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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.

Microbial fermentation has provided fermented foods and important chemicals such as antibiotics, amino acids, and vitamins. Metabolic engineering of synthetic microbes has expanded the range of compounds produced by fermentation. Petroleum-derived aromatic compounds are widely used in industry as raw materials for pharmaceuticals, dyes, and polymers and are in great demand. This review highlights the current efforts in the microbial production of various aromatic chemicals such as aromatic amines, cinnamic acid derivatives, and flavoring aromatics, including their biosynthesis pathways. In addition, the unique biosynthetic mechanism of pyrazine, a heterocyclic compound, from amino acids is described to expand the use of biomass-derived aromatic compounds. I also discuss our efforts to develop high-performance bioplastics superior to petroleum plastics from the aromatic compounds produced by microbial fermentation. [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]

Cassava pulp (CP) generated annually in Thailand has become the major agro-industrial solid waste problem, but its potential for volatile fatty acids (VFAs) production has not been intensively explored. Waste-derived VFAs gained attention due to their broad applications as substrates for biomethane and bioplastic or bio-based chemicals, replacing petrochemical-based ones. This study proposed the next generation of CP waste management for VFAs production as renewable and inexpensive substrates for biogas and bioplastic prospects. A microbial consortium enriched with hydrolytic and acidogenic bacteria (EHA) was used as inoculum seed for anaerobic fermentation of CP to produce VFAs. The stepwise increasing substrate to 5% CP resulted in VFAs yield of up to 0.16 g acetic acid and 0.22 g butyric acids per g of CP added, requiring only 1% of microbial inoculum. Acid-tolerant spore-forming Clostridium dominated the EHA consortium and was easy to maintain during stress conditions. If the annual CP generated is subjected to this proposed waste management system, 0.31 million tons of acetic acid and 0.43 million tons of butyric acid can be produced annually. These VFAs can be further used as mixed VFAs for biomethane and bioplastic production prospects or extracted as a pure VFA and sold to the chemicals market. Moreover, bio-transformation of CP into VFAs through fermentation using the special EHA consortium requires minimum operational cost and produces high-economy products while minimizing greenhouse gas emissions to the atmosphere. This next-generation CP waste utilization will be of good use in the future by contributing to sustainable development goals. [ABSTRACT FROM AUTHOR]

Bioplastic is a biodegradable and environmentally friendly material because it uses natural materials in the form of plant fibers. The plants with high fiber content can be converted to cellulose acetate as a raw material for bioplastics. Durian skin is a biomass waste that has the potential to be a raw material for bioplastics. Cellulosebased bioplastics are generally made by adding adhesives, plasticizers, and fillers. In this study, the manufacture of bioplastics used the cellulose acetate from durian skin with variations of plasticizer concentration, plasticizer type, starch adhesive, and chitosan. Glycerol and sorbitol were used as plasticizers with variations in concentration of 20%, 30%, and 40%. The mass ratio of cellulose and starch used was 1.5:1. Bioplastics were produced by adding chitosan, starch, and variations of plasticizers in each concentration which were achieved varying values in tensile strength, water absorption, density values, elongation values, Young's modulus, degradability, and different bioplastic surface structures. The best bioplastic result is bioplastic with 20% sorbitol concentration for a density of 0.852 g/mL, water absorption of 45.99%, tensile strength of 613.12 Kpa, elongation of 2.35%, and Young's modulus of 26090.21 Kpa. In addition, the degradation time without landfill has met the Indonesian National Standard (INS) for 45 days. [ABSTRACT FROM AUTHOR]

Biodegradable bioplastics are becoming the best solution ever to combat the environmental pollution caused by petroleum-based synthetic plastics. In this study, potato peel starch (PPS)–based bioplastic film was developed by a method of gelatin casting, in which the effect of 13.33, 23.33, and 33.33% v/w (HCl or glycerol to PPS ratio) concentration of HCl and glycerol as well as drying temperature (45 °C, 55 °C, and 65 °C) was studied. The experiment was designed and optimized by a three-variable, three-level Box-Behnken design using Response Surface Methodology (Design Expert® software version 13.0.1). The ANOVA analysis showed that the model was significant with p < 0.0001. The optimum values of the influencing factors were found to be HCl concentration 23.33%v/w, glycerol 20%v/w, and 48 °C drying temperature. The FTIR results confirmed that the compatibility between false banana (Ensete ventricosum) fiber and PPS was attributed to the intermolecular hydrogen bonding and uniform dispersion of fiber during the blending and film formation. The micrograph for pure bioplastic film showed uniform and dense matrix except the irregular dimpled surface formed during the gelatinization process. Peaks were demonstrated at 2θ values of 15.19°, 17.31°, 22.96°, and 24.1° by PPS in the XRD spectrum. Under optimal conditions, a bioplastic film with tensile strength of 6.449 MPa, percent elongation at break of 19.87%, biodegradability of 83.92%, and water absorption of 59.94% was synthesized in this study. Biodegradability studies on the PPS-based bioplastic synthesized by the plasticization of glycerol and sorbitol have shown a biodegradation % of 81.42 and 70.25 in moist soil, respectively. The produced bioplastic film had sufficient physicochemical properties confirming the usage of waste potato peel as a source of starch for the synthesis of biodegradable bioplastics that can substitute conventional plastics. [ABSTRACT FROM AUTHOR]

With the growing population and the drastic depletion of fossil fuels, the demand for the bioproduction of value-added products is increasing. Recently, lactic acid in polylactic acid (PLA) has been extensively explored for bioplastic applications and other traditional applications in the food industry, textile industry, and pharmaceutical industry. The limitation of large-scale production and application of PLA in bioplastic production hinders the economic production, which challenges downstream techniques for lactic acid purification. Valorizing waste biomass such as food waste, lignocellulosic biomass, dairy industry, and fruit and vegetable processing for cheap carbon sources will support the reduction of the production cost of lactic acid. Metabolic engineering approaches have been extensively studied, such as the overexpression of lactic acid genes from traditional producers and monocarboxylate transporter genes in microbial cell factories. Through this, the movement of lactate molecules across the membrane is improved, and various studies have reported the enhanced production of lactic acid. The purification of lactic acid has also been studied for a long time using various techniques such as precipitation, adsorption, esterification, liquid–liquid extraction, and membrane-based techniques. A detailed review of lactic acid purification techniques with a small emphasis on aqueous two-phase system methods is discussed in the paper. [ABSTRACT FROM AUTHOR]

This study focuses on creating a biodegradable film composed of chitosan, Indian Gooseberry (IG) extract, and silver nanoparticles (AgNPs), designed to enhance antimicrobial properties and improve food preservation. The presence of AgNPs and IG extract not only dramatically exhibits 99% efficiency in the antimicrobial activity against Staphylococcus aureus (ATCC 6538P), but also achieves this within a remarkably short time interval of ≈20 min. This potent antimicrobial action is attributed to the synergistic effect between the bioactive compounds in the IG extract and the nanoscale silver particles, which together create a highly hostile environment for microbial growth. Moreover, this synergy contributes to 313.94% water vapor transmittance rate and the complete biodegradability of the composite film (93.42% at the end of the second month), ensuring that it leaves no harmful residues in the environment post‐use. The reinforced film exhibits improved hydrophobicity (55.43%), which is crucial for protecting food products from moisture and extending their shelf life. Specifically, the film has been tested as a packaging material for bread, showing a significant extension in shelf life by effectively preventing mold growth and retaining freshness for an extended period (14 days). [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]

Water-repellent coatings are essential for enhancing the durability and sustainability of textiles, paper, and bioplastic polymers. Despite the growing use of sustainable materials, their inherent hydrophilicity presents significant challenges. This review explores advanced coating technologies to address these issues, focusing on their mechanisms, properties, and applications. By imparting water resistance and repellency, these coatings improve material performance and longevity. The environmental impact and limitations of current coatings are critically assessed, highlighting the need for sustainable solutions. This review identifies key trends and challenges, offering insights into developing water-resistant materials that align with environmental goals while meeting industry demands. Key focus areas include coating mechanisms, techniques, performance evaluation, applications, environmental impact assessment, and the development of sustainable coating solutions. This research contributes to the development of water-resistant materials that meet the demands of modern industries while minimizing environmental impact. [ABSTRACT FROM AUTHOR]

This article provides information on the synthesis and properties of polylactic acid (PLA), a biodegradable plastic made from renewable resources. It discusses the use of tin(II) chloride for PLA synthesis and the addition of additives to alter its properties. The article also explores the environmental impact and sustainability of bioplastics, highlighting the need for comprehensive life cycle assessments and improved recycling infrastructure. It suggests that a focus on energy aspects and global recycling may be more promising than solely relying on bioplastics. [Extracted from the article]

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]

The serious environmental threat caused by petroleum-based plastics has spurred more researches in developing substitutes from renewable sources. Starch is desirable for fabricating bioplastic due to its abundance and renewable nature. However, limitations such as brittleness, hydrophilicity, and thermal properties restrict its widespread application. To overcome these issues, covalent adaptable network was constructed to fabricate a fully bio-based starch plastic with multiple advantages via Schiff base reactions. This strategy endowed starch plastic with excellent thermal processability, as evidenced by a low glass transition temperature (Tg = 20.15 °C). Through introducing Priamine with long carbon chains, the starch plastic demonstrated superior flexibility (elongation at break = 45.2%) and waterproof capability (water contact angle = 109.2°). Besides, it possessed a good thermal stability and self-adaptability, as well as solvent resistance and chemical degradability. This work provides a promising method to fabricate fully bio-based plastics as alternative to petroleum-based plastics. [ABSTRACT FROM AUTHOR]

Plastic food packaging causes massive pollution in the environment via resource extraction, gas emissions, and the enduring plastic waste accumulation. Hence, it is of crucial importance to discover sustainable alternatives in order to protect ecosystems and conserve precious resources. Recently, seaweed has been emerging as a promising sustainable solution to plastic pollution. Seaweed is a fast-growing marine plant that is abundant in tropical coastlines and requires minimal resources to cultivate. In addition, seaweed is rich in valuable polysaccharides such as alginate, fucoidan, carrageenan, agar, and ulva, which can be extracted and processed into biodegradable films, coatings, and wraps. This ability allows the creation of an alternative to plastic food packages that are completely biodegradable, made from renewable resources, and do not linger in landfills or oceans for centuries. In this context, this review discusses the main classification of seaweed, their production and abundance in the world, and provides a summary of seaweed-based materials developed in the last 2–5 years for potential usage in the food packaging sector. [ABSTRACT FROM AUTHOR]

Tremendously negative effects have been generated in recent decades by the continuously increasing production of conventional plastics and the inadequate management of their waste products. This demands the production of materials within a circular economy, easy to recycle and to biodegrade, minimizing the environmental impact and increasing cost competitiveness. Bioplastics represent a sustainable alternative in this scenario. However, the replacement of plastics must be addressed considering several aspects along their lifecycle, from bioplastic processing to the final application of the product. In this review, the effects of using different additives, biomass sources, and processing techniques on the mechanical and thermal behavior, as well as on the biodegradability, of bioplastics is discussed. The importance of using bioplasticizers is highlighted, besides studying the role of surfactants, compatibilizers, cross-linkers, coupling agents, and chain extenders. Cellulose, lignin, starch, chitosan, and composites are analyzed as part of the non-synthetic bioplastics considered. Throughout the study, the emphasis is on the use of well-established manufacturing processes, such as extrusion, injection, compression, or blow molding, since these are the ones that satisfy the quality, productivity, and cost requirements for large-scale industrial production. Particular attention is also given to fused deposition modeling, since this additive manufacturing technique is nowadays not only used for making prototypes, but it is being integrated into the development of parts for a wide variety of biomedical and industrial applications. Finally, recyclability and the commercial requirements for bioplastics are discussed, and some future perspectives and challenges for the development of bio-based plastics are discussed, with the conclusion that technological innovations, economic incentives, and policy changes could be coupled with individually driven solutions to mitigate the negative environmental impacts associated with conventional plastics. [ABSTRACT FROM AUTHOR]

Abstract\nThis visual research essay considers how a collaborative art practice using bioplastic might enable transformative ecopedagogies. Drawing on a call-and-response method that is steeped in a unique combination of African and Western materialist perspectives, the collaborators think with, call on, and respond to bioplastic agency through conversations, provocations, learnings, and artmaking. Illustrating our experimental Padlet play, our visual research essay explores how a call-and-response bioplastic investigation might enliven inter/intra-actions between materials, minds, bodies, and documents, and in so doing, offer a means of engendering ecological awareness through and across realities and distance. The essay also contributes to debates about notions of ecopedagogical inquiry by inviting readers to engage with the text, images, provocations and process in multiple ways, beyond what is possible within written accounts of research and pedagogy alone.Read the transcriptWatch the video on Vimeo© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group [ABSTRACT FROM AUTHOR]

Plastic is a material that is often used as a storage medium, equipment and also furniture to support human activities, but plastic is not easily broken down by the environment. Bioplastic technology is one of the efforts made to address the problem of plastic packaging which can pollute the environment. Environmentally friendly plates, bioplastic products made from tapioca, glycerol and sugar cane bagasse. This research aims to determine the effect of variations in the size of bagasse on tensile strength, elongation at break, water resistance and biodegradability of environmentally friendly plates and to obtain the best formulation of varying sizes of bagasse as raw material for making environmentally friendly plates. This research used a Completely Randomized Design (CRD) with one factor, namely variation in the size of the bagasse. The results of this research show that there is a real influence between tensile strength, water resistance and biodegradability, however, in the elongation test, variations in bagasse did not have a significant effect. Tensile strength values range from 20.00 N/mm2 to 47.72 N/mm2. The largest elongation value is 4.08%. The highest water resistance is at room temperature, namely 88.86% with a degree of curvature of 16° and in water with a temperature of 60°C, namely 85.02% with a degree of curvature of 18.75°. Variations in the size of bagasse also affect the biodegradability of environmentally friendly plates which ranges from 11.77% to 14.65%. The best treatment is a sample with a variety of bagasse sizes of 60 mesh, because it has high strength compared to other samples. [ABSTRACT FROM AUTHOR]

The valorisation of food by-products is an important step towards sustainability in food production. Tomatoes constitute one of the most processed crops in the world (160 million tonnes of tomatoes are processed every year), of which 4% is waste. This translates to 6.4 million tonnes of tomato skins and seeds. Currently, this waste is composted or is used in the production of low-value animal feed; higher value can be achieved if this waste stream is re-appropriated for more advanced purposes. Plant cuticle is a membrane structure found on leaves and fruit, including tomatoes, and is mainly composed of cutin. The main function of plant cuticle is to limit water loss from the internal tissue of the plant. Cutin, which can be recovered from the tomato skins by pH shift extraction, has hydrophobic (water repellent) properties and is therefore an ideal raw material for the development of a novel water-resistant coating. In this study, biomass-based bioplastics were developed. Unfortunately, although these bioplastics have good mechanical properties, their hydrophilic nature results in poor water barrier properties. To mitigate this, a very effective water-resistant coating was formulated using the cutin extracted from tomato peels. The water vapour permeability rates of the bioplastics improved by 74% and the percentage swelling of the bioplastic improved by 84% when treated with the cutin coating. With physicochemical properties that can compete with petroleum-based plastics, these bioplastics have the potential to address the growing market demand for sustainable alternatives for food packaging. Using ingredients generated from by-products of the food processing industries (circular economy), the development of these bioplastics also addresses the UN's Sustainable Development Goal (SDG) 12, Sustainable Consumption and Production (SCP). [ABSTRACT FROM AUTHOR]

Bioplastics are emerging as a promising alternative to traditional plastics, driven by the need for more sustainable options. This review article offers an in-depth analysis of the entire life cycle of bioplastics, from raw material cultivation to manufacturing and disposal, with a focus on environmental impacts at each stage. It emphasizes the significance of adopting sustainable agricultural practices and selecting appropriate feedstock to improve environmental outcomes. The review highlights the detrimental effects of unsustainable farming methods, such as pesticide use and deforestation, which can lead to soil erosion, water pollution, habitat destruction, and increased greenhouse gas emissions. To address these challenges, the article advocates for the use of efficient extraction techniques and renewable energy sources, prioritizing environmental considerations throughout the production process. Furthermore, the methods for reducing energy consumption, water usage, and chemical inputs during manufacturing by implementing eco-friendly technologies. It stresses the importance of developing robust disposal systems for biodegradable materials and supports recycling initiatives to minimize the need for new resources. The holistic approach to sustainability, including responsible feedstock cultivation, efficient production practices, and effective end-of-life management. It underscores the need to evaluate the potential of bioplastics to reduce plastic pollution, considering technological advancements, infrastructure development, and increased consumer awareness. Future research should focus on enhancing production sustainability, understanding long-term ecological impacts, and advancing bioplastics technology for better performance and environmental compatibility. This comprehensive analysis of bioplastics' ecological footprint highlights the urgent need for sustainable solutions in plastic production. [ABSTRACT FROM AUTHOR]

Anaerobic digestion under hydrogen (H2)/carbon dioxide (CO2)-versus nitrogen (N2)-purged conditions was examined for the potential for biogas enhancement in the presence of polylactic acid. With or without polylactic acid, H2/CO2 purging demonstrated a 25% higher methane (CH4) production, reaching approximately 160 NmL CH4/g VSadd compared to N2 purging. When H2/CO2 was purged with polylactic acid, there was reduced dominance of Spirochaetales, resulting in fewer intermediates that caused a similar amount of CH4 yield. Despite similar CH4 yield to conditions without polylactic acid, verification through Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) confirmed extensive polylactic acid decomposition. DSC revealed double melting peaks at 151.8 °C and 156.1 °C, indicating increased crystallinity and vigorous polylactic acid decomposition, particularly in the amorphous region, under H2/CO2 purging. This aligned with the decrease in the FTIR carbonyl index, visually confirmed using SEM. Metagenome sequencing highlighted the prevalence of hydrogenotrophic methanogens, Anaerolineales, Bacteroidales, and Thermoanaerobacterales under H2/CO2 purging, demonstrating higher polylactic acid degradation compared to N2 purging conditions. This study revealed a potential for biogas upgrading with waste management of polylactic acid. [ABSTRACT FROM AUTHOR]

Abstract 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.

Plastics derived from fossil fuels are an important part of modern life and it is the most commonly used material in every industrial sector. The use of plastics is increasing day by day and its degradation has become a great challenge. Moreover, non-degradable plastic polymers tend to accumulate as waste in the environment posing a major ecological threat and climate change issues. Therefore, the identification of microbes that can grow easily on plastic and the novel biological agents with exert degradative potential on plastic material have been reviewd herein. In light of these, the enzymatic process can lead to the conversion of plastic into water, carbon dioxide, and methane as a byproduct. Furthermore, fossil fuels utilized to make plastic items are going to be shortened, therefore scientists are finding novel biobased alternatives. In this regard, starch can be promising biopolymer for bioplastic synthesis after understanding underlysing the biological deterioration process and biotic as well as abiotic mechanisms. Hence, this review specifically presents an extensive evaluation of bioplastic from animal waste that can bring revolutionary changes in the environment to mitigate the climate changes.

The valorisation of food by-products is an important step towards sustainability in food production. Tomatoes constitute one of the most processed crops in the world (160 million tonnes of tomatoes are processed every year), of which 4% is waste. This translates to 6.4 million tonnes of tomato skins and seeds. Currently, this waste is composted or is used in the production of low-value animal feed; higher value can be achieved if this waste stream is re-appropriated for more advanced purposes. Plant cuticle is a membrane structure found on leaves and fruit, including tomatoes, and is mainly composed of cutin. The main function of plant cuticle is to limit water loss from the internal tissue of the plant. Cutin, which can be recovered from the tomato skins by pH shift extraction, has hydrophobic (water repellent) properties and is therefore an ideal raw material for the development of a novel water-resistant coating. In this study, biomass-based bioplastics were developed. Unfortunately, although these bioplastics have good mechanical properties, their hydrophilic nature results in poor water barrier properties. To mitigate this, a very effective water-resistant coating was formulated using the cutin extracted from tomato peels. The water vapour permeability rates of the bioplastics improved by 74% and the percentage swelling of the bioplastic improved by 84% when treated with the cutin coating. With physicochemical properties that can compete with petroleum-based plastics, these bioplastics have the potential to address the growing market demand for sustainable alternatives for food packaging. Using ingredients generated from by-products of the food processing industries (circular economy), the development of these bioplastics also addresses the UN’s Sustainable Development Goal (SDG) 12, Sustainable Consumption and Production (SCP).

Abstract Background Plastic is widely utilized in packaging, frameworks, and as coverings material. Its overconsumption and slow degradation, pose threats to ecosystems due to its toxic effects. While polyhydroxyalkanoates (PHA) offer a sustainable alternative to petroleum-based plastics, their production costs present significant obstacles to global adoption. On the other side, a multitude of household and industrial activities generate substantial volumes of wastewater containing both organic and inorganic contaminants. This not only poses a threat to ecosystems but also presents opportunities to get benefits from the circular economy. Main body of abstract Production of bioplastics may be improved by using the nutrients and minerals in wastewater as a feedstock for microbial fermentation. Strategies like feast-famine culture, mixed-consortia culture, and integrated processes have been developed for PHA production from highly polluted wastewater with high organic loads. Various process parameters like organic loading rate, organic content (volatile fatty acids), dissolved oxygen, operating pH, and temperature also have critical roles in PHA accumulation in microbial biomass. Research advances are also going on in downstream and recovery of PHA utilizing a combination of physical and chemical (halogenated solvents, surfactants, green solvents) methods. This review highlights recent developments in upcycling wastewater resources into PHA, encompassing various production strategies, downstream processing methodologies, and techno-economic analyses. Short conclusion Organic carbon and nitrogen present in wastewater offer a promising, cost-effective source for producing bioplastic. Previous attempts have focused on enhancing productivity through optimizing culture systems and growth conditions. However, despite technological progress, significant challenges persist, such as low productivity, intricate downstream processing, scalability issues, and the properties of resulting PHA. Graphical abstract

Abstract Background Plastic is generating global pollution and the replacement such as bioplastic has been developed to mitigate the pollution. To this end, the fate, transformation and pathway of bioplastics need more research. For example, the fragmentation of bioplastic can release small debris that can be categorised as microplastics, which is tested herein by taking an example of a compostable plastic that is used as a bin bag on our kitchen table to collect the food residues. Results First, we employ matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) to identify the main components of the bioplastic bag as polymer and starch. Next, we use Raman imaging to monitor the stability under laser illumination, in an oven at ~ 60 °C for ~ 2 weeks, or in the presence of tap water for half a year. Basically, the compostable plastic is stable under these conditions. Thirdly, however, once used as table-bin bag with involvement of food residues, within ~ 1 week, the bioplastic bag is broken and biodegraded to release debris. The derivate surface groups are effectively monitored and directly visualised via Raman imaging, and cross-checked with scanning electron microscope (SEM). The yielded small molecule such as formic acid is also identified, along with the released debris of microplastics, with the help of on-site extraction of the fragmented sample and imaging analysis algorithm of the hyper spectrum. Conclusions After one week, the bag in the waste bin fragments, releasing a significant amount of debris. This could pose a functional issue if users intend to use the bag for at least a week, and could become a potential environmental problem if the waste is dispersed uncontrollably. In general, further research is needed to potentially distinguish the persistent conventional microplastics from the bioplastic fragments, to effectively mitigate the plastic pollution. Graphical Abstract

Abstract Plastic consumption has increased globally, and environmental issues associated with it have only gotten more severe; as a result, the search for environmentally friendly alternatives has intensified. Polyhydroxyalkanoates (PHA), as biopolymers produced by microalgae, might be an excellent option; however, large-scale production is a relevant barrier that hinders their application. Recently, innovative materials such as carbon dots (CDs) have been explored to enhance PHA production sustainably. This study added green synthesized multi-doped CDs to Scenedesmus sp. microalgae cultures to improve PHA production. Prickly pear was selected as the carbon precursor for the hydrothermally synthesized CDs doped with nitrogen, phosphorous, and nitrogen–phosphorous elements. CDs were characterized by different techniques, such as FTIR, SEM, ζ potential, UV–Vis, and XRD. They exhibited a semi-crystalline structure with high concentrations of carboxylic groups on their surface and other elements, such as copper and phosphorus. A medium without nitrogen and phosphorous was used as a control to compare CDs-enriched mediums. Cultures regarding biomass growth, carbohydrates, lipids, proteins, and PHA content were analyzed. The obtained results demonstrated that CDs-enriched cultures produced higher content of biomass and PHA; CDs-enriched cultures presented an increase of 26.9% in PHA concentration and an increase of 32% in terms of cell growth compared to the standard cultures.

In this study, the impact of bioplastic design on anaerobic digestion for biogas production was investigated. This research aims to facilitate the integration of bioplastics into a circular economy, which is why our study proposes considering not only aspects related to their degradation in the formulation but also ensuring efficient behavior in anaerobic digestion plants. Thermoplastic starch (TPS) samples, derived from different starch sources and formulated with varying concentrations of calcium carbonate and thicknesses, were subjected to anaerobic digestion tests. Three key parameters were explored: the influence of filler concentration, the effect of sample thickness, and the role of starch origin. Biogas production and kinetics were assessed using biochemical methane potential (BMP) tests. The results reveal that calcium carbonate concentration negatively influenced the methane production rate, reaching 30 NmL/gVS/day for the filler-free sample, highlighting the importance of understanding filler effects on anaerobic digestion. Additionally, thicker samples exhibited slower biogas production, with a rate of 25 NmL/gVS/day compared to 30 NmL/gVS/day for the thinnest sample, emphasizing the relevance of sample thickness in influencing digestion kinetics. The starch origin did not yield significant differences in biogas production, providing valuable insights into the feasibility of using diverse starch sources in bioplastic formulations. This study enhances our understanding of bioplastic behavior during anaerobic digestion, offering essential insights for optimizing waste management strategies and advancing circular economy practices. [ABSTRACT FROM AUTHOR]

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 strain's 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. [ABSTRACT FROM AUTHOR]

• A large percentage of plastic is abandoned in the environment, reaching rivers and thus the sea. • Bioplastics have been introduced with the aim of partially replacing plastics and reduce pollution. • Test methods fail to establish a value for parameters to be met to define a substance as biodegradable. • Although biodegradable bioplastics are largely perceived to be a biodegradable material, a large amount is characterised by a widely varied degree of biodegradability. • The authors suggest including ecotoxic analysis of by-products in the presence of incomplete biodegradation. Bioplastics were first introduced as environmentally friendly materials, with properties similar to those of conventional plastics. A bioplastic is defined as biodegradable if it can be decomposed into carbon dioxide under aerobic degradation, or methane and CO 2 under anaerobic conditions, inorganic compounds, and new cellular biomass, by the action of naturally occurring microorganisms. This definition however does not provide any information on the environmental conditions, timescale and extent at which decomposition processes should occur. With regard to the aquatic environment, recognized standards have been established to assess the ability of plastics to undergo biodegradation; however, these standards fail to provide clear targets to be met to allow labelling of a bioplastic as biodegradable. Moreover, these standards grant the user an extensive leeway in the choice of process parameters. For these reasons, the comparison of results deriving from different studies is challenging. The authors analysed and discussed the degree of biodegradability of a series of biodegradable bioplastics in aquatic environments (both fresh and salt water) using the results obtained in the laboratory and from on-site testing in the context of different research studies. Biochemical Oxygen Demand (BOD), CO 2 evolution, surface erosion and weight loss were the main parameters used by researchers to describe the percentage of biodegradation. The results showed a large variability both in weight loss and BOD, even when evaluating the same type of bioplastics. This confirms the need for a reference range of values to be established with regard to parameters applied in defining the biodegradability of bioplastics. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to develop a value-added bio-based polymer product for food packaging. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a promising bioplastic with limitations in processability and brittleness, which our group previously addressed by incorporating high-molecular-weight natural rubber (NR) compatibilized with peroxide and coagent. Yet, processability in an industrial setting proved difficult. Coffee oil epoxide (COE), a waste-derived plasticizer, was incorporated into the PHBV/NR/peroxide/coagent matrix via extrusion, and properties of resulting sheets were evaluated. COE incorporation significantly decreased the oxygen and water permeability of the PHBV/NR sheets. Maximum degradation temperature Tpeak (°C) increased by ~4.6 °C, and degree of crystallinity decreased by ~15.5% relative to pristine PHBV, indicating good thermal stability. Melting (Tm) and glass transition temperatures (Tg) of the PHBV/NR blend remained unchanged with COE incorporation. X-ray diffraction (XRD) revealed ~10.36% decrease in crystal size for the plasticized blend. Energy-dispersive X-ray analysis (EDAX) and scanning electron microscopy (SEM) confirmed good dispersion with no phase separation. The water uptake capacity of the plasticized blend was reduced by 61.02%, while surface contact angle measurements showed improved water resistance. The plasticized PHBV sheet shows promise for environmentally friendly packaging films due to its high thermal stability, effective barrier properties, and industrial scalability. [ABSTRACT FROM AUTHOR]

Starch-based thermoplastic polymer is a biopolymer that is being widely explored as a replacement for conventional polymers. Since thermoplastic starch suffers from mechanical defects, certain mechanical and thermal properties of starch-based polymers can be improved by incorporating fillers or reinforcements derived mainly from natural substances. This article reports the preparation, physicochemical, and mechanical characterization and biodegradation of starch-based bioplastics extracted from potato (Solanum tuberosum) peels using glycerol (G) as plasticizer and reinforced with carob powder, a readily growing plant in Mediterranean climates. The present study investigates the effect of incorporating different proportions (0, 2, 5, 10, and 15 wt.%) of carob powder (Cb) in the films thus prepared. These biopolymer films were fully characterized using analytical techniques including Fourier transform infrared spectroscopy with attenuated total reflection (FTIR/ATR), thermogravimetric analysis (TGA/DTG), X-ray diffraction (XRD), optical microscopy (OM), Scanning electron microscopy (SEM), mechanical evaluations, and biodegradability assessments. The biodegradability of the obtained bioplastic samples was evaluated. Scanning electron microscopy (SEM) revealed strong interfacial adhesion between the constituent filler and the polymer matrix. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA) is a sustainable alternative to low-density polyethylene (LDPE), which is a major source of plastic waste. However, the barrier properties and mechanical strength of CA may limit its application as single-use food plastic packaging. This study aims to overcome these limitations by incorporating polyethylene glycol (PEG) 1450 ranging from 10 to 50% w/w. PEG 1450 improved water vapor barrier but increased moisture content, though both values remained similar up to 50% w/w PEG 1450. CA bioplastic films showed significantly higher (p < 0.05) UV–Vis absorbances at 40% w/w PEG 1450, suggesting that a high concentration of PEG 1450 can prevent lipid oxidation but also increase opacity as reflected on the physical appearance. The reduced transparency was caused by aggregation and physical exclusion of PEG 1450 from the CA matrix which was observed under a scanning electron microscope (SEM). Meanwhile, PEG 1450 was miscible and compatible with CA at low concentration. In terms of mechanical properties, inclusion of PEG 1450 at 10 and 20% w/w improved the tearability of CA bioplastic films. In short, the incorporation of PEG 1450 improved barriers against UV and water vapor and tearability, making it superior to commercial LDPE plastic in some respects but lacking in others. Nonetheless, its advantages make it suitable for producing single-use food packaging, hence potentially replacing LDPE. [ABSTRACT FROM AUTHOR]

The replacement of expensive components in microbial growth media with pretreated lignocellulosic waste component to increase the product spectrum and add value to the bioproducts has been encouraged to achieve sustainable and feasible utilization of waste biomass as per the biorefinery approach. This study demonstrates an integrated biorefinery approach towards utilization of sugarcane bagasse and biomass of Mucor circinelloides ZSKP. A maximum reducing sugar recovery of 80.67 g/l was achieved after combining pretreatment with saccharification. A low temperature, glycerol, and ammonium phosphate pretreatment method was established, where glycerol pretreatment conditions were reduced from 250 to 150 °C and from 120 to 45 min. The ammonium phosphate-containing hydrolysate yielded 12.89 g/l of fungal biomass after fermentation to add to 20.8 g lignin from the delignification step. The biomass production was further improved to 17.69 g/l after supplementation with corn steep solids and mineral salts. The fermentation process also yielded 2.36 g/l chitosan and 4.9 g/l of lipids after extraction from the oleaginous fungus. The lignin infused glycerol plasticized chitosan biocomposite plastic had a 100% improvement in thermogravimetric properties with almost 50% more energy needed to increase the temperature of the material when compared to glycerol only plasticized biocomposite. The fungal chitosan showed antimicrobial properties and was effective as a preservative spray for fresh tomatoes and apples extending their shelf life to at least 14 and 18 days, respectively. This study therefore demonstrated that a novel two-step pretreatment process could be environmentally beneficial and yielded multiple products for biotechnological applications. [ABSTRACT FROM AUTHOR]

Fish gelatin is a promising polymer for creating plastics derived from agro-industrial waste, offering a sustainable alternative to single-use plastics. This research aimed to develop fish gelatin films that can be used to replace conventional single-use plastics employed in food packaging. Specifically, our focus was on reducing the high hydrophilic behavior of fish gelatin films which limits their possible applications. To address this, mono-, bi-, and tri- layer films were fabricated from fish gelatin and amylopectin. The fish gelatin was cross-linked with the enzyme transglutaminase to reduce its hydrophilicity achieving two levels of cross-linking: 40 ± 2%, and 65 ± 4%. Micrographs confirmed crack-free films and bilayer/trilayer formation. The cross-linked films exhibited reduced solubility: about 30% in monolayer and 40–67% in bilayer and trilayer films compared to pure protein films. Regarding the water vapor transmission rate, the highly cross-linked trilayer film displayed a value of 0.95 g/m2 h which is significantly lower than pure protein films (2.89 g/m2 h) and amylopectin films (9.37 g/m2 h). Additionally, Young's modulus and the thermal stability were improved with the lamination. These results suggest an effective method for manufacturing films from fish waste, which could contribute to a circular economy for the fishing industry. Enhanced water resistance also makes the films potentially suitable for sustainable biopolymer-based active food packaging. [ABSTRACT FROM AUTHOR]

[Display omitted] • Impact of PLA contamination in the waste stream of HDPE recycling was explored. • PLA contamination of even 1 wt% can significantly affect the end product quality. • Understanding the impact of UVA exposure is essential for durability analysis. • HDPE contaminated with PLA is more susceptible to photodegradation. • The surface morphology of the blended polymers shows notable imperfections. Quality assurance of a recycled product is currently one of the biggest issues that the plastic recycling industry faces. The purity of the input plastic waste stream has significant influence over the quality of the recycled product. This research evaluated the impact of polylactic acid (PLA) contamination within the input waste stream of high-density polyethylene (HDPE) recycling. The ultimate tensile strength was noted to reduce by 50% when PLA contamination was at 10%. An investigation into the effect that UVA radiation (simulating solar radiation) has on HDPE contaminated with PLA was also performed to determine the long-term effect of the bioplastic contamination. After UVA treatment, the ultimate tensile strength was reported to reduce by 51% when PLA contamination was only at 2.5%. A water contact angle analysis indicated the PLA contamination increased the hydrophilic nature of the HDPE sheets, potentially creating issues if the intended use of the recycled product was to store liquids. Microscopic analysis of the HDPE sheets contaminated with PLA showed deformations, ridges, cracks, and holes appear on the surface due to the immiscibility of the two polymers that was confirmed by FTIR analysis. Colour changes were visibly noted, with UVA exposure increasing the rate of colour change. Based on the findings in this study, PLA contamination of even 1% in a HDPE waste stream would significantly reduce the quality of the recycled product. [ABSTRACT FROM AUTHOR]

Poly(3-hydroxybutyrate) (P(3HB)) is an attractive biodegradable plastic alternative to petroleum-based plastic. However, the cost of microbial-based bioplastic production mainly lies in the cultivation medium. In this study, we screened the isolates capable of synthesizing P(3HB) using sugarcane bagasse (SCB) waste as a carbon source from 79 Bacillus isolates that had previously shown P(3HB) production using a commercial medium. The results revealed that isolate S356, identified as Bacillus cereus using 16S rDNA and gyrB gene analysis, had the highest P(3HB) accumulation. The highest P(3HB) yield (5.16 g/L, 85.3% of dry cell weight) was achieved by cultivating B. cereus S356 in an optimal medium with 1.5% total reducing sugar with SCB hydrolysate as the carbon source and 0.25% yeast extract as the nitrogen source. Transmission electron microscopy analysis showed the accumulation of approximately 3–5 P(3HB) granules in each B. cereus S356 cell. Proton nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy analyses confirmed that the polymer extracted from B. cereus S356 was P(3HB). Notably, during cultivation for P(3HB) plastic production, B. cereus S356 also secreted bacteriocin, which had high antibacterial activity against the same species (Bacillus cereus). Overall, this work demonstrated the possibility of co-producing eco-friendly biodegradable plastic P(3HB) and bacteriocin from renewable resources using the potential of B. cereus S356. [ABSTRACT FROM AUTHOR]

Plastic has become part of daily life because it is used in all industrial applications. Although it is beneficial and practical, it is the material that generates the most pollution in ecosystems. Therefore, the main objective of this research is to produce plastic films capable of degrading the environment in a shorter time (bioplastics). For this purpose, different samples were made with cassava starch (pulp or commercial), using amounts in the solution of 4% w/v and 30% w/w of cassava starch and glycerol, respectively, considering variations between the percentages of chitosan. The results showed that it is possible to obtain bioplastic by the casting method with the mixture of cassava starch (pulp or commercial), glycerol, and chitosan. Likewise, thanks to the laboratory tests carried out, was possible to determine that the use of commercial starch to produce biodegradable plastic films significantly favors moisture adsorption, solubility, and biodegradability, compared to starch extracted from cassava by hand, with good statistics validity of the analyzed data. [ABSTRACT FROM AUTHOR]

Background: Plastic is widely utilized in packaging, frameworks, and as coverings material. Its overconsumption and slow degradation, pose threats to ecosystems due to its toxic effects. While polyhydroxyalkanoates (PHA) offer a sustainable alternative to petroleum-based plastics, their production costs present significant obstacles to global adoption. On the other side, a multitude of household and industrial activities generate substantial volumes of wastewater containing both organic and inorganic contaminants. This not only poses a threat to ecosystems but also presents opportunities to get benefits from the circular economy. Production of bioplastics may be improved by using the nutrients and minerals in wastewater as a feedstock for microbial fermentation. Strategies like feast-famine culture, mixed-consortia culture, and integrated processes have been developed for PHA production from highly polluted wastewater with high organic loads. Various process parameters like organic loading rate, organic content (volatile fatty acids), dissolved oxygen, operating pH, and temperature also have critical roles in PHA accumulation in microbial biomass. Research advances are also going on in downstream and recovery of PHA utilizing a combination of physical and chemical (halogenated solvents, surfactants, green solvents) methods. This review highlights recent developments in upcycling wastewater resources into PHA, encompassing various production strategies, downstream processing methodologies, and techno-economic analyses. Short conclusion: Organic carbon and nitrogen present in wastewater offer a promising, cost-effective source for producing bioplastic. Previous attempts have focused on enhancing productivity through optimizing culture systems and growth conditions. However, despite technological progress, significant challenges persist, such as low productivity, intricate downstream processing, scalability issues, and the properties of resulting PHA. [ABSTRACT FROM AUTHOR]

This research delves into a detailed exploration of the thermal decomposition behavior of bio-based polymers, specifically thermoplastic starch (TPS) and polylactic acid (PLA), under varying heating rates in a nitrogen atmosphere. This study employs thermogravimetry (TG) to investigate, providing comprehensive insights into the thermal stability of these eco-friendly polymers. In particular, the TPS kinetic model is examined, encompassing the decomposition of three distinct fractions. In contrast, PLA exhibits a simplified kinetic behavior requiring only a fraction described by a zero-order model. The kinetic study involves a systematic investigation into the individual contributions of key components within TPS, including starch, glycerin, and polyvinyl alcohol (PVA). This detailed analysis contributes to a comprehensive understanding of the thermal degradation process of TPS and PLA, enabling the optimization of processing conditions and the prediction of material behavior across varying thermal environments. Furthermore, the incorporation of different starch sources and calcium carbonate additives in TPS enhances our understanding of the polymer’s thermal stability, offering insights into potential applications in diverse industries. [ABSTRACT FROM AUTHOR]

Polymer filament fabrication and its printability are influenced significantly by rheological behavior. This influence can pose a significant obstacle when attempting to transition fused deposition modeling (FDM) from the laboratory to industrial or clinical settings. The aim of this study is to demonstrate how machine learning (ML) approaches can speed up the development of polymer filaments for FDM. Four types of ML methods: artificial neural network, support vector regression, polynomial chaos expansion (PCE), and response surface model, were used to predict the rheological behaivior of polybutylene succinate. In general, all four approaches presented significantly high correlation values with respect to the training and testing data stages. Remarkably, the PCE algorithm repeatedly provided the highest correlation for each response variable in both the training and testing stages. Noteworthy, variation differs between response variables rather than between algorithms. Taken together, these modeling approaches could be used to optimize filament extrusion processes. [ABSTRACT FROM AUTHOR]

Plastic waste is increasingly piling up because it is not easily destroyed by rain, sunlight, or microbes that live in the soil, thereby it increases environmental damage such as soil pollution. One of the solutions to overcome the problem of using plastic is bioplastic technology. In this study, we aimed to prepare and characterize the physicochemical of bioplastics from different vegetable waste such as green spinach (GS), water spinach (WS), and moringa (M). The preparation of bioplastics was carried out with two variants: the vegetable waste as the base material/PVA and coating with polyeugenol (PEU). Physicochemical analysis of bioplastics includes surface observation by scanning electron microscopic (SEM); crystallinity by X-Ray diffraction (XRD); identification of functional groups by Fourier transform infra-red (FTIR); thermal characteristics analysis by thermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimetric (DSC); and analysis of mineral composition by atomic absorption spectroscopy (AAS) techniques. Analysis by SEM showed that the smoothest surface was WS/PVA coating with polyeugenol (PEU) compared with other vegetable waste. The characterization results showed that the obtained bioplastic had good heat resistance up to 200 °C. XRD analysis showed that vegetable waste/PVA coated with PEU increases the crystallinity and the highest crystallinity value was M/PVA coated with PEU. The FTIR results showed the presence of C-H alkanes, C=O carboxylic acids, OH alcohols, and C-H alkenes and the spectra are similar between GS, WS, and M. Analysis by AAS showed that the bioplastic produced contained some micro and macronutrients including Ca, Cu, Fe, K, Mg, Mn, Na, and Ni and only the mineral Cu was not found in M. Thus, bioplastic from vegetable waste/PVA and coating with PEU were potentially used as mulch and packaging material. [ABSTRACT FROM AUTHOR]

Background: Plastic is generating global pollution and the replacement such as bioplastic has been developed to mitigate the pollution. To this end, the fate, transformation and pathway of bioplastics need more research. For example, the fragmentation of bioplastic can release small debris that can be categorised as microplastics, which is tested herein by taking an example of a compostable plastic that is used as a bin bag on our kitchen table to collect the food residues. Results: First, we employ matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) to identify the main components of the bioplastic bag as polymer and starch. Next, we use Raman imaging to monitor the stability under laser illumination, in an oven at ~ 60 °C for ~ 2 weeks, or in the presence of tap water for half a year. Basically, the compostable plastic is stable under these conditions. Thirdly, however, once used as table-bin bag with involvement of food residues, within ~ 1 week, the bioplastic bag is broken and biodegraded to release debris. The derivate surface groups are effectively monitored and directly visualised via Raman imaging, and cross-checked with scanning electron microscope (SEM). The yielded small molecule such as formic acid is also identified, along with the released debris of microplastics, with the help of on-site extraction of the fragmented sample and imaging analysis algorithm of the hyper spectrum. Conclusions: After one week, the bag in the waste bin fragments, releasing a significant amount of debris. This could pose a functional issue if users intend to use the bag for at least a week, and could become a potential environmental problem if the waste is dispersed uncontrollably. In general, further research is needed to potentially distinguish the persistent conventional microplastics from the bioplastic fragments, to effectively mitigate the plastic pollution. [ABSTRACT FROM AUTHOR]

Seaweed, a diverse and abundant marine resource, holds promise as a renewable feedstock for bioplastics due to its polysaccharide-rich composition. This review explores different methods for extracting and processing seaweed polysaccharides, focusing on the production of alginate plastic materials. Seaweed emerges as a promising solution, due to its abundance, minimal environmental impact, and diverse industrial applications, such as feed and food, plant and soil nutrition, nutraceutical hydrocolloids, personal care, and bioplastics. Various manufacturing techniques, such as solvent casting, injection moulding, and extrusion, are discussed for producing seaweed-based bioplastics. Alginate, obtained mainly from brown seaweed, is particularly known for its gel-forming properties and presents versatile applications in many sectors (food, pharmaceutical, agriculture). This review further examines the current state of the bioplastics market, highlighting the growing demand for sustainable alternatives to conventional plastics. The integration of seaweed-derived bioplastics into mainstream markets presents opportunities for reducing plastic pollution and promoting sustainability in material production. [ABSTRACT FROM AUTHOR]

This article aims to understand the role of institutions, especially meso-institutions, in the construction of definitions of bioplastics that foster sociotechnical changes, so that a single language with epistemic quality can be defined for global governance in the solution of environmental problems arising from the plastic production chain. To this end, through a narrative literature review and documentary research on European and Brazilian legislation, this article applies theory to the case of the global definition of bioplastics. Clearly, the creation of definitions matters to institutions and global governance, since they ensure that these definitions follow the criteria of coherence, determination and epistemic quality. On the other hand, it is noted that these criteria are not met in the case of the definition of bioplastics, which suffers from a lack of global standardization. Furthermore, we conclude that the lack of a globally standardized definition of bioplastics promotes negative effects, such as greenwashing. Critical topics such as renewable contents and the biodegradability and compostability of materials are essential to a deeper comprehension of sustainability. From this perspective, this study highlights the intricate interplay between technological advancements and established standards in the rapidly evolving bioplastic market, which is underscored by a lack of clear definitions. Meso-institutions emerge as pivotal actors in bridging the gap between market demands and scientific progress that facilitate the development of standards and regulations essential to the sustainable dissemination of bioplastics. [ABSTRACT FROM AUTHOR]

Plastic consumption has increased globally, and environmental issues associated with it have only gotten more severe; as a result, the search for environmentally friendly alternatives has intensified. Polyhydroxyalkanoates (PHA), as biopolymers produced by microalgae, might be an excellent option; however, large-scale production is a relevant barrier that hinders their application. Recently, innovative materials such as carbon dots (CDs) have been explored to enhance PHA production sustainably. This study added green synthesized multi-doped CDs to Scenedesmus sp. microalgae cultures to improve PHA production. Prickly pear was selected as the carbon precursor for the hydrothermally synthesized CDs doped with nitrogen, phosphorous, and nitrogen–phosphorous elements. CDs were characterized by different techniques, such as FTIR, SEM, ζ potential, UV–Vis, and XRD. They exhibited a semi-crystalline structure with high concentrations of carboxylic groups on their surface and other elements, such as copper and phosphorus. A medium without nitrogen and phosphorous was used as a control to compare CDs-enriched mediums. Cultures regarding biomass growth, carbohydrates, lipids, proteins, and PHA content were analyzed. The obtained results demonstrated that CDs-enriched cultures produced higher content of biomass and PHA; CDs-enriched cultures presented an increase of 26.9% in PHA concentration and an increase of 32% in terms of cell growth compared to the standard cultures. [ABSTRACT FROM AUTHOR]

Environmental friendly biocomposites are urgently needed to mitigate the pollution caused by huge consumption of petroleum-based polymers. Renewable carrageenan and polylactic acid (PLA) natural polymers have the potential to replace petroleum-origin polymers. Nevertheless, the carrageenan and PLA themselves inherit poor tensile strength, hydrophobicity and stability. The aim of this study is to underpin the mechanism of synthesis of carrageenan-PLA biocomposite using van't Hoff plot, 1HNMR and density functional theorem simulation. Strong hydrogen bonding was found at 1.88 Å between O atom (carrageenan) and H atom (PLA) and was validated in 1HNMR shifting at 5.3 ppm corresponding to –OH group from PLA. The interaction established in the biocomposite mixed at 50 °C leads to a stronger tensile strength of 75.37 MPa, higher hydrophobicity and thermal stability with highest activation energy of 45.39 kJ/mol. The biocomposite produced from renewable carrageenan-PLA material would be a future replacement for nondegradable plastic as a food packaging material. [ABSTRACT FROM AUTHOR]

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Polyhydroxyalkanoate (PHA) polymers are environmentally friendly alternatives to conventional plastics. In support of a circular bioeconomy, they can be produced by growing microbial strains in waste materials, including lignocellulosic biomass, such as Canola fines (straw). In this study, PHA and polyhydroxybutyrate (PHB) production by a selection of seven wild-type actinobacterial strains, including three strains of Gordonia species, were assessed. When grown in defined media and hydrolysates of Canola fines, the highest amounts of PHB were produced by Nocardia gamkensis CZH20T (0.0476 mg/mL) and Gordonia lacunae BS2T (0.0479 mg/mL), respectively. Six strains exhibited a substrate preference for cellobiose over glucose, xylose, and arabinose in the hydrolysates. Analysis of Fourier transform infrared spectra indicated that the strains produced co-polymers of short- and medium-chain-length PHAs. None of the core phaABC genes were found on defined operons in the genomes of the top PHB-producing strains (all Gordonia strains, N. gamkensis CZH20T, and Streptomyces sp. strain HMC19). The Gordonia strains all harbored three phaA genes, a single phaB gene, and, with the exception of strain BG1.3 (with two predicted phaC genes), a single phaC gene. Predictive analyses of the proteins likely to be translated from the phaC genes revealed PhaC proteins of 37.7–39.2 kDa from Gordonia sp. strain BG1.3, G. lacunae BS2T, and N. gamkensis CZH20T; PhaC proteins of 106.5–107 kDa from Gordonia sp. strain JC51; and the second PhaC from Gordonia sp. strain BG1.3 and N. gamkensis CZH20T, possibly representing a new class of PHA synthases. [ABSTRACT FROM AUTHOR]

Citrus waste has been used as a source of bioplastics for research in different ways. Because the juice industry produces significant amounts of residue each year, it would be advantageous to use the byproducts in the creation of new materials. Researchers have long explored eco-friendly methods to convert citrus and other organic waste into polymers for producing biodegradable films. The goal of this study is to create biofilms from orange waste (OW) and ginger waste (GW) using an ultrafine grinder and study the films' properties. Since pectin has the ability to gel, and because cellulosic fibers are strong, citrus waste has been studied for its potential to produce biofilms. After being washed, dried, and milled, orange and ginger waste was shaped into films using a casting process. Tensile testing was used to determine the mechanical properties of biofilms, while dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) were used to determine their thermal properties. As the number of grinding cycles increased, the suspension's viscosity increased from 29 mPa.s to 57 mPa.s for OW and from 217 mPa.s to 376 mPa.s for GW, while the particle size in the suspension significantly decreased. For OW and GW films, the highest tensile strength was 17 MPa and 15 MPa, respectively. The maximum strain obtained among all films was 4.8%. All the tested films were stable up to 150 °C, and maximum degradation occured after 300 °C. [ABSTRACT FROM AUTHOR]

Microplastics are described as plastic particles smaller than 5 mm in size. Nowadays they are making an increasingly prevalent environmental issue as generated by a variety of products. Microplastics are diagnosed in various environmental compartments like soil, water, and air and affect the quality of them. Manta nets, dust samplers, shawls, trawl etc. the sampling equipment are used. They are identified and characterised by Visual identification, FTIR, SEM, RAMAN etc. This review paper addresses the origins, sources, distribution, adverse impacts and potential hazards of microplastics on the environment and living beings andidentification and quantification methods in environmental samples. Also, emphasis on Nanoparticle-mediated degradation of microplasticswith titanium dioxide, iron oxide, and zinc oxide via surface adsorption and ROS generation. Integrating nanoparticles into bioplastic degradation enhances efficiency, offering multifaceted solutions for a cleaner, sustainable future. [ABSTRACT FROM AUTHOR]