adhesive interaction and the contact angle of the pellets, reflecting their hydrophilicity. These findings emphasize the increased mechanical impact of aged microplastics on biological membranes, which raises concerns about their potential toxicological effects on living organisms. This study highlights the importance of understanding the interactions between environmentally aged microplastics and biological systems to assess their risks, as these may differ significantly from pristine microplastics often studied under laboratory conditions. [ABSTRACT FROM AUTHOR]

UNLABELLED: Biodegradable plastics are urgently needed to replace petroleum-derived polymeric materials and prevent their accumulation in the environment. To this end, we isolated and characterized a halophilic and alkaliphilic bacterium from the Great Salt Lake in Utah. The isolate was identified as a Halomonas species and designated CUBES01. Full-genome sequencing and genomic reconstruction revealed the unique genetic traits and metabolic capabilities of the strain, including the common polyhydroxyalkanoate (PHA) biosynthesis pathway. Fluorescence staining identified intracellular polyester granules that accumulated predominantly during the strains exponential growth, a feature rarely found among natural PHA producers. CUBES01 was found to metabolize a range of renewable carbon feedstocks, including glucosamine and acetyl-glucosamine, as well as sucrose, glucose, fructose, and further glycerol, propionate, and acetate. Depending on the substrate, the strain accumulated up to ~60% of its biomass (dry wt/wt) in poly(3-hydroxybutyrate), while reaching a doubling time of 1.7 h at 30°C and an optimum osmolarity of 1 M sodium chloride and a pH of 8.8. The physiological preferences of the strain may not only enable long-term aseptic cultivation but also facilitate the release of intracellular products through osmolysis. The development of a minimal medium also allowed the estimation of maximum polyhydroxybutyrate production rates, which were projected to exceed 5 g/h. Finally, also, the genetic tractability of the strain was assessed in conjugation experiments: two orthogonal plasmid vectors were stable in the heterologous host, thereby opening the possibility of genetic engineering through the introduction of foreign genes. IMPORTANCE: The urgent need for renewable replacements for synthetic materials may be addressed through microbial biotechnology. To simplify the large-scale implementation of such bio-processes, robust cell factories that can utilize sustainable and widely available feedstocks are pivotal. To this end, non-axenic growth-associated production could reduce operational costs and enhance biomass productivity, thereby improving commercial competitiveness. Another major cost factor is downstream processing, especially in the case of intracellular products, such as bio-polyesters. Simplified cell-lysis strategies could also further improve economic viability.

Fumarate is an unsaturated dicarboxylic acid useful as a raw material for unsaturated polyester resins, polybutylene succinate (PBS), poly(propylene fumarate) (PPF), plasticisers, and other products. Biodegradable plastics derived from fumarate are an attractive solution to the serious environmental pollution caused by plastic disposal. A new fumarate production from CO2 and biobased pyruvate using enzymes in aqueous media under ambient temperature and pressure is an environmental approach to overcome plastic pollution and achieve CO2 capture, utilization and storage (CCUS). In this work, fumarate production from pyruvate and low-concentration CO2 below 15% captured from the gas phase using 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES)-NaOH buffer solution with a multi-enzyme system consisting of pyruvate carboxylase from a bovine liver (PC; EC 6.4.1.1), recombinant malate dehydrogenase from bacteria (MDH; EC 1.1.1.37) and fumarase from a porcine heart (FUM; EC 1.1.1.37) in the presence of adenosine 5′-triphosphate (ATP) and NADH was investigated. It was found that pyruvate can be converted into L -malate in high yields (more than 80%) directly using 15% CO2 equivalent to exhaust gas as a carboxylating agent using a dual-enzyme system consisting of PC and MDH in the presence of ATP and NADH after 5 h incubation. Moreover, fumarate production from 15% CO2 and pyruvate as raw materials was accomplished using a dual-enzyme system consisting of PC and MDH. [ABSTRACT FROM AUTHOR]

The depletion of global petrochemical resources, coupled with the environmental challenges arising from the extensive use of traditional plastics, has led to greater interest in the research of environmentally friendly biodegradable materials that can be used in various applications. The weak water barrier properties of collagen hydrolysate (CH) obtained from leather industry trimming waste seriously limit its practical application areas. In this study, CH/sodium alginate (CH/SA)-based films were produced using the solution casting method because they are non-toxic and biocompatible. The CH/SA composition with the best water barrier property was selected and cross-linked with transglutaminase (TG), genipin (GP), and tannic acid (TA). Cross-linking significantly increases the mechanical strength, thermal ability, and hydrophobicity of the films, thereby reducing their WVP and WS. The film sample CH40/SA60/GP0.4%, out of all the examined specimens, demonstrated superior overall performance, characterized by a TS of 21.209 MPa and a WS of 19.896%. The results indicate that biodegradable films serve as a promising foundation for the development of packaging materials. Consequently, this study offers an effective approach to creating high-performance, environmentally friendly, and degradable CH/SA-based films and products. [ABSTRACT FROM AUTHOR]

Petroleum-derived single-use plastics have dominated a range of material applications, including packaging and service ware (e.g., water bottles, food containers, and drinking straws). However, despite their short-lived service life, the inherent durability, and stability of these plastics have resulted in significant environmental accumulation and spill, contaminating both aquatic and land ecosystems. Consequently, there is a surging interest in the development of bioplastics as a sustainable alternative to petrochemical derived plastics that align with circular economy principles. Among potential materials, cellulose acetate (CA) showcases impressive mechanical properties, optical characteristics, melt processability, and compostability. However, due to its hygroscopic behavior, inferior barrier properties, and lack of dimensional stability, CA applications in the packaging industry are minimal. In this research, the acetylation of lignin and its use as a functional filler for CA matrix was studied. The impact of varying lignin loadings (up to 30 wt.%) on the tensile, morphological, barrier, and viscoelastic properties of the resulting materials was investigated. A thorough characterization of the compression-molded acetylated lignin-CA films revealed a reduction in water uptake (by 59% over baseline), up to a 41.5% reduction in water vapor permeability, and enhanced tensile properties with melt flowability. In summary, the examined films displayed favorable characteristics for use in food and other packaging applications. Consequently, they serve as low carbon footprint, and eco-friendly substitutes for conventional petrochemical-based packaging materials. [ABSTRACT FROM AUTHOR]

Poly(butylene adipate‐co‐terephthalate) (PBAT) is popular because of its low cost, biodegradability, good processing properties, flexibility, and mechanical features. In this study, we explore the potential of PBAT‐based bioplastics by adding AgVO3 nanorods with PBAT to reduce costs. We produced nanocomposite films of PBAT reinforced with 1, 3, and 5 wt% of AgVO3 nanorods using solvent casting. The inclusion of AgVO3 in the structure of PBAT was investigated through Fourier transform infrared spectroscopy, x‐ray diffraction, and scanning electron microscopy. The nanocomposite films demonstrate excellent properties, surpassing those of single‐component blends, enhancing mechanical properties, and improving the barrier properties of nanocomposite films. The water vapor transmission rate of AgVO3 reinforced (5 wt%) nanocomposite films improved by 42.45% compared to pure PBAT films. The tensile strength of the PBA‐3 film was 37.19 MPa, exhibiting higher strength than the films produced from clean PBAT (19.73 MPa). The AgVO3‐reinforced films demonstrated increased resistance to moisture and water, as indicated by their higher water contact angle values (88.04°). Food‐borne bacteria like Staphylococcus aureus and Escherichia coli have been stable to the antibacterial activity of the nanocomposites on the addition of AgVO3.The potential applications of these nanocomposite films in food packaging are promising, offering a sustainable and effective solution to food preservation. Highlights: The AgVO3‐filled poly(butylene adipate‐co‐terephthalate) (PBAT) nanocomposite films exhibit superior mechanical, barrier, and resistance to moisture and water compared to neat PBAT films.The water vapor transmission rate of the film is significantly enhanced, with a 42.45% enhancement in films reinforced with 5 wt% AgVO3.AgVO3‐filled PBAT nanocomposites demonstrate effective antibacterial activity against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

The pressing need to mitigate climate change and drastically reduce environmental pollution and loss of biodiversity has precipitated a so-called energy transition aimed at the decarbonization of energy and defossilization of the chemical industry. The goal is a carbon-neutral (net-zero) society driven by sustainable energy and a circular bio-based economy relying on renewable biomass as the raw material. It will involve the use of green carbon, defined as carbon derived from terrestrial or aquatic biomass or organic waste, including carbon dioxide and methane emissions. It will also necessitate the accompanying use of green hydrogen that is generated by electrolysis of water using a sustainable source of energy, e.g. solar, wind or nuclear. Ninety per cent of the industrial chemicals produced in oil refineries are industrial monomers that constitute the precursors of a large variety of polymers, many of which are plastics. Primary examples of the latter are polyolefins such as polyethylene, polypropylene, polyvinyl chloride and polystyrene. Polyolefins are extremely difficult to recycle back to the olefin monomers and discarded polyolefin plastics generally end up as the plastic waste that is responsible for the degradation of our natural habitat. By contrast, waste biomass, such as the lignocellulose contained in forestry residues and agricultural waste, constitutes a renewable feedstock for the sustainable production of industrial monomers and the corresponding polymers. The latter could be the same polyolefins that are currently produced in oil refineries but a more attractive long-term alternative is to produce polyesters and polyamides that can be recycled back to the original monomers: a paradigm shift to a truly bio-based circular economy on the road to a net-zero chemical industry. This article is part of the discussion meeting issue 'Green carbon for the chemical industry of the future'. [ABSTRACT FROM AUTHOR]

Highlights Biodegradable biobased polymers are a promising solution to reduce the dependence on conventional plastics and minimize their environmental impact. This work evaluated the recycling capacity of a biodegradable polymer (MaterBi) and its composite with agave fibers. The materials were reprocessed by several cycles using compression molding. Service life simulation was performed using accelerated weathering. Samples from each reprocessing cycle were characterized in terms of melt flow index (MFI), color, porosity, water absorption, compostability, and mechanical and thermal properties. The MFI of MaterBi increased with each cycle, going from 3.5 to 95 g/10 min for the first to sixth cycles and from 2 to 117 g/10 min for the first and fourth cycles for the biocomposite. Reprocessing produced chain scission and modified the thermal and mechanical properties. MaterBi exhibited competitive mechanical properties compared to conventional polymers, even after four reprocessing cycles (tensile, flexural, and impact strengths of 27, 55 MPa, and 30 J/m). Besides potential cost reductions, the agave fiber addition positively affected the tensile and flexural modulus, which remained after the fourth cycle in 1100 and 2300 MPa. The results confirmed that MaterBi and its biocomposites can be recycled for several cycles, extending their useful life before final biodegradation. MaterBi (MB) and its agave fiber biocomposites are suitable for reprocessing. MB tensile and flexural properties remained stable after four reprocessing cycles. Agave fibers make MB more prone to weathering, impacting its properties. MB and its biocomposites degrade in water and compost conditions. [ABSTRACT FROM AUTHOR]

Despite the urgent need for accurate and robust observations of microplastics in the marine environment to assess current and future environmental risks, existing procedures remain labour-intensive, especially for smaller-sized microplastics. In addition to this, microplastic analysis faces challenges due to environmental weathering, impacting the reliability of research relying on pristine plastics. This study addresses these knowledge gaps by testing the robustness of two automated analysis techniques which combine machine learning algorithms with fluorescent colouration of Nile red (NR)-stained particles. Heterogeneously shaped uncoloured microplastics of various polymers—polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC)—ranging from 100 to 1000 µm in size and weathered under semi-controlled surface and deep-sea conditions, were stained with NR and imaged using fluorescence stereomicroscopy. This study assessed and compared the accuracy of decision tree (DT) and random forest (RF) models in detecting and identifying these weathered plastics. Additionally, their analysis time and model complexity were evaluated, as well as the lower size limit (2–4 µm) and the interoperability of the approach. Decision tree and RF models were comparably accurate in detecting and identifying pristine plastic polymers (both > 90%). For the detection of weathered microplastics, both yielded sufficiently high accuracies (> 77%), although only RF models were reliable for polymer identification (> 70%), except for PET particles. The RF models showed an accuracy > 90% for particle predictions based on 12–30 pixels, which translated to microplastics sized < 10 µm. Although the RF classifier did not produce consistent results across different labs, the inherent flexibility of the method allows for its swift adaptation and optimisation, ensuring the possibility to fine-tune the method to specific research goals through customised datasets, thereby strengthening its robustness. The developed method is particularly relevant due to its ability to accurately analyse microplastics weathered under various marine conditions, as well as ecotoxicologically relevant microplastic sizes, making it highly applicable to real-world environmental samples. [ABSTRACT FROM AUTHOR]

Knowledge on the variation of yield and water use efficiency under different mulching methods is important for guiding rained maize production in the Loess Plateau area. In this study, eight different plastic film mulching methods was established to analyze the maize growth, soil water content and soil temperature changes of dryland maize, and increase yield and water use efficiency (WUE). The field experiment was conducted in 2019, and eight treatments were set up, including a traditional flat planting without mulching (CK), ridge-furrow with ridges mulching black plastic film and furrows mulching straw (HJ), ridge-furrow with ridges mulching black plastic film and furrows bare (HL), ridge-furrow with ridges mulching liquid plastic film and furrows mulching straw (YJ), ridge-furrow with ridges mulching liquid plastic film and furrows bare (YL), ridge-furrow with ridges mulching biodegradable plastic film and furrows mulching straw (SJ), ridge-furrow with ridges mulching biodegradable plastic film and furrows bare (SL) and ridge-furrow with ridges bare and furrows mulching straw (NJ). Furthermore, the AHP-TOPSIS was employed to evaluate the optimal mulching method for maize. The results showed that compared with CK and NJ treatment, the soil water content and soil storage were significantly changes with other treatments in the reproductive period of maize. Among the six mulching methods, maize yield in HJ, HL, YJ, YL, SJ, and SL treatments were 46.28%, 61.95%, 70.30%, 51.02%, 52.02% and 53.53% significantly greater than CK treatment. In addition, dryland maize WUE was 66.53% and 84.01% higher in the YJ and YL treatments with ridges mulching liquid plastic film than in the CK treatment, respectively. The optimal treatments of economic benefits were YL and HJ. Through AHP-TOPSIS comprehensive analysis, the optimal mulching methods were YL and HJ treatment. Current field trials indicate that YL treatment could serve as a promising option to improve dryland maize yield, WUE, and reducing environmental risks in the Loess Plateau of China. [ABSTRACT FROM AUTHOR]

Plastic waste and wastewater are indeed significant environmental issues that have wide‐ranging impacts on ecosystems, human health, and the economy. This study outlines the synthesis of biodegradable polyvinyl alcohol (PVA)–starch polymeric films incorporating multiwalled carbon nanotubes (MWCNTs) derived from plastic waste and unzipped carbon nanotubes oxides (UMCNOs) as co‐filled nanomaterials. These films were formulated based on data generated using a mixture design method in Design Expert 13 software, resulting in the synthesis of 19 films utilizing five types of PVA–starch polymer solutions (Types A–E). The synthesized films underwent characterization to study their surface morphology via scanning electron microscope and Fourier transform infrared spectroscopy analysis. Subsequently, the films were individually subjected to vacuum filtration, through which cationic dyes such as methylene blue (MB) and anionic dye Congo red (CR) were passed in batches. The highest removal efficiency of 96.43% for MB dye was achieved, accompanied by an exceptionally high flux of 3146.78 LMH. Similarly, the maximum removal of 88.08% for CR was observed with a flux of 1512.66 LMH. The renewable active sites mechanism resulted in increased dye removal with every cycle. Results indicated efficient reusability, particularly when washed with ethanol–water solution. [ABSTRACT FROM AUTHOR]

The use of biodegradable plastics has been proposed as an alternative to mitigate the pollution problem caused by traditional non‐biodegradable plastics. However, the relative impacts of both types of microplastics on plant community productivity and diversity is not known. Moreover, it is unclear whether soil biota can differentially mediate the impacts of biodegradable and non‐biodegradable microplastics on plant communities.In this study, we investigated the effects of biodegradable and non‐biodegradable microplastics on plant community biomass production and diversity, and whether soil biota mediate these effects. We employed a fully crossed factorial design, growing six plant communities in the presence or absence of 10 individual microplastics, and in live soil versus sterilized soil. We hypothesized that: (1) Biodegradable microplastics have a less negative effect on plant community biomass production and diversity compared to non‐biodegradable microplastics. (2) Soil biota differentially mediate the effects of biodegradable and non‐biodegradable microplastics on plant community biomass production and diversity.Statistical analyses that included all 10 microplastics yielded two main findings. First, live soil ameliorated the negative effects of biodegradable microplastics on community shoot biomass. Second, the presence of microplastics, rather than their biodegradability, significantly reduced community diversity. Separate analyses of individual microplastics suggest that these patterns were driven by specific microplastics. The biodegradable microplastic polybutylene succinate (PBS) was the main driver of the pattern observed in community shoot biomass. In contrast, the biodegradable microplastic polycaprolactone (PCL) and non‐biodegradable microplastics ethylene‐vinyl acetate (EVA) and polyvinyl chloride (PVC) were the main drivers of the pattern observed in community diversity. Further analyses excluding PBS from the global models, but including the other nine microplastics, revealed no significant differences in community shoot biomass and diversity between biodegradable and non‐biodegradable microplastics in live versus sterilized soil.Synthesis and applications. Our findings suggest that biodegradable microplastics, often considered environmentally friendly, are not necessarily less harmful than non‐biodegradable microplastics to the growth and diversity of plant communities. Some individual biodegradable microplastics, such as PBS, still pose significant ecological risks to plant community structure and productivity. However, the results also suggest that soil biota may mitigate the negative effects of some biodegradable microplastics. [ABSTRACT FROM AUTHOR]

The mounting global concern over the environmental consequences of petroleum-based plastics has prompted significant research into sustainable alternatives, with bioplastics emerging as a forerunning solution. This systematic review elucidates the multifaceted synthesis processes of bioplastics, which are derived from renewable sources such as plant starches, cellulose, and waste materials. The synthesis encompasses stages from raw material selection, pre-treatment, to the incorporation of various additives, with the aim to achieve specific properties in the resultant bioplastics. A substantial focus of this review lies in comprehensively understanding the role of additives, which serve as the pivotal agents in tailoring the mechanical and thermal characteristics of bioplastics. Additives, including cross-linking agents, plasticizers, fillers, compatibilizers, and reinforcement agents, are critically examined for their influence on attributes such as tensile strength, flexibility, thermal stability, and biodegradability. Factors such as intermolecular interactions, hydrogen bonding, and moisture content, play a determining role towards the resultant properties. The prospects for bioplastics are rapidly expanding, signalling a transformative shift in various applications ranging from eco-friendly packaging to advanced biomedical devices. This article serves as a comprehensive guide to both researchers and industry stakeholders, providing deep insights into the synthesis of bioplastics and the transformative role additives play in their functional properties. [ABSTRACT FROM AUTHOR]

The extensive use of non-biodegradable and petroleum derived polymers in industry exacerbates environmental problems associated with plastic waste accumulation and fossil resource depletion. The most promising solution to overcome this issue is the replacement of these polymers with biodegradable and bio-based polymers. In this paper, novel biocomposites were prepared from bio-based polyamide 5.6 (PA56) with the addition of olive stone powder (OSP) at varying weight concentrations by melt compounding method. The degradability of the prepared biocomposites is investigated through soil burial test, and assessed by reduction in their mechanical properties. The biodegradability of bio-based polyamide 5.6 is shown to be improved by addition of olive stone powder, and its effects on the properties of polymer matrix are elucidated. The Fourier transform infrared (FTIR) spectrum of the biocomposites indicate the successful incorporation of OSP into PA56 polymer matrix. After six-month soil burial test, scanning electron microscopy and FTIR show the degradation of PA56 through morphological and structural changes, respectively. Differential scanning calorimetry reveals the changes in the transition temperatures of the polymer matrix and an increase in crystallinity. Thermogravimetric analysis is used on the biocomposite to determine the fraction of its components, polymer and biofiller, and the results show that 2.67% (w/w) of the polyamide 5.6 is biodegraded at the end of the six-month soil burial. [ABSTRACT FROM AUTHOR]

Plastic waste has been gradually accumulating in the environment due to rapid population growth and increasing consumer demand, posing threats to both the environment and human health. In this overview, we provide a comprehensive understanding of the degradation of plastics in real environments, such as soil, aquatic environment, landfill, and compost. Both conventional and biodegradable plastics exhibit limited degradation in real environments, except for biodegradable plastics during industrial composting with high thermophilic temperatures. Meanwhile, we also review techniques for enhanced degradation of plastics such as physical technologies (e.g., photocatalysis, mechanical degradation, and pyrolysis), chemical technologies (e.g., hydrolysis, alcoholysis, ammonia, strong oxidation, and supercritical fluids), and biotechnologies (e.g., microorganisms, microfauna, and microalgae). The future research directions for the enhancement of plastic degradation are also discussed, such as the establishment of equivalency standards, adoption of internal control techniques, the control of precise recycling of plastic products, and the ecotoxicology of their degradation products. Therefore, this review comprehensively summarizes the state of plastic degradation in real environments and proposes methods to improve plastic degradation, providing a theoretical basis for the future control and disposal of plastics. [ABSTRACT FROM AUTHOR]

The use of bioplastics is a new strategy for reducing microplastic (MP) waste caused by petroleum‐based plastics. This problem has received increased attention worldwide, leading to the development of large‐scale bioplastic plants. The large amount of MPs in aquatic and terrestrial environments and the atmosphere has raised global concern. This article delves into the profound environmental impact of the increasing use of petroleum‐based plastics, which contribute significantly to plastic waste and, as a consequence, to the increase in MPs. We conducted a comprehensive analysis to identify countries that are at the forefront of efforts to produce bioplastics to reduce MP pollution. In this article, we explain the development, degradation processes, and research trends of bioplastics derived from biological materials such as starch, chitin, chitosan, and polylactic acid (PLA). The findings pinpoint the top 10 countries demonstrating a strong commitment to reducing MP pollution through bioplastics. These nations included the United States, China, Spain, Canada, Italy, India, the United Kingdom, Malaysia, Belgium, and the Netherlands. This study underscores the technical and economic obstacles to large‐scale bioplastic production. Integr Environ Assess Manag 2024;20:1892–1911. © 2024 SETAC Key Points: Microplastics (MP) have caused concern due to their environmental effects, potential to release plastic monomers, affinity for chemical interactions, and potential to enter aquaculture and fishery production.The findings pinpoint the top 10 countries demonstrating a strong commitment to reducing MP pollution by replacing petroleum‐based plastics with bioplastics.Using bibliometric techniques, we mapped and identified the countries that were most actively engaged in shifting to bioplastic production during the period 2001–2021.This article focuses on starch‐based bioplastics used primarily in food packaging, increasing their mechanical properties by adding fibers, and extending the shelf life of food with antibacterial nanoparticles. [ABSTRACT FROM AUTHOR]

Environmental contamination by plastics poses a significant threat to both fauna and flora, manifesting in lethal and sub-lethal effects. Plastics can enter coastal and marine environments through wind and rain, with microplastics (< 5 mm; MPs) arising from the degradation of larger plastics or being manufactured for commercial use. Despite Brazil's extensive coastline, data on microplastic contamination is scarce. This study aimed to assess microplastic pollution on a beach in Rio Grande do Sul, Brazil. Samples were collected from 30 points along the high tide line, with beach sand processed through density separation and filtration. Microplastics were quantified using Nile Red stain under fluorescence microscopy and chemically identified via the µRaman technique. Results showed an average concentration of 650 MPs/kg of sediment, with higher concentrations near the Mampituba River, indicating a greater transport of plastic contaminants by the river to the coastline. The smallest particles (50–100 µm) were most abundant, and the predominant types of plastics identified were polyethylene (PE), polypropylene (PP), and polyamide (PA). This study provides the first quantification of microplastic pollution in this region, indicating that the concentration and types of microplastics are consistent with findings elsewhere in Brazil and globally. These results highlight the widespread nature of microplastic pollution and underscore the need for coordinated environmental remediation efforts. [ABSTRACT FROM AUTHOR]

Exploring microorganisms with downstream synthetic advantages in lignin valorization is an effective strategy to increase target product diversity and yield. This study ingeniously engineers the non-lignin-degrading bacterium Ralstonia eutropha H16 (also known as Cupriavidus necator H16) to convert lignin, a typically underutilized by-product of biorefinery, into valuable bioplastic polyhydroxybutyrate (PHB). The aromatic metabolism capacities of R. eutropha H16 for different lignin-derived aromatics (LDAs) are systematically characterized and complemented by integrating robust functional modules including O-demethylation, aromatic aldehyde metabolism and the mitigation of by-product inhibition. A pivotal discovery is the regulatory element PcaQ, which is highly responsive to the aromatic hub metabolite protocatechuic acid during lignin degradation. Based on the computer-aided design of PcaQ, we develop a hub metabolite-based autoregulation (HMA) system. This system can control the functional genes expression in response to heterologous LDAs and enhance metabolism efficiency. Multi-module genome integration and directed evolution further fortify the strain's stability and lignin conversion capacities, leading to PHB production titer of 2.38 g/L using heterologous LDAs as sole carbon source. This work not only marks a leap in bioplastic production from lignin components but also provides a strategy to redesign the non-LDAs-degrading microbes for efficient lignin valorization. One challenge in lignin valorization is that microorganisms possessing downstream metabolic advantages are unable to convert lignin. Here, the authors engineer the non-lignin-degrading bacterium Ralstonia eutropha to efficiently convert lignin into polyhydroxybutyrate using a self-enhanced autoregulation system. [ABSTRACT FROM AUTHOR]

To access degradable polyolefin plastic, non‐alternating copolymerization of ethylene (E) and carbon monoxide (CO) for producing polyethylene (PE) with in‐chain ketones is particularly appealing; however, it still presents significant challenges such as molecular weight modulation (hydrogen response) and chain endgroup control (functional terminal). In this study, we achieved hydrogen‐controlled E/CO non‐alternating copolymerization using late transition metal catalysts. This process results in linear PEs containing the desired non‐alternating in‐chain keto groups (1.0–9.3 mol %) and with tunable molecular weights ranging from 43 to 195 kDa. In this reaction, H2 serves as a chain transfer agent, modulating the polymer's molecular weight, forming unique aldehyde endgroups and eliminating usual olefinic endgroups; CO undergoes non‐alternating insertion into the PE chain, resulting in a strictly non‐alternating structure (>99 %) for the keto‐PE. The dispersed incorporation of in‐chain keto groups retains bulk properties of PE and makes PE susceptible to photodegradation, which produces significantly lower molecular weight polymers and oligomers with unambiguous vinyl and acetyl terminals. [ABSTRACT FROM AUTHOR]

Biodegradable polymers are gaining attention as alternatives to non‐biodegradable plastics to address environmental issues. With the rising global demand for plastic products, the development of non‐toxic, biodegradable plastics is a significant topic of research. Aliphatic polyester, the most common biodegradable polyester, is notable for its semi‐crystalline structure and can be synthesized from fossil fuels, microbial fermentation, and plants. Due to great properties like being lightweight, biodegradable, biocompatible, and non‐toxic, aliphatic polyesters are used in packaging, medical, agricultural, wearable devices, sensors, and textile applications. The biodegradation rate, crucial for biodegradable polymers, is discussed in this review as it is influenced by their structural properties and environmental conditions. This review discusses currently available biodegradable polyesters, their emerging applications, and the challenges in their commercialization. As research in this area grows, this review emphasizes the innovation in biodegradable aliphatic polyesters and their role in advancing environmental sustainability. [ABSTRACT FROM AUTHOR]

As environmental problems increase, disposable products are being replaced and recommended with materials with a low environmental load when it discarded. So the demand for bioplastics for building a sustainable society is increasing. This study focuses mainly on the applicability of biodegradable plastics and rosin maleic resin (RMR, DX‐250) blends with potential use in eco‐friendly hot‐melt adhesives (HMA). Poly (butylene adipate‐co‐terephthalate) (PBAT), which has high dimensional stability owing to low crystallinity, is used as the main polymer of the HMA. And rosin maleic resin, which is effective for increasing adhesive properties and compatibility as a tackifier. The HMA based on PBAT and RMR blends are prepared via melt‐blend extrusion. Compatibility and wettability are increased under the influence of RMR, and adhesion properties are improved, compared to that of PBAT. In addition, as confirmed polarizing microscope (POM), the addition of RMR leads to a decrease in crystallinity, which can be expected to be effective for biodegradation. This result PBAT/RMR 7/3 blend significantly enhances the adhesion strength of PBAT from 1.8 to 7.3 MPa. Therefore, PBAT with the blends containing 30 wt.% of RMR has considerable potential application in the HMA field. [ABSTRACT FROM AUTHOR]

Medical plastic-appliance-based healthcare services, especially in dentistry, generate tremendous amounts of plastic waste. Given the physiological features of our mouth, it is desirable to substitute dental care plastics with viscoelastic and antimicrobial bioplastics. Herein, we develop a medical-grade and sustainable bioplastic that is viscoelastic enough to align the tooth positions, resists microbial contamination, and exhibits recyclable life cycles. In particular, we devise a molecular template involving entanglement-inducing and antimicrobial groups and prepare a silk fibroin-based dental care bioplastic. The generated compactly entangled structure endows great flexibility, toughness, and viscoelasticity. Therefore, a satisfactory orthodontic outcome is accomplished, as demonstrated by the progressive alignment of male rabbit incisors within the 2.5 mm range. Moreover, the prepared bioplastic exhibits resistance to pathogenic colonization of intraoral microbes such as Streptococcaceae and Veillonellaceae. Because the disentanglement of entangled domains enables selective separation and extraction of the components, the bioplastic can be recycled into a mechanically identical one. The proposed medical-grade and sustainable bioplastic could potentially contribute to a green healthcare future. Medical plastic-appliance-based healthcare services, especially in dentistry, generate large amounts of plastic waste. Here, the authors address this issue by developing a medical-grade and sustainable bioplastic that is viscoelastic enough to align the tooth positions, resists microbial contamination, and exhibits recyclable life cycles. [ABSTRACT FROM AUTHOR]

As one of the mainstream biodegradable materials, poly(butylene adipate-co-terephthalate) (PBAT) foams offer a sustainable alternative to traditional plastic foams, effectively reducing environmental pollution. However, the high cost and poor mechanical performance of PBAT foams impede their practical application. Herein, the glycidyl methacrylate-grafted biomass lignin (GML) was used to produce a PBAT/GML composite foam with good foaming performance and mechanical properties at high lignin-filling amounts by twin-screw melting free radical polymerization and supercritical CO2 foaming process. The compatibility of GML in the PBAT matrix was improved due to the formation of ester bonds in modified lignin, endowing the PBAT/GML (PGML) composite foam with exceptional foaming performance. Additionally, the mechanical properties of PGML composite foam were remarkably enhanced due to the introduction of the abundant aromatic structures of GML and the construction of a stable covalent crosslinking network. The compressive strengths and compression modulus of the PGML foam were improved by 2.53 times and 2.47 times, while its bending strength and bending modulus were improved by 1.27 times and 3.92 times compared to the neat PBAT. This research affords a new strategy for developing low-cost biodegradable biomass PBAT/lignin composite foam materials with good foaming performance and mechanical properties. [ABSTRACT FROM AUTHOR]

Biodegradable polymers are getting attention as renewable alternatives to petroleum-based plastics due to their environmental benefits. However, improving their physical properties remains challenging. In this work, biodegradable biopolymers (PVA-PCD) were fabricated by chemically crosslinking petroleum-based polyvinyl alcohol (PVA) with biomass-derived cardanol-based polyols (PCD). Biopolymers were characterized using various techniques, including Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and swelling tests. Cardanol, the raw material, was converted into polyols via epoxidation followed by hydroxylation. FT-IR analysis confirmed that PVA-PCD biopolymers were crosslinked between the hydroxyl groups of PVA and PCD and the aldehydes of crosslinker glutaraldehyde (GLU), accompanied by the formation of acetal groups with ether bridges. XRD showed that the crystallinity of crosslinked polymers decreased, indicating that crosslinking occurs disorderly. TGA exhibited that GLU significantly improved the thermal stabilities of PVA and PCD-PVA polymers, as evidenced by increased decomposition temperatures. On the other hand, the effect of PVA/PCD ratios was minor on biopolymers' thermal stabilities. Swelling tests revealed that increased crosslinking density decreased the swelling ratio, suggesting that PVA-PCD biopolymers become more hydrophobic with high brittleness, high strength, and low swelling capacity. In summary, this study demonstrates that PVA-PCD biopolymers fabricated from biomass-derived materials have potential for various applications, such as biodegradable materials and sustainable packaging. [ABSTRACT FROM AUTHOR]

In this study, polylactic acid (PLA) is compounded with cottonseed protein concentrate (CPC) by melt blending under the compatibilization of maleic anhydride (MA), and then hot‐pressed to prepare PLA/CPC composite bioplastics. The attenuated total reflection Fourier transform infrared (ATR‐FTIR) spectroscopy showed that high temperature and compatibilizer induced the protein secondary structure to transition. CPC can be used as a heterogeneous PLA nucleating agent, effectively accelerating PLA crystallization, which is characterized by polarization optical microscopy (POM), synchrotron radiation wide‐angle X‐ray scattering (WAXS) and differential scanning calorimetry (DSC). The highest crystallinity of the PLA/CPC10 composite is 8.9% higher than that of neat PLA. The unfolding of the protein secondary structure is likely to promote an orderly arrangement of PLA crystals, showing strong binding forces between them. Moreover, the CPC/PLA interfacial compatibility is improved by the addition of a small amount of maleic anhydride. The increased crystallinity and interfacial compatibility contribute to the improved mechanical properties, water resistance, and thermal stability of the bioplastics. Environmentally friendly plastic handicrafts (e.g., commemorative emblems, flower pots, ornaments, etc.) can be fabricated using these biocomposites for future value‐added applications. [ABSTRACT FROM AUTHOR]

Food packaging, which is typically made of paper/cardboard, glass, metal, and plastic, is essential for protecting and preserving food. However, the impact of conventional food packaging and especially the predominant use of plastics, due to their versatility and low cost, bring serious environmental and health problems such as pollution by micro and nanoplastics. In response to these challenges, biotechnology emerges as a new way for improving packaging by providing biopolymers as sustainable alternatives. In this context, bacterial cellulose (BC), a biodegradable and biocompatible material produced by bacteria, stands out for its mechanical resistance, food preservation capacity, and rapid degradation and is a promising solution for replacing plastics. However, despite its advantages, large-scale application still encounters technical and economic challenges. These include high costs compared to when conventional materials are used, difficulties in standardizing membrane production through microbial methods, and challenges in optimizing cultivation and production processes, so further studies are necessary to ensure food safety and industrial viability. Thus, this review provides an overview of the impacts of conventional packaging. It discusses the development of biodegradable packaging, highlighting BC as a promising biopolymer. Additionally, it explores biotechnological techniques for the development of innovative packaging through structural modifications of BC, as well as ways to optimize its production process. The study also emphasizes the importance of these solutions in promoting a circular economy within the food industry and reducing its environmental impact. [ABSTRACT FROM AUTHOR]

This study aims to enhance the properties of biodegradable plastics by blending poly(lactic acid) (PLA) as well as poly(butylene succinate) (PBS) with silicon carbide (SiC). SiC content was varied from 10 to 40 phr using an internal mixer, maintaining a 90/10 wt% ratio of PLA/PBS as the matrix. The investigation covered mechanical, thermal properties, chemical structure, and composite morphology. The morphological analysis confirmed even dispersion of SiC within the PLA/PBS matrix, possibly due to improved compatibility via a silane coupling treatment. This resulted in the maximum Young's modulus and impact strength with 40 phr SiC, showing a 40% and 76% enhancement, respectively, compared to pure PLA. Concerning thermal properties, SiC addition influenced the mobility of PLA/PBS molecular chains and crystalline structure, leading to an increase in Tg with higher SiC fractions. However, ΔHm of PLA, PBS, and Xc,PLA decreased, which corresponds to reduced viscosity in the PLA/PBS blend and increased mobility with higher SiC content, as indicated by the elevated MFI value. Highlights: Young's modulus increased by 40% and impact strength by 76% than pure PLA.Even SiC dispersion in PLA/PBS, possibly aided by silane coupling.SiC alters chain mobility, boosts crystalline structure, raising Tg.ΔHm and Xc,PLA reduced, suggests reduced viscosity in PLA/PBS at more SiC.Elevated MFI value shows increased chain mobility in PLA/PBS blend at more SiC. [ABSTRACT FROM AUTHOR]

Bio‐based polymers may present a sustainable, circular way to reduce the environmental impact of plastics because they are produced from biomass that absorbs CO2 during its growth. However, sourcing (type of biomass used and cultivation location), production, and end‐of‐life affect the environmental impact of bio‐based plastics. We assessed the effect of sourcing and end‐of‐life options on the environmental impact of bio‐based high‐density polyethylene (bio‐HDPE) in 31 sourcing scenarios and five end‐of‐life options. Our study found that careful consideration of biomass sourcing (biomass type and production location) and end‐of‐life is needed to optimize the environmental impact of bio‐based plastics. If these aspects are not considered, the environmental impact of bio‐HDPE may exceed that of its petrochemical‐based counterpart. The direct availability of fermentable sugars indicated a lower environmental impact. The production location affected the resources needed for biomass cultivation and the environmental impact of processing due to the energy mix. Recently published guidelines do not allow biogenic carbon to be accounted for during the production stage, but only upon the incineration of the plastic. Our results show that this way of attributing biogenic carbon results in an apparent disadvantage for bio‐based plastics compared to petrochemical‐based plastics. Furthermore, it disadvantaged mechanical recycling of bio‐based plastics compared to incineration, a result out of line with circular economy principles. [ABSTRACT FROM AUTHOR]

As a model of a chemical upcycling process, we have developed a single-metal homogeneous catalytic system to break down persistent polyethylene waste into valuable chemical intermediates. This could ultimately be used to produce important chemical products, including environmentally friendly, biodegradable plastics. In the first step, a slow pyrolysis of polyolefin waste yields oils, containing long-chain olefins as the major components. Then, for the next transformation step, tailored bicyclic (alkyl)(amino)carbene (BICAAC)-Ru olefin metathesis catalysts were used in combination with an alkene isomerization catalyst (RuHCl(CO)(PPh3)3) for the transformation of the pyrolysis oil to propylene via isomerization-metathesis (ISOMET) reaction in ethylene atmosphere. Eventually, translation of the highly efficient single-metal catalyst system enabled ISOMET reaction to a 900 mL reactor setup and repetitive batch experiments could prove the long-term stability of the catalyst system and the highest total turnover number (tTON = 2788 mol propylene per mol olefin metathesis catalyst) reported so far using post-consumer polyethylene waste feedstock. [ABSTRACT FROM AUTHOR]

Bioplastics were produced by mixing starch with sorbitol, glacial acetic acid, and carboxymethyl cellulose (CMC) during the manufacturing process. The physical characteristics of the bioplastics were investigated using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). Tensile strength, elongation, and Young's modulus tests were utilized to assess the mechanical characteristics of bioplastics. The bioplastic with the highest tensile strength was BP3 (7.03 ± 0.34 N/mm2), whereas BP0 had a tensile strength of 1.57 ± 0.11 N/m2. The addition of CMC increased the viscosity of the solution and, consequently, the strength of the bioplastic. The range of bioplastic hydrophobicity was ~ 128.32–323.74%. FTIR and XPS test results indicated that the physical mixing utilized during synthesis did not result in the addition of functional groups other than the native functional groups of the substances since no chemical reaction occurred. The thermal behavior investigation revealed that increasing the amount of CMC added to TPS can increase the presence of O–H functional groups in bioplastics, contributing to an increase in the glass transition temperature. Furthermore, both bioplastics broke down at ~ 250 °C. [ABSTRACT FROM AUTHOR]

The widespread use of traditional petroleum‐based plastics is causing significant environmental pollution for example microplastics issues, due to its non‐biodegradability. Poly (lactic acid) (PLA) as a representative biodegradable polymer is a promising candidate to replace petroleum‐based plastics in some fields of disposable packaging materials and tableware. In this work, in order to improve the poor crystallization, mechanical and heat resistance performances of PLA, styrene–acrylonitrile‐glycidyl methacrylate (SAG) as a chain extender and octamethylenedicarboxylic dibenzoylhydrazide (ST‐NAB3) as a heterogeneous nucleating agent (HNA) were added simultaneously into PLA matrix. The chain‐extended PLA (CPLA) with branch structures had smaller crystal sizes and higher crystal density, compared with those of pure PLA. In addition, thanks to the nucleation effect of ST‐NAB3 and the development of "shish‐kebab", this tendency became more pronounced in CPLA/HNA systems. It was worth mentioning that, CPLA with the ST‐NAB3 content of 1 wt% (CPLA‐1) possessed the highest crystallinity of 43.6%. Meanwhile, CPLA‐1 had the best impact strength and heat deformation temperature of 38.9 kJ/m2 and 91.3°C respectively, which had increased by 11.3 kJ/m2 and 32.4°C contrast to pure PLA. On the whole, this study proposed a simple and effective method, which provided a new possibility for PLA modification research. [ABSTRACT FROM AUTHOR]

Wastewater treatment facilities can filter out some plastics before they reach the open environment, yet microplastics often persist throughout these systems. As they age, microplastics in wastewater may both leach and sorb pollutants and fragment to provide an increased surface area for bacterial attachment and conjugation, possibly impacting antimicrobial resistance (AMR) traits. Despite this, little is known about the effects of persistent plastic pollution on microbial functioning. To address this knowledge gap, we deployed five different artificially weathered plastic types and a glass control into the final maturation pond of a municipal wastewater treatment plant in Ōtautahi-Christchurch, Aotearoa/New Zealand. We sampled the plastic-associated biofilms (plastisphere) at 2, 6, 26, and 52 weeks, along with the ambient pond water, at three different depths (20, 40, and 60 cm from the pond water surface). We investigated the changes in plastisphere microbial diversity and functional potential through metagenomic sequencing. Bacterial 16S ribosomal RNA genes composition did not vary among plastic types and glass controls (P = 0.997) but varied among sampling times [permutational multivariate analysis of variance (PERMANOVA), P = 0.001] and depths (PERMANOVA, P = 0.011). Overall, there was no polymer-substrate specificity evident in the total composition of genes (PERMANOVA, P = 0.67), but sampling time (PERMANOVA, P = 0.002) and depth were significant factors (PERMANOVA, P = 0.001). The plastisphere housed diverse AMR gene families, potentially influenced by biofilm-meditated conjugation. The plastisphere also harbored an increased abundance of genes associated with the biodegradation of nylon, or nylon-associated substances, including nylon oligomer-degrading enzymes and hydrolases. IMPORTANCE Plastic pollution is pervasive and ubiquitous. Occurrences of plastics causing entanglement or ingestion, the leaching of toxic additives and persistent organic pollutants from environmental plastics, and their consequences for marine macrofauna are widely reported. However, little is known about the effects of persistent plastic pollution on microbial functioning. Shotgun metagenomics sequencing provides us with the necessary tools to examine broad-scale community functioning to further investigate how plastics influence microbial communities. This study provides insight into the functional consequence of continued exposure to waste plastic by comparing the prokaryotic functional potential of biofilms on five types of plastic [linear low-density polyethylene (LLDPE), nylon-6, polyethylene terephthalate, polylactic acid, and oxygendegradable LLDPE], glass, and ambient pond water over 12 months and at different depths (20, 40, and 60 cm) within a tertiary maturation pond of a municipal wastewater treatment plant. [ABSTRACT FROM AUTHOR]

Petroleum‐derived plastics are harmful to ecosystems because they are not decomposed in the natural environment. Therefore, the replacement of petroleum‐derived plastics with biodegradable plastics has attracted considerable attention. UV‐barrier films in the agricultural and packaging fields are mainly composed of petroleum‐derived plastics, which have a negative impact on the ecosystem when they leak into the environment. Thermoplastic starch (TPS) is an inexpensive and sustainable biodegradable plastic that has recently attracted considerable attention. In this study, the addition of UV barrier properties and remolding ability to TPS for replacing petroleum‐derived UV barrier films are investigated. Also, a biodegradable polyester coating is studied to improve the water resistance of the prepared UV‐barrier TPS (U‐TPS). To prepare U‐TPS, a conjugated enamine structure is formed by reacting starch acetoacetate with diamine monomers during melt kneading. U‐TPS exhibits high UV barrier properties across the UV regions (200–400 nm) owing to the presence of acetoacetyl groups and enamines. These results indicate the possibility of increasing the utilization of TPS in agriculture and as a packaging material. [ABSTRACT FROM AUTHOR]

The use of fossil-based plastics in food packaging poses a serious environmental concern. Pectin, a natural biodegradable polymer, offers a potential solution for environmentally friendly and sustainable food packaging to replace fossil-based plastics. This article reviews the applications of pectin in active and intelligent packaging and analyzes the latest research trends. Bibliometric analysis was used to review the existing literature on pectin in food packaging. Data were collected from the Scopus database, which covers research on film manufacturing and pectin-based coating. Pectin-based active packaging contains antimicrobial and antioxidant compounds such as ascorbic acid and essential oils, which effectively prevent bacterial growth while absorbing oxygen and water vapor. In contrast, pectin-based intelligent packaging allows real-time monitoring of food quality through integrated color-changing indicators, eliminating the need for open packaging. Research trends have shown a significant increase in publications on pectin-based packaging, reflecting the growing interest in sustainable packaging solutions. With a focus on innovation and sustainability, pectin can replace conventional plastics and provide safer and more durable packaging solutions, thereby supporting global efforts to reduce the environmental impact of plastic waste. [ABSTRACT FROM AUTHOR]

Few studies have investigated the biodegradation of microplastics in marine environments. Microorganisms that can degrade microplastics in high-salinity conditions are sought after. Therefore, we aimed to isolate a halotolerant poly(ε-caprolactone) (PCL)-degrading bacterium for applications in biotechnology. The bacterium isolated from seaside soil was identified as Bacillus gibsonii via phylogenetic analysis based on 16S rRNA gene sequences and designated as KRICT-1. We tested whether the KRICT-1 strain showed halotolerance by determining the sodium chloride (NaCl) tolerance at various concentrations. The KRICT-1 strain showed growth at up to 10% NaCl on Luria–Bertani (LB) medium agar plates and 10% NaCl in liquid LB medium, indicating that KRICT-1 can grow and produce a PCL-depolymerizing enzyme under high-salt conditions. The KRICT-1 strain could depolymerize PCL with a PCL film weight loss of 2.82% at up to 10% NaCl concentration after cultivation of 7 weeks. KRICT-1 is the first strain of B. gibsonii which shows PCL-depolymerizing activity. Scanning electron microscopy and water contact angle results confirmed the degradation of PCL by the KRICT-1 strain. The extracellular enzyme produced by the KRICT-1 strain was stable over a wide range of temperatures (15–40 °C) and pH (7.0–9.5). This halotolerant PCL-degrading bacterium can be used in the degradation of biodegradable plastics present in saline soils, saline water, and wastewater. [ABSTRACT FROM AUTHOR]

The increase in the use of plastics during the past few decades has caused environmental pollution due to the non-biodegradable and recalcitrance nature of the plastics. This has caused great problems for the solid waste management efforts. The development of biodegradable polymers from natural and renewable ingredients can address the challenges caused by plastic pollution. The present work deals with the optimization of the preparation process of sago starch-based biodegradable bioplastic films. The sago starch, glycerol-sorbitol mixture, and chitosan were used as polysaccharides, plasticizers, and antimicrobial agents, respectively. The factors screening and design optimization were performed using response surface methodology and Box-Behnken Design to investigate the interactions between all components in the film preparation. Furthermore, the developed bioplastic films were characterized through field emission scanning electron microscopy and Fourier transform infrared spectroscopy. The antimicrobial susceptibility assay showed the inhibition of the growth of Bacillus pumilus and Alcaligenes faecalis XF1 by incorporation of cinnamon essential oil into the film. Moreover, the developed films successfully reduced the proliferation of fungal growth on packaged bread samples. The microbial analysis found that the shelf life of the wheat bread was improved from 3 to 15 days. The sago starch bioplastic films developed in this study can potentially meet the requirements for food packaging films. [ABSTRACT FROM AUTHOR]

Poly(butylene adipate-co-terephthalate) (PBAT), a widely studied biodegradable material, has not effectively addressed the problem of plastic waste. Taking into consideration the cost-effectiveness, upcycling PBAT should take precedence over direct composting degradation. The present work adopts a chain breaking-crosslinking strategy, upcycling PBAT into dual covalent adaptable networks (CANs). During the chain-breaking stage, the ammonolysis between PBAT and polyethyleneimine (PEI) established the primary crosslinked network. Subsequently, styrene maleic anhydride copolymer (SMA) reacted with the hydroxyl group, culminating in the formation of dual covalent adaptable networks. In contrast to PBAT, the PBAT-dual-CANs exhibited a notable Young's modulus of 239 MPa, alongside an inherent resistance to creep and solvents. Owing to catalysis from neighboring carboxyl group and excess hydroxyl groups, the PBAT-dual-CANs exhibited fast stress relaxation. Additionally, they could be recycled through extrusion and hot-press reprocessing, while retaining their biodegradability. This straightforward strategy offers a solution for dealing with plastic waste. [ABSTRACT FROM AUTHOR]

Biodegradable plastics applied to soil stimulate the production of greenhouse gases and inhibit plant growth under aerobic conditions. This study aimed to examine the effects of biodegradable plastics on paddy rice growth and greenhouse gas emission under flooding conditions in pot experiments and also on greenhouse gas production under flooding conditions in an incubation experiment. Two series of pot experiments were conducted with rice (Oryza sativa). First series as immediate flooded and 2nd series as 2 weeks nonflooding before flooded, and both kept flooded until harvest. The following four kinds of materials were added to the sandy paddy soil, (1) nonwoven fabric sheets made of polylactic acid and polybutylene-succinate, (2) laminate sheets made of polybutylene adipate terephthalate and pulp, (3) cellulose filter paper, and (4) rice straw. Only soil was used as control. Methane (CH4) emission, measured by chamber method followed by gas chromatography, was significantly larger only in the cellulose treatment than the laminate treatment in the immediate flooded series, indicating that biodegradable plastics had no significant impact on CH4 emission from paddy rice soil. Rice growth and yield did not show significant difference among treatments in both series. Incubation experiment showed the largest CH4 production in cellulose-amended soil, followed by straw-amended and laminate amended soils, and least in fabric-amended soil, while CO2 did not show significant differences among treatments. We need further examination with different biodegradable plastics for a longer period that test used in this study. [ABSTRACT FROM AUTHOR]

Biopolymer materials have attracted attention due to their richness, sustainability, environmental friendliness, and biodegradability properties. This review explores recent advances in biopolymer synthesis, properties, and their commercial applications. Biopolymers, derived from renewable sources, have garnered significant attention due to their environmental benefits and potential to replace conventional petrochemical-based plastics. The synthesis of biopolymer delves into innovative biopolymer production techniques, including microbial fermentation, chemical modifications, and novel biotechnological approaches. A detailed examination of the unique properties of biopolymers, including physical, thermal, mechanical, and optical characteristics of naturally generated biopolymers. It explores the diverse range of applications of biopolymers across industries, including packaging for the food industry, biomedical engineering, cosmetics, and different mechanical applications. The review further discusses the growing commercial applications of biopolymers across various industries, such as packaging, agriculture, medicine, and textiles. This review aims to provide an understanding of the current method of synthesis properties and future potential application of biopolymers in advancing sustainable materials science. [Display omitted] • The biopolymeric materials synthesis techniques are discussed. • Potential of biomass wastes towards the extraction of biopolymer is explored. • Biopolymeric material properties and applications are summarized. • Recent development of biopolymer for different application are discussed [ABSTRACT FROM AUTHOR]

Enzymatic degradation of poly(ethylene terephthalate) (PET) into its corresponding monomers provides an attractive route for green plastic recycling and environmental remediation applications. However, the binding of PET hydrolases toward the PET surface is a rate-limiting step in PET degradation. Hence, we selected three anchor peptides and four linker peptides to fuse the previously engineered leaf-branch compost cutinase for facilitating enzyme binding and improving degradation of real post-consumer PET wastes of Coca Cola and C′eastbon PET bottles, with using the amorphous PET as a control. The systematical characterization of the seven cutinases revealed that the anchor peptide with moderate hydrophobicity plus chaperone activity and the flexible linker peptide with small hydrophobicity but long length were more suitable for each domain to serve its own role, affording the facilitated PET binding affinities and enhanced PET degradation performance. Thus, the optimal fusion cutinase possessed up to 3.3 times higher catalytic efficiency (k cat / K m) and 76 % increased long-term degradation performance than the parental cutinase, respectively. Further, complete degradation of C′eastbon PET wastes and 77 % degradation of Coca Cola PET wastes were achieved by the optimal cutinase of 33.3 nmol·g−1 PET in 96 h, proving its superiority against the real post-consumer PET wastes. [Display omitted] • Varying anchor and linker peptides were fused to an engineered variant of cutinase. • Real polyethylene terephthalate (PET) wastes were degraded by seven cutinases. • Effects of anchor and linker peptides on enzymatical PET degradation were explored. • Catalytic efficiency was enhanced 3.3 times by the optimal fusion strategy. • Optimal cutinase of 33.3 nmol·g−1 PET completely degraded C′eastbon PET wastes in 96 h. [ABSTRACT FROM AUTHOR]

Bioplastics such as polylactic acid are actually promoted as eco-friendly alternatives to fossil fuel-derived plastics, yet bioplastic toxicity remains poorly known. Here we studied the acute and multigenerational effects of polylactic acid microplastics on the copepod Eurytemora affinis, a bioindicator species of zooplankton. Results on acute toxicity revealed that lethal concentration values are higher for adult males, of 134.6 mg microplastic/L, than for adult females, of 106.9 mg/L. In multigeneration exposure, 400 µg/L polylactic acid microplastics induced higher mortality, production of smaller-sized eggs, elongation of the naupliar phase, and offspring with lower fitness. This led to reduction in female body size, including prosome length, width, and volume. Noteworthy, we also observed a recovery in copepod survival and reproductive parameters in the fifth filial generation. [ABSTRACT FROM AUTHOR]

Fossil fuel-based products should be replaced by products derived from modern biomass such as plant starch, in the context of the future circular economy. Starch production globally surpasses 50 million tons annually, predominantly sourced from maize, rice, and potatoes. Here, we review plant starch with an emphasis on structure and properties, extraction, modification, and green applications. Modification techniques comprise physical, enzymatic, and genetic methods. Applications include stabilization of food, replacement of meat, three-dimensional food printing, prebiotics, encapsulation, bioplastics, edible films, textiles, and wood adhesives. Starch from maize, potatoes, and cassava shows amylose content ranging from 20 to 30% in regular varieties to 70% in high-amylose varieties. Extraction by traditional wet milling achieves starch purity up to 99.5%, while enzymatic methods maintain higher structural integrity, which is crucial for pharmaceutical applications. Enzymatic extraction improves starch yield by of up to 20%, reduces energy consumption by about 30%, and lowers wastewater production by up to 50%, compared to conventional methods. Sustainable starch modification can reduce the carbon footprint of starch production by up to 40%. Modified starches contribute to approximately 70% of the food texturizers market. The market of starch in plant-based meat alternatives has grown by over 30% in the past five years. Similarly, the use of biodegradable starch-based plastics by the bioplastic industry is growing over 20% annually, driven by the demand for sustainable packaging.Kindly check and confirm the layout of Table 1.Layout is right [ABSTRACT FROM AUTHOR]

Sustainable food packaging materials have significant interest in addressing environmental issues by making renewable substitutes such as bioplastics based on pectin. Orange peel has a relatively high pectin content of 42.5%, which can be synthesized into bioplastics. Pectin-based bioplastics tend to have limitations in terms of mechanical and physical strength due to the hygroscopic nature of pectin. This study aims to determine the effect of adding glycerol and sago starch on the characteristics of orange peel pectinbased bioplastics. The casting method was used in the bioplastic formulation using the variation of the pectin:starch ratio (75:25, 65:35, 55:45; and 50:50%) and glycerol composition (10, 20, 30, and 40%). Based on the results, the pectin obtained was categorized as low methoxyl pectin and ester pectin. The characterizations of bioplastics achieved the maximum value of the tensile strength of bioplastics was 4.22 MPa, obtained by adding pectin:starch (50:50%) and 10% glycerol. The maximum value of the elongation properties at the break of bioplastics is 24%, obtained by adding the composition of pectin:starch (75:25%) and 40% glycerol. The more additions of the pectin:starch and glycerol composition result in a higher water vapor evaporation rate. Hence, utilizing orange peel pectin-based bioplastics offers a sustainable solution by exploring repurposing waste to create bioplastics for food packaging, thereby contributing to environmental preservation. [ABSTRACT FROM AUTHOR]

Synthetic plastics are in great demand in society due to their diversified properties, but they cause environmental pollution due to their non-biodegradable nature. Therefore, synthetic plastics are in need to be replaced with biodegradable plastics. Polyhydroxyalkanoates (PHAs), bacterial biopolymers are natural alternative to synthetic plastics. These are present inside the bacterial cytoplasm in granular form. Presently, the production cost of PHA is high due to expensive carbon substrates used in its biosynthesis. Therefore, this study focuses on the cost-effective production of PHA using waste carbon sources. Rice bran and sugarcane molasses were used as the carbon source for PHA production from Bacillus subtilis, Bacillus cereus, Alcaligenes sp. and Pseudomonas aeruginosa. PHA production from these bacterial strains was confirmed through Sudan Black-B screening. With rice bran, as carbon source, the highest PHA yield obtained was for P. aeruginosa, which yielded 93.7% and lowest was 35.5% for B. cereus. Surprisingly, B. cereus produced the highest cell dry mass (0.045 g/L) but its extracted PHA contents were lowest being only 0.02 g/L. Alcaligenes sp. with 0.031 g/L CDM yielded 87.1% PHA. B. subtilis had a CDM 0.029 g/L, 0.02 g/L PHA content and a yield of 69.10%. In the case of sugarcane molasses, P. aeruginosa produced 95% PHA yield, 0.02 g/L CDM, and 0.019 g/L PHA content. Alcaligenes sp. yielded 90.9% PHA, 0.011 g/L CDM, and 0.01 g/L PHA content. B. subtilis produced 91.6% PHA yield, 0.012 g/L CDM, 0.011 g/L PHA content; B. cereus produced 80% PHA yield, 0.015 g/L CDM, 0.012 g/L PHA content at 37 °C, pH 7. Higher concentrations of carbon sources increased the CDM and decreased the PHA yield. The maximum yield of PHA was obtained from sugarcane molasses. 24–48 h of incubation was optimal for B. subtilis and B. cereus, while for Alcaligenes and P. aeruginosa incubation time of 48–96 h was desirable for higher PHA yield. The extracted biopolymers were analyzed by Fourier transform infrared spectroscopy (FTIR), which identified the extracted biopolymers as poly-3-hydroxybutyrate P(3HB). The thermal properties of the extracted biopolymers, such as melting temperatures, were analyzed by differential scanning calorimetry (DSC), which confirmed the thermal stability. [ABSTRACT FROM AUTHOR]

Bio-derived materials could play a major role in future supportable green and health technologies. Nontraditional materials such as proteins and biopolymers are observed for their probable use in the fabrication of bioplastics for packaging. In the present work, novel ternary composite films of chitosan (CS), polyvinyl alcohol (PVA), with different ratios of natural egg white (EW) and glycerol as a plasticizer, were fabricated by solution casting technique. The synthesized ternary composite films were characterized by UV–Vis absorption spectra, Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analysis. The hydrophobicity of as-synthesized samples was confirmed by contact angle measurement. The microbiological screening analysis was established against bacteria viz. Pseudomonas sp., Bacillus subtilis and Staphylococcus aureus bacteria. The attained results denoted that the film might be an appropriate applicant for food packaging applications. [ABSTRACT FROM AUTHOR]

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Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Over the past few decades, synthetic petroleum-based packaging materials have increased, and the production of plastics has surpassed all other man-made materials due to their versatility. However, the excessive usage of synthetic packaging materials has led to severe environmental and health-related issues due to their nonbiodegradability and their accumulation in the environment. Therefore, bio-based packages are considered alternatives to substitute synthetic petroleum-based packaging material. Furthermore, the choice of packing material in the food industry is a perplexing process as it depends on various factors, such as the type of food product, its sustainability, and environmental conditions. Interestingly, due to proven mechanical, gas, and water vapor barrier properties and biological activity, polysaccharide-based bioplastics show the potential to expand the trends in food packaging, including edible films or coatings and intelligent and active food packaging. Various chemical modifications, network designs, and processing techniques have transformed polysaccharide materials into valuable final products, particularly for large-scale or high-value applications. Transitioning from petroleum-based resources to abundant bio-based polysaccharides presents an opportunity to create a sustainable circular economy. The economic viability of polysaccharide-based bioplastics is determined by several factors, including raw material costs, production technologies, market demand, and scalability. Despite their potential advantages over traditional plastics, their economic feasibility is affected by continuous technological advancements and evolving market dynamics and regulations. This review discusses the structure, properties, and recent developments in polysaccharide-based bioplastics as green and sustainable food packaging materials. [ABSTRACT FROM AUTHOR]

The study investigates the properties and waste management potential of cellulose acetate waste, commonly used in cigarette filter production. The goal of the research is to address gaps in the state of the art by assessing compostability and phytotoxicity of acetate waste from cigarettes production, which significantly complement the current research focused on cigarette filters in the form of post-consumer buts. Under investigation was acetate in the form of homogenic, dye-free and non-contaminated tow from the beginning phase of the cigarette's filters production process. The experimental framework adheres to the PN-EN 14045:2005 standard for controlled composting environments. Acute phytotoxicity assessment follows the PHYTOTESTKIT method based on PN-EN 11269-1:2013-06. Results indicate that under controlled conditions, acetate waste achieves a decomposition rate of 75.3% after 84 days. Phytotoxicity testing reveals varying germination rates for different plant species. Across substrates, only 81 out of 210 seeds germinated (39%). Specifically, green cucumber seeds showed no germination, oat seeds had a 29% germination rate (20% for compost with acetate), and cress seeds had a high 90% germination rate for each substrate. Overall, understanding these properties informs sustainable waste management practices, including potential applications in industries like geotextiles, crop mulching mats etc. The results led to the conclusion that additional testing should be perform according to the requirements specific for each industrial usage and to increase the compostability level under laboratory and natural conditions. [ABSTRACT FROM AUTHOR]