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The usage of timed artificial insemination (TAI) at a low cost leading to better reproductive rates has been the aim of several research groups in the field. Usually during TAI protocols, sustained progesterone (P 4 ) release devices are employed. Most devices are constituted of a nylon skeleton covered with a silicon layer with P 4 . A device based on biopolymers was developed in order to reduce costs and decrease its environmental impact. In this study, we compared the kinetics of sustained progesterone release among devices manufactured with a polymeric blend made of polyhydroxybutyrate-valerate (PHBV) and poly-ε-caprolactone (PCL) (DISP) which were compared with DIB® (Internal Bovine Device) used as the control. In the in vitro and in vivo progesterone release tests, two types of biopolymer-based devices with a superficial area of 147 cm 2 were used: DISP8 (46% PHBV, 46% PCL and 8% P 4 ; n = 4), DISP10 (45% PHBV, 45% PCL, 10% P 4 ; n = 4) and DIB® (1 g P 4 , 120 cm 2 area; n = 3). The in vitro tests were carried out according to USP XXIII specifications and were performed in a dissolutor sink using an alcohol/water mixture (60/40 v/v) as a release media and samples were collected at 2 min, 2, 4, 8, 12, 24, 48, 60, 72, 84 and 96 h. P 4 concentrations were measured through spectrophotometry in a 244 nm long wave. Three to 3 comparisons of angular coefficients of the straight lines obtained by regression analysis of accumulated P 4 concentrations as a function of square root of time were carried out. Furthermore, the diffusion coefficient values of P 4 were also determined for DISP8 and DISP10. The results showed that the concentrations of P 4 were higher in the DISP10 (774.63 ± 45.26 μg/cm 2 /t 1 /2 ) compared to DISP8 (566.17 ± 3.68 μg/cm 2 /t 1 /2 ) (P < 0.05). However, both DISP10 and DISP8 P 4 concentrations did not differ from DIB® (677.39 ± 16.13 μg/cm 2 /t 1 /2 ). For the analysis of released quantities per day of the in vitro test, four periods were considered: 0-24, 24-48, 48-72 and 72-96 h. In the first 24 h, DISP8 released significantly less P 4 than DISP10 or DIB®, which did not differ among them. Between 24 and 48 h, DISP10 released significantly more P 4 than DIB®. DISP8 released an intermediate P 4 amount and did not differ significantly from DIB® or DISP10. Between 48 and 72 h, P 4 quantity released by DISP10 was significant higher (P < 0.01) than that of DIB® and DISP8, which did not differ among themselves. Between 72 and 96 h, DISP10 released significantly more P 4 than DIB®, and DISP8 released an intermediate amount which did not differ from DIB® or DISP10 (P < 0.01). There was interaction between treatment and time (P = 0.0024). The diffusion coefficient values were: 1.36 × 10 -8 (cm 2 /s) for DISP10 and 1.12 × 10 -8 (cm 2 /s) for DISP8. For the in vivo test, ovariectomized crossbred cows received DIB® (n = 4) or DISP8 (n = 8) in an alternate design with a non-balanced sequence (cross-over) added of measures repeated in time referring to 16 days of blood samples collection. Samples were analyzed through radioimmunoassay in solid phase using the commercial kit of DPC (Diagnostics Products Corporation). Plasma concentrations of P 4 concentrations above 1 ng/mL in the plasma of the cow during the 16 day in vivo test. In conclusion, devices manufactured with the blend of PHBV/PCL biopolymers can sustain the release of P 4 concentrations differed between DIB® (11.45 ± 1.96) compared with DISP8 (9.23 ± 1.15 ng/mL) (P = 0.027). On day 8, plasma P 4 concentrations were similar for DIB® (2.44 ± 0.09) and DISP8 (1.89 ± 0.13 ng/mL) (P = 0.58) showing that both devices were able to keep P 4 concentrations above 1 ng/mL in the plasma of the cow during the 16 day in vivo test. In conclusion, devices manufactured with the blend of PHBV/PCL biopolymers can sustain the release of P 4 in a similar manner as silicon., (© 2017 Japanese Society of Animal Science.)

The polyhydroxyalkanoate (PHA) copolymers consisting of short-chain-length (scl) and medium-chain-length (mcl) monomers have various properties ranging from stiff to flexible depending on the molar fraction of the monomer compositions. It has been reported that PhaG, which is first known as a (R)-3-hydroxyacyl-acyl carrier protein (ACP)-CoA transferase, actually functions as a 3-hydroxyacyl-ACP thioesterase, and the product of PP0763 gene from Pseudomonas putida KT2440 has a (R)-3-hydroxyacyl (3HA)-CoA ligase activity (Wang et al., Appl. Environ. Microbiol., 78, 519-527, 2012). In this study, we found a new (R)-3HA-CoA ligase (the product of PA3924 gene) from Pseudomonas aeruginosa PAO. The PA3924 gene was coexpressed with PHA synthase 1 gene (phaC1Ps) and phaGPs gene from Pseudomonas sp. 61-3, and β-ketothiolase gene (phbARe) and acetoacetyl-CoA reductase gene (phbBRe) from Ralstonia eutropha in Escherichia coli LS5218 at 25°C. As a result, the copolymer containing 94.6 mol% 3-hydroxybutyrate (3HB) and 5.4 mol% mcl-3-hydroxyalkanoates (3HA) consisting of C8, C10, C12 and C14 was synthesized by recombinant E. coli LS5218 from glucose as the sole carbon source. The concentration of P(3HB-co-3HA) (scl-co-mcl-PHA) synthesized by the recombinant E. coli LS5218 harboring phaC1Ps, phaGPs, phbABRe and the PA3924 genes was approximately 7-fold higher than that of the recombinant LS5218 harboring phaC1Ps, phaGPs, phbABRe and the PP0763 genes. The number-average molecular weight of the P(3HB-co-5.4% 3HA) copolymer was 233 × 10(3), which was relatively high molecular weight. In addition, the physical and the mechanical properties of the copolymer were demonstrated to improve the brittleness of P(3HB) homopolymer., (Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Increasing human population demands more usage of consumable items thus causes more destruction to the environment by developing advanced materials and technologies. Synthetic plastic is one of the most used material in daily life which results in accumulation of non-degradable waste material that stays in the environment for thousands of years and creates plastic pollution. Many species on the earth suffer from pollution caused by plastic and it is one of the leading causes of global warming. For sustainable development, we need to protect our environment from plastic pollution by making use of biodegradable materials. In the past few years, biodegradable materials with plastic like properties have gained much attention. They have been made from biomass such as sugarcane, corn, wheat, rice, banana peels, etc. Such desirable properties are also present in PHAs (polyhydroxyalkanoates) synthesized by microorganisms. Several types of PHAs have been discovered from bacteria and used as a bioplastic candidate. However, there are major challenges also such as high production cost and expensive raw material which limits its commercial applications. Modern tools and strategies have allowed precise metabolic engineering of various microorganisms to produce PHAs using highly efficient microbial cell factories. This review article focuses on the research done on the microbial bioplastic production and its various applications. We have also discussed the future perspectives of bioplastic for sustainable development. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHA) are popular biopolymers due to their potential use as biodegradable thermoplastics. In this study, three aerobic sequencing batch reactors were operated identically except for their temperatures, which were set at 15 °C, 35 °C, and 48 °C. The reactors were subjected to a feast-famine feeding regime, where carbon sources are supplied intermittently, to enrich PHAaccumulating microbial consortia. The biomass was sampled for 16S rRNA gene amplicon sequencing of both DNA (during the enrichment phase) and cDNA (during the enrichment and accumulation phases). All temperatures yielded highly enriched PHA-accumulating consortia. Thermophilic communities were significantly less diverse than those at low or mesophilic temperatures. In particular, Thauera was highly adaptable, abundant, and active at all temperatures. Low temperatures resulted in reduced PHA production rates and yields. Analysis of the microbial community revealed a collapse of community diversity during low-temperature PHA accumulation, suggesting that the substrate dosing strategy was unsuccessful at low temperatures. This points to future possibilities for optimizing low-temperature PHA accumulation. [ABSTRACT FROM AUTHOR]

In recent years, there has been increasing interest in developing novel materials based on natural biopolymers as a renewable alternative to petroleum-based plastics. The availability of proteins derived from agricultural by-products, along with their favourable properties, has fostered a renewed interest in protein-based materials, promoting research in innovative technologies. In this study, we propose the use of rapeseed protein-rich meal as the main ingredient for the preparation of novel sustainable materials combining excellent environmental properties such as biodegradability and renewability. The application of sustainable products in the present high-tech society requires the modification of the basic native properties of these natural compounds. The original route proposed in this paper consists of preparation via the compression moulding of flexible biomaterials stabilized by crosslinkers/chain extenders. An investigation of the effects of different denaturing and disulfide bond reducing agents, crosslinkers, and preparation conditions on the material mechanical behaviour demonstrated that the novel materials have appreciable strength and stiffness. The results show the potential of utilizing full meal from vegetable by-products to prepare protein-based materials with guaranteed ecofriendly characteristics and mechanical properties adequate for specific structural applications. [ABSTRACT FROM AUTHOR]

Biopolymers are highly desirable alternatives to petrochemical-based plastics owing to their biodegradable nature. The production of bioplastics, such as polyhydroxyalkanoates (PHAs), has been widely reported using various bacterial cultures with substrates ranging from pure to biowaste-derived sugars. However, large-scale production and economic feasibility are major limiting factors. Now, using algal biomass for PHA production offers a potential solution to these challenges with a significant environmental benefit. Algae, with their unique ability to utilize carbon dioxide as a greenhouse gas (GHG) and wastewater as feed for growth, can produce value-added products in the process and, thereby, play a crucial role in promoting environmental sustainability. The sugar recovery efficiency from algal biomass is highly variable depending on pretreatment procedures due to inherent compositional variability among their cell walls. Additionally, the yields, composition, and properties of synthesized PHA vary significantly among various microbial PHA producers from algal-derived sugars. Therefore, the microalgal biomass pretreatments and synthesis of PHA copolymers still require considerable investigation to develop an efficient commercial-scale process. This review provides an overview of the microbial potential for PHA production from algal biomass and discusses strategies to enhance PHA production and its properties, focusing on managing GHGs and promoting a sustainable future. [ABSTRACT FROM AUTHOR]

The escalating worldwide concerns over the difficult degradation and pollution of plastic and its associated environmental and health risks have amplified the urgent need to develop biodegradable alternatives to traditional plastics. Polyhydroxyalkanoates (PHAs) have emerged as a promising class of biopolymers that offer a sustainable solution. Their commercial success in various applications has highlighted PHAs' potential to mitigate environmental impact. Critical to the economic feasibility of PHA production is the optimization of downstream processing methods, crucial for scaling operations from pilot to industrial scales. This paper reviews two decades of pilot-scale studies on PHA extraction, emphasizing the advancements and challenges encountered. It also discusses chemical extraction methods applied across different feedstock and microbial strains, highlighting their role in enhancing efficiency and sustainability. This comprehensive review underscores the imperative for advancing PHA technologies, particularly in refining extraction techniques, to facilitate broader adoption in industries seeking environmentally friendly alternatives to conventional plastics. [ABSTRACT FROM AUTHOR]

The use of biodegradable polymers in the plastics industry has been increasing in recent years. The study of the chemical, physical, thermal, and mechanical properties of films based on biodegradable components is of interest to technologists because these properties determine their applicability for food packaging. In this work, films based on natural polymers such as linseed mucilage (LM) and chitosan (CH), as well as poly(acrylic acid) (PAA) were obtained through the casting method and using V‐50 as the initiator. The films were characterized through Fourier Transform Infrared spectroscopy, and thermogravimetric analysis, and their water absorption and swelling capacity, and thermal and mechanical properties were determined. Homogenous flexible, translucid, amber‐colored films, with low absorption and solubility in water were obtained. It was demonstrated through Fourier Transform Infrared analysis the chemical interaction between C–H, CO, and C–O chemical groups of LM, CH, and PAA. In addition, films showed high resistance to thermal decomposition between 125 and 425°C. The mechanical tests of tension allowed the composition of LM in the film, the behavior variates between a plastic and/or elastic material and with tensile strength (Rm) values between 10.8 and 16.4 MPa and elastic modulus (E) values between 56.2 and 169.2 GPa, we observed that at higher quantities of LM and thickness, both E and Rm tend to increase, while %EL decreases. This led us to conclude that the material transitioned from ductile and malleable to rigid and brittle. The films obtained with different ratios of LM/CH/PAA may exhibit a semi‐interpenetrating polymeric networking type morphology. Highlights: Thermal and mechanical properties are of interest in food packaging materials.Water absorption can impact the packaged food.Films can be processed on existing machines for conventional plastics.Some conventional plastics could be replaced by these biodegradable films.Biodegradable films are of great interest to the industry of food packaging. [ABSTRACT FROM AUTHOR]

Global concern about plastic pollution is forcing new policies and modifications of human consumption as well as promoting new research lines aiming at the replacement of non-degradable plastics with other polymers more environmentally friendly. Addressing food waste and promoting circular economy strategies, among other approaches, are crucial in reducing environmental impacts and fostering sustainability in several sectors like the agri-food industry. The European Union’s Circular Economy Action Plan is a significant initiative in this direction. Biotechnological processes, especially the valorisation of agri-food waste to produce highly marketed biomolecules like poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) using microorganisms as cellular factories, offer promising avenues for achieving these goals. PHBV is a biodegradable polymer firstly characterised as an isolated biopolymer from bacterial biomass. This biopolymer shows interesting physicochemical properties making possible immense potential in various applications due to its biocompatibility and sustainability, thus revealing it as a good candidate to replace plastics produced by chemical synthesis from petroleum (which are highly recalcitrant and consequently pollutants). This review critically analyses the PHBV synthesis and end-of-life scenarios from their synthesis using chemical and biological pathways, through the forms of biotechnological operation and production, to the forms described until the moment of recycling. [ABSTRACT FROM AUTHOR]

Today, 98% of all plastics are fossil-based and non-biodegradable, and globally, only 9% are recycled. Microplastic and nanoplastic pollution is just beginning to be understood. As the global demand for sustainable alternatives to conventional plastics continues to rise, biobased and biodegradable plastics have emerged as a promising solution. This review article delves into the pivotal concept of carbon recycling as a pathway towards achieving a zero-waste future through the production and utilization of high-value bioplastics. The review comprehensively explores the current state of bioplastics (biobased and/or biodegradable materials), emphasizing the importance of carbon-neutral and circular approaches in their lifecycle. Today, bioplastics are chiefly used in low-value applications, such as packaging and single-use items. This article sheds light on value-added applications, like longer-lasting components and products, and demanding properties, for which bioplastics are increasingly being deployed. Based on the waste hierarchy paradigm—reduce, reuse, recycle—different use cases and end-of-life scenarios for materials will be described, including technological options for recycling, from mechanical to chemical methods. A special emphasis on common bioplastics—TPS, PLA, PHAs—as well as a discussion of composites, is provided. While it is acknowledged that the current plastics (waste) crisis stems largely from mismanagement, it needs to be stated that a radical solution must come from the core material side, including the intrinsic properties of the polymers and their formulations. The manner in which the cascaded use of bioplastics, labeling, legislation, recycling technologies, and consumer awareness can contribute to a zero-waste future for plastics is the core topics of this article. [ABSTRACT FROM AUTHOR]

Polymer blends based on plastic waste and natural biodegradable polymers is an interesting strategy in view of environmental and technical concerns. This article investigates the structure, thermal and physical properties of virgin and post‐industrial polymethyl methacrylate (PMMA) waste/pristine chitosan (Cs) bio‐blends. Waste PMMA was generated by an extrusion process for the manufacturing of sheets. The results of gel permeation chromatography analysis (GPC) show a slight decrease (about 8%) in the average molecular weight of PMMA after extrusion. Fourier transform infrared spectroscopy in attenuated total reflectance mode (FTIR‐ATR) spectra do not reveal changes in the chemical structure of post‐industrial PMMA/Cs blends compared to virgin PMMA/Cs samples, indicating that chain scission reactions are the dominant degradation mechanism of PMMA during processing. Dynamic mechanical analysis (DMA) results reveal a single glass transition temperature (Tg) for the blends, implying miscibility of the components. Post‐industrial PMMA/Cs samples exhibit slightly lower values of Tg compared to virgin PMMA/Cs blends. The post‐industrial PMMA waste slightly reduces nano‐mechanical properties and thermal stability of the blends relative to those from virgin PMMA. In contrast, it increases the water uptake of the bio‐blends compared with virgin PMMA. Highlights: Chain scission is the dominant degradation mechanism of PMMA during extrusion.Miscibility between the homopolymers within the blends.PMMA waste slightly reduced the nano‐mechanical properties of the bio‐blends.Post‐industrial PMMA waste increased the water uptake of the bio‐blends.Possibility of using post‐industrial PMMA waste by blending with chitosan. [ABSTRACT FROM AUTHOR]

Approximately 50% of global plastic wastes are produced from plastic packaging, a substantial amount of which is disposed of within a few minutes of its use. Although many plastic types are designed for single use, they are not always disposable. It is now widely acknowledged that the production and disposal of plastics have led to a plethora of negative consequences, including the contamination of both groundwater and soil resources and the deterioration of human health. The undeniable impact of excessive plastic manufacturing and waste generation on the global plastic pollution crisis has been well documented. Therefore, degradable polymers are a crucial solution to the problem of the non-degradation of plastic wastes. The disadvantage of degradable polymers is their high cost, so blending them with natural polymers will reduce the cost of final products and maximize their degradation rate, making degradable polymers competitive with industrial polymers that are currently in use daily. In this work, we will delineate various degradable polymers, including polycaprolactone, starch, and cellulose. Furthermore, we will elucidate several aspects of polyvinyl alcohol (PVA) and its blends with natural polymers to show the effects of adding natural polymers on PVA properties. This paper will study cost-effective and ecologically acceptable polymers by combining inexpensive natural polymers with readily accessible biodegradable polymers such as polyvinyl alcohol (PVA). [ABSTRACT FROM AUTHOR]

The synthesis of conventional plastics has increased tremendously in the last decades due to rapid industrialization, population growth, and advancement in the use of modern technologies. However, overuse of these fossil fuel-based plastics has resulted in serious environmental and health hazards by causing pollution, global warming, etc. Therefore, the use of microalgae as a feedstock is a promising, green, and sustainable approach for the production of biobased plastics. Various biopolymers, such as polyhydroxybutyrate, polyurethane, polylactic acid, cellulose-based polymers, starch-based polymers, and protein-based polymers, can be produced from different strains of microalgae under varying culture conditions. Different techniques, including genetic engineering, metabolic engineering, the use of photobioreactors, response surface methodology, and artificial intelligence, are used to alter and improve microalgae stocks for the commercial synthesis of bioplastics at lower costs. In comparison to conventional plastics, these biobased plastics are biodegradable, biocompatible, recyclable, non-toxic, eco-friendly, and sustainable, with robust mechanical and thermoplastic properties. In addition, the bioplastics are suitable for a plethora of applications in the agriculture, construction, healthcare, electrical and electronics, and packaging industries. Thus, this review focuses on techniques for the production of biopolymers and bioplastics from microalgae. In addition, it discusses innovative and efficient strategies for large-scale bioplastic production while also providing insights into the life cycle assessment, end-of-life, and applications of bioplastics. Furthermore, some challenges affecting industrial scale bioplastics production and recommendations for future research are provided. [ABSTRACT FROM AUTHOR]

Nowadays, the world is facing a general problem of resource overconsumption and waste overproduction: to address these two issues, the United Nations delivered the 12th Sustainable Development Goal (SDG), which has the objective of ensuring sustainable consumption and production patterns. Currently, polymers are present in every aspect of our lives and have the disadvantage of mostly coming from fossil sources and causing pollution when disposed of the wrong way. Agriculture plays a key role in the overall world environmental issues, being responsible for the creation of between 13 and 21% of global greenhouse gas (GHG) emissions. Moreover, it represents a continuously growing field, producing large amounts of waste. These residues can cause serious environmental concerns and high costs when disposed. However, agri-food waste (AFW) is a natural source of natural biopolymers, such as lignin, cellulose, pectin, and starch, but can also be used as a substrate to produce other non-toxic and biodegradable biopolymers, such as chitosan, polyhydroxyalkanoates (PHAs), and polylactic acid (PLA) through microbial fermentation. These polymers find applications in agricultural practices such as mulching films, soil stabilizers, hydrogels, nanocarriers, and coating for seeds, fruits, and vegetables. The employment of AFW in the production of non-toxic, sustainable, and biodegradable biopolymers for their agricultural utilization is an example of a virtuous circular economy approach that could help agriculture to be more sustainable. [ABSTRACT FROM AUTHOR]

Severe plastics pollution derived from the wide use and the past incorrect dispersion of petroleum-based plastics. The development of bioplastics/biopolymers with the same chemical/physical characteristics of conventional plastics can be a solution to the problems of their degradability. Polybutylene succinate was among the most investigated biopolymers for these characteristics that can be produced from bio-based succinic acid and butan-1,4-diol. Succinic acid can be produced through fermentation process using microorganisms as Actinobacillus succinogenes that were able to utilise glucose from several sources as lignocellulosic biomasses. Lignocellulosic biomass can be ideal candidates for glucose supply but the processes to release fermentable sugars can produce inhibitors (acids and furans) of the biological processes for succinic acid production. The aim of this paper was to evaluate the growth of A. succinogenes for the production of succinic acid under acetic acid and furfural at different concentration on inoculum with preadaptation and without adaptation. The results highlighted that pre-inoculum adaptation was essential for the growth of the strain and succinic acid production that decreased strongly under the synergistic effect of acetic acid and furfural in the broth (63% inhibition rate of growth) respect to inoculum with pre-inoculum adaptation (29% inhibition rate of growth). [ABSTRACT FROM AUTHOR]

Polymeric materials undergo degradation when exposed to outdoor conditions due to the synergistic effects of sunlight, air, heat, and moisture. The degradation can lead to a decline in mechanical properties, fading, surface cracking, and haziness, attributed to the cleavage of the polymer chains and oxidation reactions. Accelerated weathering testing is a useful technique to evaluate the comparative photodegradation of materials within a reasonable timeframe. This review gives an overview of the different degradation mechanisms occurring in conventional plastics and bio-based materials. Case studies on accelerated weathering and its effect on the mechanical properties of conventional plastics and biocomposites are discussed. Different techniques for analysing volatile organic emissions (VOCs) have been summarized and studies highlighting the characterization of VOCs from aged plastics and biocomposites after aging have been cited. [ABSTRACT FROM AUTHOR]

Non-degradable plastics of petrochemical origin are a contemporary problem of society. Due to the large amount of plastic waste, there are problems with their disposal or storage, where the most common types of plastic waste are disposable tableware, bags, packaging, bottles, and containers, and not all of them can be recycled. Due to growing ecological awareness, interest in the topics of biodegradable materials suitable for disposable items has begun to reduce the consumption of non-degradable plastics. An example of such materials are biodegradable biopolymers and their derivatives, which can be used to create the so-called bioplastics and biopolymer blends. In this article, gelatine blends modified with polysaccharides (e.g., agarose or carrageenan) were created and tested in order to obtain a stable biopolymer coating. Various techniques were used to characterize the resulting bioplastics, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA)/differential scanning calorimetry (DSC), contact angle measurements, and surface energy characterization. The influence of thermal and microbiological degradation on the properties of the blends was also investigated. From the analysis, it can be observed that the addition of agarose increased the hardness of the mixture by 27% compared to the control sample without the addition of polysaccharides. In addition, there was an increase in the surface energy (24%), softening point (15%), and glass transition temperature (14%) compared to the control sample. The addition of starch to the gelatine matrix increased the softening point by 15% and the glass transition temperature by 6%. After aging, both compounds showed an increase in hardness of 26% and a decrease in tensile strength of 60%. This offers an opportunity as application materials in the form of biopolymer coatings, dietary supplements, skin care products, short-term and single-contact decorative elements, food, medical, floriculture, and decorative industries. [ABSTRACT FROM AUTHOR]

There are several physical and chemical methods for synthesizing nanomaterials, while the most appropriate techniques involve using green chemistry and eco-friendly material. Recently, green synthesized materials for different applications have gained attention as a result of their environmental friendliness and cost-effectiveness. Applying green synthesized nanoparticles (NPS) in food packaging has been extensively investigated. Biopolymers require filler to enhance the optical, barrier, thermal, antimicrobial, and mechanical properties of packaging. Biopolymer packaging incorporated with green synthesized NPs is expected to simultaneously enhance performance while reducing environmental damage. The current review article focuses on biopolymer films with bio (green)-synthesized nanomaterials and their effectiveness in reducing the negative environmental implications of synthetic packaging. It also covers the general concepts of green synthesis of NPs, their production methods, their performance, and characterization, and discusses the potential, performance and recent developments of bio-nanocomposite films/coatings in biodegradable food packaging. Recent reports and trends provide more insight into the impact of green synthesized nanomaterials on food packaging. [ABSTRACT FROM AUTHOR]

Due to the extensive application of petroleum-based plastics as packaging materials and problems related to their degradation/recycling, developing new solutions in the field of novel biopolymer-based materials has become imperative. Natural substitutes for synthetic polymers (starch, cellulose, chitosan) require modifications that enable their processing and provide them with additional properties (i.e., mechanical strength, controlled biodeterioration, antimicrobial and antioxidative activity). The antioxidant activity of natural packaging materials still requires further investigation. In this research paper, novel materials used for packaging perishable food susceptible to oxidizing agents were designed from potato starch (NS) reinforced with antioxidants such as dialdehyde starch (DS) and caffeic acid (CA)/quinic acid (QA). The use of spectroscopic techniques (ATR-FTIR, Raman) and X-ray diffraction allowed the examination of the chemical structure and arrangement of the blend and confirmed the component interactions. The film surface was examined by AFM. DS, functioning as a cross-linker, enhanced the film barrier as well as the mechanical and thermal properties, and it promoted starch amorphization when blended with other antioxidants. The antioxidant activity of caffeic acid was greater than that of quinic acid. Dialdehyde starch improves elasticity, whereas acids (particularly caffeic acid) influence film stiffness. A high susceptibility to biodegradation is valuable for potential eco-friendly packaging applications. [ABSTRACT FROM AUTHOR]

Cellulose is an abundant natural polymer and is thus promising for enforcing biobased plastics. A broader application of cellulose fibers as a filler in polymer composites is limited because of their hydrophilicity and hygroscopicity. The recent scientific literature on plasma methods for the hydrophobization of cellulose materials is reviewed and critically evaluated. All authors focused on the application of plasmas sustained in fluorine or silicon-containing gases, particularly tetrafluoromethane, and hexamethyldisiloxane. The cellulose materials should be pre-treated with another plasma (typically oxygen) for better adhesion of the silicon-containing hydrophobic coating. In contrast, deposition of fluorine-containing coatings does not require pre-treatment, which is explained by mild etching of the cellulose upon treatment with F atoms and ions. The discrepancy between the results reported by different authors is explained by details in the gas phase and surface kinetics, including the heating of samples due to exothermic surface reactions, desorption of water vapor, competition between etching and deposition, the influence of plasma radiation, and formation of dusty plasma. Scientific and technological challenges are highlighted, and the directions for further research are provided. [ABSTRACT FROM AUTHOR]

[Display omitted] Nanoparticle addition can expand bioplastic use, as the resultant nanocomposite features e.g., improved mechanical properties. It is generally hypothesised that the nanoparticle-polymer interaction strength is pivotal to reduce polymer dynamics within the interphasial region and beyond. Translating nanoscale phenomena to bulk properties is challenging, as traditional techniques that probe interphasial dynamics are limited to well-dispersed systems. Laser speckle imaging (LSI) enabled us to probe interphasial nanoscale dynamics of samples containing aggregated nanoparticles. We relate these LSI-derived relaxation times to bulk rheological properties at a micro scale. Nanocomposites with well-dispersed PDMS-coated titanium dioxide nanoparticles of ∼100 nm showed higher viscosities than nanocomposites containing aggregated PVP- and PAA-coated nanoparticles of 200–2000 nm. Within the interphasial region, nanoparticle addition increased relaxation times by a factor 101–102, reaching ultraslow relaxations of ∼103 s. While the viscosity increased upon nanoparticle loading, interphasial relaxation times plateaued at 5 wt% for nanocomposites containing well-dispersed nanoparticles and 10 wt% for nanocomposites containing aggregated nanoparticles. Likely, interphasial regions between nanoparticles interact, which is more prominent in systems with well-dispersed nanoparticles and at higher loadings. Our results highlight that, contrary to general belief, nanoparticle dispersion seems of greater importance for mechanical reinforcement than the interaction between polymer and particle. [ABSTRACT FROM AUTHOR]

This review provides a comprehensive overview of recent advances in biodegradable materials for sustainable food packaging applications. Biodegradable polymers offer an alternative to conventional plastics by undergoing decomposition into water, carbon dioxide, and biomass. Synthetic biopolymers like PLA, PHAs, and bio-based polyesters as well as natural biopolymers such as polysaccharides and proteins have shown promise as substitutes for non-biodegradable packaging. These materials provide sustainability, waste reduction, and carbon neutrality benefits. However, inferior barrier properties, low heat resistance, poor mechanical strength, and high costs are limitations. Strategies like plasticization, blending, nanomaterial reinforcement, and multilayer composite structures have expanded biopolymer applicability for various foods. Biodegradation and life cycle assessment studies have demonstrated their environmental advantages over conventional plastics. Addressing remaining challenges in collection logistics, composting infrastructure, costs, and functional performance will be crucial for widespread commercial adoption. Recent advances make biopolymer packaging poised to make major contributions to sustainable development in the food industry. [ABSTRACT FROM AUTHOR]

Polyhydroxy butyrate (PHB) is one of the best environment-friendly bioplastic alternatives for petroleum-based plastic due to its biodegradability. However, it has less commercial popularity owing to the high cost of downstream processing that involves repeated centrifugation and the use of costly harmful solvents, as well as a labor-intensive process. Hydrodynamic Cavitation (HC) offers easy and simple mechanisms for downstream processing. Also, biopolymer extracted for haloarchea show an advantage of least contamination under the halophilic condition on an industrial level. In this paper, a haloarchaeal consortium producing biopolymer isolated from commercial rock salt has been subjected to HC as well as distilled water lysis. A maximum of 23 g.L-1 PHB was extracted in 40 min run with 50 passes and 0.10 cavitation number at 3.9 bar pressure. The extracted biopolymer was characterized and was found to be PHB. Comparative analysis shows that HC results in a substantial reduction in the downstream processing time. Moreover, it has double the efficiency of PHB extraction as compared to the distilled water lysis method. This paper reports the HC process as a technocommercial alternative to industrial PHB extraction. [ABSTRACT FROM AUTHOR]

In the wake of escalating global concerns over the environmental impact of plastic pollution, there has been an unprecedented call for sustainable alternatives. The food-packaging industry, responsible for a staggering 40% of global plastic consumption, faces mounting challenges driven by environmental degradation and concerns about fossil fuel depletion. Motivated by these challenges, there is a growing interest in reducing reliance on traditional packaging and exploring eco-friendly solutions derived from renewable resources. Eco-efficient packaging, specifically derived from agricultural raw materials, emerges as a promising solution that aligns with ecological, economic, and social sustainability principles. Starch, abundant and versatile, emerges as a frontrunner among agricultural raw materials for biopolymers. Its inherent properties, including low cost, availability, biodegradability, and biocompatibility, make it a compelling choice. Starch-based bioplastics, with their potential to replace synthetic primary packaging materials, have gained traction due to their satisfactory mechanical and barrier properties. This review delves into the realm of starch-based films and coatings for food applications. It explores fundamental properties, advantages, and limitations, offering insights into potential improvements through various treatments or additive combinations. As technological advances drive the popularity of biodegradable starch-based packaging, this review aims to contribute to the ongoing discourse, providing a comprehensive overview and paving the way for more functional and widely applicable products in the ever-evolving landscape of sustainable packaging. [ABSTRACT FROM AUTHOR]

Biodegradable polymer nanocomposites (BPNCs) are advanced materials that have gained significant attention over the past 20 years due to their advantages over conventional polymers. BPNCs are eco-friendly, cost-effective, contamination-resistant, and tailorable for specific applications. Nevertheless, their usage is limited due to their unsatisfactory physical and mechanical properties. To improve these properties, nanofillers are incorporated into natural polymer matrices, to enhance mechanical durability, biodegradability, electrical conductivity, dielectric, and thermal properties. Despite the significant advances in the development of BPNCs over the last decades, our understanding of their dielectric, thermal, and electrical conductivity is still far from complete. This review paper aims to provide comprehensive insights into the fundamental principles behind these properties, the main synthesis, and characterization methods, and their functionality and performance. Moreover, the role of nanofillers in strength, permeability, thermal stability, biodegradability, heat transport, and electrical conductivity is discussed. Additionally, the paper explores the applications, challenges, and opportunities of BPNCs for electronic devices, thermal management, and food packaging. Finally, this paper highlights the benefits of BPNCs as biodegradable and biodecomposable functional materials to replace traditional plastics. Finally, the contemporary industrial advances based on an overview of the main stakeholders and recently commercialized products are addressed. [ABSTRACT FROM AUTHOR]

Textile production is a major component of the global industry, with sales of over USD 450 billion and estimations of an 84% increase in their demand in the next 20 years. In recent decades, protective and smart textiles have played important roles in the social economy and attracted widespread popularity thanks to their wide spectrum of applications with properties, such as antimicrobial, water-repellent, UV, chemical, and thermal protection. Towards the sustainable manufacturing of smart textiles, biodegradable, recycled, and bio-based plastics are used as alternative raw materials for fabric and yarn production using a wide variety of techniques. While conventional techniques present several drawbacks, nanofibers produced through electrospinning have superior structural properties. Electrospinning is an innovative method for fiber production based on the use of electrostatic force to create charged threads of polymer solutions. Electrospinning shows great potential since it provides control of the size, porosity, and mechanical resistance of the fibers. This review summarizes the advances in the rapidly evolving field of the production of nanofibers for application in smart and protective textiles using electrospinning and environmentally friendly polymers as raw materials, and provides research directions for optimized smart fibers in the future. [ABSTRACT FROM AUTHOR]

Measures to endorse the adoption of eco-friendly biodegradable plastics as a response to the scale of plastic pollution has created a demand for innovative products from materials from Nature. Ionic liquids (ILs) have the ability to disrupt the hydrogen bonding network of biopolymers, increase the mobility of biopolymer chains, reduce friction, and produce materials with various morphologies and mechanical properties. Due to these qualities, ILs are considered ideal for plasticizing biopolymers, enabling them to meet a wide range of specifications for biopolymeric materials. This mini-review discusses the effect of different IL-plasticizers on the processing, tensile strength, and elasticity of materials made from various biopolymers (e.g., starch, chitosan, alginate, cellulose), and specifically covers IL-plasticized packaging materials and materials for biomedical and electrochemical applications. Furthermore, challenges (cost, scale, and eco-friendliness) and future research directions in IL-based plasticizers for biopolymers are discussed. [ABSTRACT FROM AUTHOR]

Recent advances in the fabrication of neuromorphic electronic devices using biomaterials have received increasing attention for their prospect in biologically compatible and "green" electronic devices. Here, we proposed a novel electric-double-layer (EDL) synaptic transistor gated with Li-doped natural gelatin membranes, demonstrating larger capacitance at low frequency and extremely strong electrostatic modulation behavior. Experimental results have shown that a concentration of 2 wt. % Li-doping can obtain better electrical performance of EDL synaptic transistor. Ion/Ioff of 4.86 × 105 and threshold voltage of 0.68 V were obtained. Meanwhile, some important synaptic functions such as excitatory postsynaptic current, paired-pulse facilitation, and high-pass filtering characteristic have been successfully implemented. As a result, it can be inferred that the proposed gelatin-based natural polymer EDL electrolyte has demonstrated potential applications in "green" neuromorphic platforms. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop a bioplastic based on hydroxyethylcellulose (HEC) and polyvinilpyrrolidone (PVP) which is applied as packaging materials. The effect of incorporation of PVP into HEC on the physicochemical properties of its blend films are investigated. The FTIR and DSC analysis denote that incorporation of PVP induce the intermolecular hydrogen bonds to occur more intensely. The XRD diffractograms indicate that the incorporation of PVP reduces the crystallinity of the film. The mechanical properties of the films become greater as the PVP content increases, and the optimum composition of HEC/PVP is at 5:3 mass ratio with a tensile strength of 34.8±3.4 MPa; elongation at break 104.3±4.9 %; and an elastic modulus of 0.10±0.02 GPa. The SEM and DSC analysis signify an excellent compatibility and miscibility between HEC and PVP. The incorporation of PVP increase the transparency and hydrophilicity of the film. The water vapor transmission rate of the films is relatively unchanged due to the incorporation of PVP. The TGA and DSC analysis reveal that the incorporation of PVP increases the thermal stability and the glass transition temperature of the film. This bioplastic film could be an alternative for biodegradable packaging material. [ABSTRACT FROM AUTHOR]

Polymers are ideal solutions for architects and constructors in the marine field who require materials that can achieve light and stable structures owing to their unique advantages. For instance, they possess a high strength-to-weight ratio, high wear resistance and fatigue strength, resistance to corrosion, ease of fabrication, and superior vibration damping behavior. These properties make polymers well suited for marine-based applications. However, polymers have their disadvantages, such as contributing to plastic pollution, which has a detrimental impact on the environment. In recent times, various concurrent methods have been employed to advance the future of polymers. This review explores (i) an overall view of polymers used in marine industries, (ii) a focus on reducing plastic wastage, (iii) challenges involved in recycling polymers and ensuring their sustainability, and (iv) the development of renewable plastics. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHA), due to their remarkable biodegradability, biocompatibility, and favorable physical and chemical properties, are tested for applications in the agricultural, industrial, and medical fields in place of conventional plastic. Sustainable microbial PHA production is a challenge because of the economic aspects accrued due to the cost-effective substrates and downstream processing. Different approaches are adopted to circumvent the high economic price of PHA production by co-production, employing recombinant strain, mixed cultures, and low-cost feedstock. The review focuses on the co-production of intracellular microbial PHA with an extracellular value-added product. The present review highlights the feasibility of other bio-based products from the feedstock to offset the cost of PHA production with emphasis on another viable option. The paper discusses the recent progress in the simultaneous production of PHA with exopolysaccharides, pigments, enzymes, bio-surfactants, biofuels which primarily fulfill the criteria of higher yield of PHA, and another high-value product that can be achieved. This approach not only maximizes resource utilization but also provides opportunities for the development of a wide range of sustainable bio-based products to improve the overall feasibility of the process. [ABSTRACT FROM AUTHOR]

Sustainable packaging has been steadily gaining prominence within the food industry, with biobased materials emerging as a promising substitute for conventional petroleum-derived plastics. This review is dedicated to the examination of innovative biobased materials in the context of bread packaging. It aims to furnish a comprehensive survey of recent discoveries, fundamental properties, and potential applications. Commencing with an examination of the challenges posed by various bread types and the imperative of extending shelf life, the review underscores the beneficial role of biopolymers as internal coatings or external layers in preserving product freshness while upholding structural integrity. Furthermore, the introduction of biocomposites, resulting from the amalgamation of biopolymers with active biomolecules, fortifies barrier properties, thus shielding bread from moisture, oxygen, and external influences. The review also addresses the associated challenges and opportunities in utilizing biobased materials for bread packaging, accentuating the ongoing requirement for research and innovation to create advanced materials that ensure product integrity while diminishing the environmental footprint. [ABSTRACT FROM AUTHOR]

This review presents a comprehensive update of the biopolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), emphasizing its production, properties, and applications. The overall biosynthesis pathway of PHBV is explored in detail, highlighting recent advances in production techniques. The inherent physicochemical properties of PHBV, along with its degradation behavior, are discussed in detail. This review also explores various blends and composites of PHBV, demonstrating their potential for a range of applications. Finally, the versatility of PHBV-based materials in multiple sectors is examined, emphasizing their increasing importance in the field of biodegradable polymers. [ABSTRACT FROM AUTHOR]

The use of natural polymers has increased due to concern about environmental pollution caused by plastics and emerging pollutants from fossil fuels. In this context, polysaccharides from macroalgae and microalgae arise as natural and abundant resources for various biological, biomedical, and food applications. Different nanomaterials are produced from these polysaccharides to act as effective carriers in the food and pharmaceutical industry: drug and nutrient carriers, active compound encapsulation, and delivery of therapeutic agents to tumor tissues. Polysaccharides-based nanomaterials applied as functional ingredients incorporated into foods can improve texture properties and decrease the caloric density of food products. These nanostructures also present the potential for developing food packaging with antioxidant and antimicrobial properties. In addition, polysaccharides-based nanomaterials are biocompatible, biodegradable, and safe for medical practices to prevent and manage various chronic diseases, such as diabetes, obesity, and cardiovascular disease. In this sense, this review article addresses the use of algal polysaccharides for manufacturing nanomaterials and their potential applications in food and biomedical areas. In addition, the paper discusses the general aspects of algae as a source of polysaccharides, the nanomaterials produced from these polymers, as well as recent studies and the potential use of algal polysaccharides for industries. [ABSTRACT FROM AUTHOR]

The present work is a review of the research on using hydrogels based on natural biodegradable polymers, starch, and gelatin for enzyme immobilization. This review addresses the main properties of starch and gelatin that make them promising materials in biotechnology for producing enzyme preparations stable during use and storage and insensitive to chemical and physical impacts. The authors summarize their achievements in developing the preparations of enzymes immobilized in starch and gelatin gels and assess their activity, stability, and sensitivity for use as biorecognition elements of enzyme inhibition-based biosensors. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHAs) are biodegradable polymers with immense potential in addressing the global plastic pollution crisis and advancing sustainable bioplastics production. Among the various microbes known for PHA production, extremophilic bacteria possess unique capabilities to thrive under extreme conditions, making them attractive candidates for PHA synthesis. Furthermore, the utilization of renewable feedstocks for PHA production aligns with the growing demand for sustainable bioplastic alternatives. A diverse range of extremophilic bacteria, especially halophiles and thermophiles, has provided cost-competitive platforms for producing customized PHA polymers. Extremophilic bacteria offer unique advantages over mesophiles due to their contamination resistance, high cell density growth, and unique culture conditions. The current status of Halomonas spp. as a chassis further allows exploration of metabolic engineering approaches to overcome the challenges associated with current industrial biotechnology. This article especially focuses on extremophilic bacteria and explores recent advances in utilizing renewable feedstocks such as lignocellulosic biomass, agro-industrial residues, and waste streams for PHA production. The integration of biorefinery concepts and circular economy principles in PHA manufacturing is also examined. This review is an attempt to provide an understanding of renewable substrates as feedstocks and emerging trends in PHA production by extremophilic bacteria. It underscores the pivotal role of extremophiles and sustainable feedstock sources in advancing the feasibility and eco-friendliness of PHAs as a promising biopolymer alternative. [ABSTRACT FROM AUTHOR]

Quantification and characterization of microplastics, synthetic polymers less than 5 mm in diameter, requires extraction methods that can reduce non-plastic debris without loss or alteration of the polymers. Nitric acid has been used to extract plastic particles from zooplankton and other biota because it completely digests tissue and exoskeletons, thus reducing interferences. While the impact of acid digestion protocols on several polymers has been demonstrated, advice for quantifying microplastic and interpreting their spectra following nitric acid digestion is lacking. Fourier transform infrared (FTIR) and/or Raman spectroscopy was performed on plastics from > 50 common consumer products (including a variety of textiles) pre- and post-nitric acid treatment. The percent match and assigned polymer were tabulated to compare the accuracy of spectral identification before and after nitric acid digestion via two open spectral analysis software. Nylon-66, polyoxymethylene, polyurethane, polyisoprene, nitrile rubber, and polymethyl methacrylate had ≥ 90% mass loss in nitric acid. Other less-impacted polymers changed color, morphology, and/or size following digestion. Thus, using nitric acid digestion for microplastic extraction can impact our understanding of the particle sizes and morphologies ingested in situ. Spectral analysis results were compiled to understand how often (1) the best-hit matches were correct (30–60% of spectra), (2) the best-hit matches exceeding the (arbitrary) threshold of 65% match were correct (53–78% of spectra), and (3) the best-hit matches for anthropogenic polymers were incorrectly identified as natural polymers (12–15% of spectra). Based on these results, advice is provided on how nitric acid digestion can impact microplastics as well as spectral interpretation. [ABSTRACT FROM AUTHOR]

It is undeniable that suitable packaging will extend the shelf life of the food. The packaging industry has had to renew and innovate in a world where consumers are increasingly environmentally conscious in order to deal with the impact of the production of petroleum-derived plastics and the management of the waste generated by them. In this way, the use of biopolymers has been proposed, mainly those produced from renewable sources and with biodegradability and/or compostability properties. However, these types of materials are more expensive and do not have the same performance as petroleum-derived materials. Besides, the technologies for film preparation are not adapted for these materials. Therefore, new technologies must be studied and implemented to make the packaging industry a sustainable industry. Recently, non-solvent phase inversion (NIPS) and electrospinning techniques, which are widely used for membrane fabrication, have been proposed for the fabrication of films for food packaging applications from biopolymers and green solvents. [ABSTRACT FROM AUTHOR]

Microbial communities perform essential ecosystem functions such as the remineralization of organic carbon that exists as biopolymers. The first step in mineralization is performed by biopolymer degraders, which harbor enzymes that can break down polymers into constituent oligo- or monomeric forms. The released nutrients not only allow degraders to grow, but also promote growth of cells that either consume the degradation products, i.e., exploiters, or consume metabolites released by the degraders or exploiters, i.e., scavengers. It is currently not clear how such remineralizing communities assemble at the microscale--how interactions between the different guilds influence their growth and spatial distribution, and hence the development and dynamics of the community. Here, we address this knowledge gap by studying marine microbial communities that grow on the abundant marine biopolymer alginate. We used batch growth assays and microfluidics coupled to time-lapse microscopy to quantitatively investigate growth and spatial distribution of single cells. We found that the presence of exploiters or scavengers alters the spatial distribution of degrader cells. In general, exploiters and scavengers--which we collectively refer to as cross-feeder cells--slowed down the growth of degrader cells. In addition, coexistence with cross-feeders altered the production of the extracellular enzymes that break down polymers by degrader cells. Our findings reveal that ecological interactions by nondegrading community members have a profound impact on the functions of microbial communities that remineralize carbon biopolymers in nature. [ABSTRACT FROM AUTHOR]

The widespread use of synthetic plastics, as well as the waste produced at the end of their life cycle, poses serious environmental issues. In this context, bio-based plastics, i.e., natural polymers produced from renewable resources, represent a promising alternative to petroleum-based materials. One potential source of biopolymers is waste from the food industry, the use of which also provides a sustainable and eco-friendly solution to waste management. Thus, the aim of this work concerns the extraction of polysaccharide fractions from lemon, tomato and fennel waste. Characterizing the chemical–physical and thermodynamic properties of these polysaccharides is an essential step in evaluating their potential applications. Hence, the solubility of the extracted polysaccharides in different solvents, including water and organic solvents, was determined since it is an important parameter that determines their properties and applications. Also, acid-base titration was carried out, along with thermoanalytical tests through differential scanning calorimetry. Finally, the electrospinning of waste polysaccharides was investigated to explore the feasibility of obtaining polysaccharide-based membranes. Indeed, electrospun fibers are a promising structure/system via which it is possible to apply waste polysaccharides in packaging or well-being applications. Thanks to processing feasibility, it is possible to electrospin waste polysaccharides by combining them with different materials to obtain porous 3D membranes made of nanosized fibers. [ABSTRACT FROM AUTHOR]

Ulvan is a sulfated polysaccharide extracted from green macroalgae with unique structural and compositional properties. Due to its biocompatibility, biodegradability, and film-forming properties, as well as high stability, ulvan has shown promising potential as an ingredient of biopolymer films such as sustainable and readily biodegradable biomaterials that could replace petroleum-based plastics in diverse applications such as packaging. This work investigates the potential of Ulva fenestrata as a source of ulvan. Enzyme-assisted extraction with commercial cellulases (Viscozyme L and Cellulysin) and proteases (Neutrase 0.8L and Flavourzyme) was used for cell wall disruption, and the effect of the extraction time (3, 6, 17, and 20 h) on the ulvan yield and its main characteristics (molecular weight, functional groups, purity, and antioxidant capacity) were investigated. Furthermore, a combined process based on enzymatic and ultrasound extraction was performed. Results showed that higher extraction times led to higher ulvan yields, reaching a maximum of 14.1% dw with Cellulysin after 20 h. The combination of enzymatic and ultrasound-assisted extraction resulted in the highest ulvan extraction (17.9% dw). The relatively high protein content in U. fenestrata (19.8% dw) makes the residual biomass, after ulvan extraction, a potential protein source in food and feed applications. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) is one of the most commonly used bioplastics thanks to its mechanical performance and low environmental impact. Strategies to overcome excessive rigidity of PLA are constantly investigated. Poor viscoelastic behavior and brittleness of PLA seriously limit its potential application as a common film material. Herein highly amorphous Poly(3-hydroxybutyrate-4-hydroxybutyrate) (P(3HB)(4HB)) was introduced to improve toughness and reduce brittleness of PLA. Anti-blocking (silica) and anti-slipping agent (Ethylene bis-stearamide (EBS)) were added to improve the processability of the blends, specifically to solve winding issues of the blown film and unfolding of the layflat. In this study three formulations containing PLA and different ratios of P(3HB)(4HB), specifically 10-20-30% were extruded. The mechanical, thermal and surface characterization of the films was performed. The tensile and the tear strength test results show that P(3HB)(4HB) increased the ductility of PLA based films. Increasing amounts of P(3HB)(4HB) provide a toughening effect on PLA/P(3HB)(4HB) blown films without altering transparency of PLA. Moreover, the processing additives proved to be efficient in improving film blowing stability and avoiding tackiness during the winding phase of the film. [ABSTRACT FROM AUTHOR]

In light of the growing concern for environmental protection and the alarming amount of waste produced due to hygiene regulations, this study suggests a biodegradable and eco-friendly solution that could make a significant contribution to the preservation of our planet. The developed solution was based on a polyhydroxybutyrate/polyhydroxyvalerate biopolymer, which has been tested regarding its physicochemical parameters and possible use in printed electrically conductive structures. Graphene nanoplatelets have been used as the conductive functional phase, due to literature reports of their potential use in biomedical applications and due to the potential of providing cytocompatibility in electrical structures by carbon nanomaterials. Prepared composites have been spray-coated onto PET film and paper substrates and then subjected to electrical, adhesion and optical measurements. In order to establish the conductivity of the developed composite, its resistance, layer thickness and surface topography were measured. Optical parameters have been specified using scanning electron microscopy (SEM) imaging and spectrophotometry. The conducted research opens a wide path for the use of the polyhydroxybutyrate/polyhydroxyvalerate biopolymer with graphene nanoplatelets in biomedical applications, ensuring good conductivity, biocompatibility and stability. [ABSTRACT FROM AUTHOR]

Several solutions have been presented to minimize the environmental impact generated by polymers produced from petroleum resources. This work produced a biopolymer using glycerol, starch (<5) and macaúba epicarp fiber (10–15–20–25–30%) as reinforcement. The interaction of glycerol with starch was favored by the addition of acetic acid (CH3COOH). The pH was adjusted with sodium hydroxide (NaOH) at a concentration of 0.1 mol·L−1. The characterization was carried out through scanning electron microscopy (SEM), infrared reflectance—FTIR, water solubility, biodegradability and technological properties. Through the results obtained in this work, it is observed that the tensile strength and modulus of elasticity are influenced by the addition of the fiber concentration; the sample that received a 30% addition presented 19.17 MPa and 348.12 MPa, respectively. All samples showed low solubility in water and low density, in addition to a high rate of degradability in soil with mass loss corresponding to 59% over a period of three months. The results of this investigation are satisfactory for the production of materials that can be used in everyday life, replacing conventional plastic. [ABSTRACT FROM AUTHOR]

In recent years, plastics recycling has become one of the leading environmental and waste management issues. Along with the main advantage of plastics, which is undoubtedly their long life, the problem of managing their waste has arisen. Recycling is recognised as the preferred option for waste management, with the aim of reusing them to create new products using 3D printing. Additive manufacturing (AM) is an emerging and evolving rapid tooling technology. With 3D printing, it is possible to achieve lightweight structures with high dimensional accuracy and reduce manufacturing costs for non-standard geometries. Currently, 3D printing research is moving towards the production of materials not only of pure polymers but also their composites. Bioplastics, especially those that are biodegradable and compostable, have emerged as an alternative for human development. This article provides a brief overview of the possibilities of using thermoplastic waste materials through the application of 3D printing, creating innovative materials from recycled and naturally derived materials, i.e., biomass (natural reinforcing fibres) in 3D printing. The materials produced from them are ecological, widely available and cost-effective. Research activities related to the production of bio-based materials have gradually increased over the last two decades, with the aim of reducing environmental problems. This article summarises the efforts made by researchers to discover new innovative materials for 3D printing. [ABSTRACT FROM AUTHOR]

Chitosan is a natural biodegradable polymer that is recovered from marine shell wastes. It has been widely employed in anticancer, antioxidant, and antibacterial applications due to its outstanding qualities, including biological compatibility, muco-adhesivity, hemocompatibility, and biodegradability. The contributions of this polymer have established it with respect to biomedical applications. The distinct morphologies of chitosan, such as in nanoparticulate and microparticulate for MS and as derivatives and composites have extended its visages even beyond biomedicine. This review specifically summarizes the biomedical highlights of chitosan-based MS. Special attention has been focused on the antimicrobial accomplishments of chitosan-based MS. The impact of chitosan MS against bacteria, fungi and viruses has been reviewed. The gaps in its usage for antimicrobial investigations have been addressed. The lack of significant contribution from chitosan MS towards antifungal and antiviral applications has been explicitly highlighted. Future recommendations and the scope for expansion have been suggested. [ABSTRACT FROM AUTHOR]

Background: Polyhydroxybutyrate (PHB) is currently the most common polymer produced by natural bacteria and alternative to conventional petrochemical-based plastics due to its similar material properties and biodegradability. Massilia sp. UMI-21, a newly found bacterium, could produce PHB from starch, maltotriose, or maltose, etc. and could serve as a candidate for seaweed-degrading bioplastic producers. However, the genes involved in PHB metabolism in Massilia sp. UMI-21 are still unclear. Results: In the present study, we assembled and annotated the genome of Massilia sp. UMI-21, identified genes related to the metabolism of PHB, and successfully constructed recombinant Escherichia coli harboring PHB-related genes (phaA2, phaB1 and phaC1) of Massilia sp. UMI-21, which showed up to 139.41% more product. Also, the vgb gene (encoding Vitreoscilla hemoglobin) was introduced into the genetically engineered E. coli and gained up to 117.42% more cell dry weight, 213.30% more PHB-like production and 44.09% more product content. Fermentation products extracted from recombinant E. coli harboring pETDuet1-phaA2phaB1-phaC1 and pETDuet1-phaA2phaB1-phaC1-vgb were identified as PHB by Fourier Transform Infrared and Proton nuclear magnetic resonance spectroscopy analysis. Furthermore, the decomposition temperature at 10% weight loss of PHB extracted from Massilia sp. UMI-21, recombinant E. coli DH5α-pETDuet1-phaA2phaB1-phaC1 and DH5α-pETDuet1-phaA2phaB1-phaC1-vgb was 276.5, 278.7 and 286.3 °C, respectively, showing good thermal stability. Conclusions: Herein, we presented the whole genome information of PHB-producing Massilia sp. UMI-21 and constructed novel recombinant strains using key genes in PHB synthesis of strain UMI-21 and the vgb gene. This genetically engineered E. coli strain can serve as an effective novel candidate in E. coli cell factory for PHB production by the rapid cell growth and high PHB production. [ABSTRACT FROM AUTHOR]

Global pollution from fossil plastics is one of the top environmental threats of our time. At their end-of-life phase, fossil plastics, through recycling, incineration, and disposal result in microplastic formation, elevated atmospheric CO2 levels, and the pollution of terrestrial and aquatic environments. Current regional, national, and global regulations are centered around banning plastic production and use and/or increasing recycling while ignoring efforts to rapidly replace fossil plastics through the use of alternatives, including those that occur in nature. In particular, this review demonstrates how microbial polyhydroxyalkanoates (PHAs), a class of intrinsically natural polymers, can successfully remedy the fossil and persistent plastic dilemma. PHAs are bio-based, biosynthesized, biocompatible, and biodegradable, and thus, domestically and industrially compostable. Therefore, they are an ideal replacement for the fossil plastics pollution dilemma, providing us with the benefits of fossil plastics and meeting all the requirements of a truly circular economy. PHA biopolyesters are natural and green materials in all stages of their life cycle. This review elaborates how the production, consumption, and end-of-life profile of PHAs are embedded in the current and topical, 12 Principles of Green Chemistry, which constitute the basis for sustainable product manufacturing. The time is right for a paradigm shift in plastic manufacturing, use, and disposal. Humankind needs alternatives to fossil plastics, which, as recalcitrant xenobiotics, contribute to the increasing deterioration of our planet. Natural PHA biopolyesters represent that paradigm shift. [ABSTRACT FROM AUTHOR]

Wide applications of conventional plastics across the world have made its production inevitable. To avoid the ecocide occurring due to conventional plastics, studies on the production and extraction of renowned biopolymers like polyhydroxyalkanoates (PHAs) are explored. PHA is a family of polyesters naturally produced by bacterial fermentation with the potential to replace conventional hydrocarbon-based polymers. The efficient utilization of industrial discard as renewable feedstocks in the production of eco-friendly products such as bioplastics has been studied. This study focuses on the production of PHA using cashew industry wastewater (CIW). Since cashew industry wastewater (CIW) is rich in phenolic compounds and other sources, this study explores the possibility of eliminating the toxic phenol compounds from the waste by the production of PHA using cashew industry wastewater as a secondary source of carbon by paving the way to eco-friendly process. In this context, PHA-producing bacterium was isolated from wastewater samples collected from cashew industries. The morphological, microscopic, and biochemical characterization revealed that the isolated strain CFM1 is Bacillus sp. The strain CFM1 that gave maximum (30%) PHA in control medium was taken up for further studies with wastewater. The concentration of sucrose in the control production media was replaced with cashew industry wastewater. Wastewater was introduced to the medium at different concentrations (10–100%). As CIW concentration was increased, the sucrose concentration was decreased in the medium accordingly. CFM1 isolates produced 34% PHA with 20% wastewater. The biopolymer produced was characterized by FTIR and NMR. [ABSTRACT FROM AUTHOR]

Over the years, exopolysaccharides (EPSs) have been utilized in various areas of research, including health, industry, environment, and agriculture, due to their flexible physical, chemical and structural properties that can be readily modified to suit desired purposes. Current research trends have shown that EPS production is dependent on numerous factors which can be combined to varying extent to optimize production yields. Although the majority of research is directed towards their industrial and medicinal uses, these chemical substances possess peculiar characteristics which are also exploited for biomedical research, where they are being used as drug delivery systems, some of which include their abundance in nature, biocompatibility, biodegradability, non-toxicity, and ability to efficiently encapsulate sensitive bioactive agents. However, despite the numerous beneficial prospects of microbial EPSs in drug delivery, there are limitations to the commercial production and industrial applications of these biopolymers. These limitations have inspired revolutionary research into the cost-effective production of safe EPSs polymers. In this review, we classify EPSs and discuss their methods of extraction and characterization. We also summarized current drug delivery applications and discussed limitations to extensive industrial commercialization of EPSs, while highlighting prospects for the utilization of microbial EPSs and implications for research. [ABSTRACT FROM AUTHOR]