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The collective dynamics of active biopolymers is crucial for many processes in life, such as cellular motility, intracellular transport, and division. Recent experiments revealed fascinating self-organized patterns of diverse active filaments, while an explicit parameter control strategy remains an open problem. Moreover, theoretical studies so far mostly dealt with active chains with uniform stiffness, which are inadequate in describing the more complicated class of polymers with varying stiffness along the backbone. Here, using Langevin dynamics simulations, we investigate the collective behavior of active chains with homogeneous and heterogeneous stiffness in a comparative manner. We map a detailed non-equilibrium phase diagram in activity and stiffness parameter space. A wide range of phase states, including melt, cluster, spiral, polar, and vortex, are demonstrated. The appropriate parameter combination for large-scale polar and vortex formation is identified. In addition, we find that stiffness heterogeneity can substantially modulate the phase behaviors of the system. It has an evident destructive effect on the long-ranged polar structure but benefits the stability of the vortex pattern. Intriguingly, we unravel a novel polar–vortex transition in both homogeneous and heterogeneous systems, which is closely related to the local alignment mechanism. Overall, we achieve new insights into how the interplay among activity, stiffness, and heterogeneity affects the collective dynamics of active filament systems. [ABSTRACT FROM AUTHOR]

Organic matter can initiate heterogeneous ice nucleation in supercooled water droplets, thereby influencing atmospheric cloud glaciation. Predicting the ice nucleation ability of organic matter-containing cloud droplets is challenging due to the unknown mechanism for templating ice. Here, we observed the presence of nanoparticles in aqueous samples of known ice-nucleating biopolymers cellulose and lignin, as well as in newly identified ice-nucleating biopolymers xylan and laminarin. Using our drop Freezing Ice Nuclei Counter (FINC), we measured the median ice nucleation temperature (T50) of xylan and of laminarin droplets of 2 μl to be −14.2 and −20.0 °C, respectively. Next, we characterized these samples using nanoparticle tracking analysis, and we detected and quantified nanoparticles with mean diameters between 132 and 267 nm. Xylan contained the largest nanoparticles and froze at higher temperatures. Xylan also dictated the freezing in a 1:1:1:1 mixture with cellulose, lignin, laminarin, and xylan. Filtration experiments down to 300 kDa with the xylan sample indicated that the presence of nanoparticles triggered freezing. Overall, only samples with mean diameters above 150 nm froze above −20 °C. Furthermore, we determined the ice-active site densities normalized to particle concentrations, surface area, and mass of the nanoparticles to show that the samples' nucleation site densities are similar to sea spray aerosols and nanometer-sized dust. The identification and characterization of xylan and laminarin as nanometer-sized ice-nucleating substances expands the growing list of organic matter capable of impacting cloud formation and thus climate. [ABSTRACT FROM AUTHOR]

Excessive ultraviolet (UV) radiation can cause human skin erythema, tanning, inflammation and other adverse reactions. Human skin can spontaneously synthesize endogenous melanin under UV radiation to defend against the damage of UV, but skin problems such as light damage and light aging cannot be avoided due to its low UV shielding efficiency. Therefore, we design a natural and biocompatible PGDA (poly-γ-glutamic acid/melanin-like hydrogel) sunscreen hydrogel by crosslinking melanin-like L -lysine-doped polydopamine (PDA- L) and amino acid biopolymer poly-γ-glutamic acid, which displays good biosafety, efficient UVA shielding performance and excellent anti-inflammatory performance in the applications of skin protection from the sun and repair after sunburn. The introduction of PDA- L to the hydrogel can improve the absorption intensity in the UV region and the antioxidative performance of the hydrogel. Meanwhile, the usage of biocompatible PGDA sunscreen hydrogel can avoid the skin oxidative damage and penetrative toxicity of conventional sunscreens. [ABSTRACT FROM AUTHOR]

The escalating worldwide apprehension over environmental deterioration caused by plastic pollution owing to the detrimental effects of conventional plastics has eventually led to the orientation towards biopolymer-based sustainable packaging materials. Contemporary food industries encounter a multitude of challenges to meet consumer demand of upholding food quality and implementing extended preservation strategies. This has in turn compelled the researchers to emphasize the development of multifunctional sustainable packaging materials. Biopolymers can serve as a sustainable alternative to conventional plastics, but they lack certain properties when compared to conventional plastics. The incorporation of different nanomaterials derived through organic or inorganic sources has been demonstrated to impart different properties to the resultant biocomposite films. The nanobiocomposite materials which serve as a union of nanotechnology, biodegradability, and sustainability have further paved the way for advanced packaging which offers added functionalities like enhanced mechanical strength, barrier properties, antimicrobial activity, antioxidant properties and real time monitoring of food quality. Furthermore, it discusses the potential risks associated with nanomaterial utilization. In addition, the study also emphasizes the need for continued advancements and research in nanobiocomposite film technology as ways to tackle the challenges of food preservation, waste management, a sustainable future, and consumer health. [ABSTRACT FROM AUTHOR]

To promote the formation of granular sludge with high polyhydroxyalkanoates (PHAs) synthesis ability, an anaerobic dynamic feeding process (AnDF) was proposed. This process combines the feast-famine mode with an anaerobic plug flow feeding process and involving variations in cycle length and settling time. The effects of lactic acid (LA) content (0 %, 20 %, and 40 % COD) on sludge granulation and PHAs production were investigated using three AnDF reactors (R1, R2, and R3). The results showed that the AnDF process feeding with LA not only effectively promoted sludge granulation but also improved its PHAs synthesis ability. The granules were quickly observed in R3 after 50 days of cultivation, with an average diameter of 0.69 mm. The maximum PHAs content reached 47.0 wt% in R3, representing a 30.09 % increase compared to R1. Additionally, extracellular polymeric substances (EPS)-producing bacteria observed in granular sludge may be the prime drivers of the formation of PHAs-producing granular sludge (PHAGS), which was defined as granular sludge with an average particle size larger than 0.30 mm and PHAs content above 40 % cell dry weight (CDW) of sludge samples. [Display omitted] • The concept of PHAs-producing granular sludge (PHAGS) was proposed. • Lactic acid feeding is benefit for sludge granulation and PHAs synthesis. • The rapid PHAGS formation was obtained by anaerobic dynamic feeding process. • The formation of PHAGS may be related to the enriched EPS-producing bacteria. [ABSTRACT FROM AUTHOR]

This study evaluated the influence of adding borosilicate residue (BS) as a flame retardant in polypropylene (PP) and natural fiber composites. The natural fibers used in this study come from the residue of the carpet industry, which is composed of PP and jute fibers (JT), while the PP used as the polymer matrix is postindustrial recycled material. The composites were produced by corotational twin‐screw extrusion and injection molding to obtain the test specimens. A coating process was carried out to add the water‐soluble fraction of BS to the surface of the compositions that did not receive it through incorporation during processing. To characterize the composites, flammability tests, thermogravimetric analysis (TGA), tensile strength test, and morphological analysis by scanning electron microscope (SEM) were performed. The addition of only 2 wt% BS content induces an increase in thermal stability of 32 and 109°C for composites with and without natural fibers, respectively. The addiction of 20 wt% BS elevates the elastic modulus up to 27% of the composites with and without natural fibers. The BS characterization indicates that it could be applied as a flame retardant when applied as coating methods using the water‐soluble fraction of BS, reducing the burning rate up to 92%. Flammability results are similar for formulations with and without natural fibers, indicating that the natural fibers did not influence the proposed flame retardant. The findings suggest that BS coating is a potential solution to improve the properties of natural fiber‐reinforced polymer composites while also promoting waste recycling. This approach produces composites with improved flammability, thermal stability, and mechanical properties, making them suitable for various end applications. [ABSTRACT FROM AUTHOR]

Plants started to colonize land around 500 million years ago. It meant dealing with new challenges like absence of buoyancy, water and nutrients shortage, increased light radiation, reproduction on land, and interaction with new microorganisms. This obviously required the acquisition of novel functions and metabolic capacities. Cytochrome P450 (CYP) monooxygenases form the largest superfamily of enzymes and are present to catalyse critical and rate-limiting steps in most plant-specific pathways. The different families of CYP enzymes are typically associated with specific functions. CYP family emergence and evolution in the green lineage thus offer the opportunity to obtain a glimpse into the timing of the evolution of the critical functions that were required (or became dispensable) for the plant transition to land. Based on the analysis of currently available genomic data, this review provides an evolutionary history of plant CYPs in the context of plant terrestrialization and describes the associated functions in the different lineages. Without surprise it highlights the relevance of the biosynthesis of antioxidants and UV screens, biopolymers, and critical signalling pathways. It also points to important unsolved questions that would deserve to be answered to improve our understanding of plant adaptation to challenging environments and the management of agricultural traits. This article is part of the theme issue 'The evolution of plant metabolism'. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) granules are frequently used in orthopedics and maxillofacial surgeries to fill bone defects and stimulate the regeneration process. Optimal HA granules should have high biocompatibility, high microporosity and/or mesoporosity, and high specific surface area (SSA), which are essential for their bioabsorbability, high bioactivity (ability to form apatite layer on their surfaces) and good osseointegration with the host tissue. Commercially available HA granules that are sintered at high temperatures (≥ 900 °C) are biocompatible but show low porosity and SSA (2–5 m2/g), reduced bioactivity, poor solubility and thereby, low bioabsorbability. HA granules of high microporosity and SSA can be produced by applying low sintering temperatures (below 900 °C). Nevertheless, although HA sintered at low temperatures shows significantly higher SSA (10–60 m2/g) and improved bioabsorbability, it also exhibits high ion reactivity and cytotoxicity under in vitro conditions. The latter is due to the presence of reaction by-products. Thus, the aim of this study was to fabricate novel biomaterials in the form of granules, composed of hydroxyapatite nanopowder sintered at a high temperature (1100 °C) and a biopolymer matrix: chitosan/agarose or chitosan/β-1,3-glucan (curdlan). It was hypothesized that appropriately selected ingredients would ensure high biocompatibility and microstructural properties comparable to HA sintered at low temperatures. Synthesized granules were subjected to the evaluation of their biological, microstructural, physicochemical, and mechanical properties. The obtained results showed that the developed nanocomposite granules were characterized by a lack of cytotoxicity towards both mouse preosteoblasts and normal human fetal osteoblasts, and supported cell adhesion to their surface. Moreover, produced biomaterials had the ability to induce precipitation of apatite crystals after immersion in simulated body fluid, which, combined with high biocompatibility, should ensure good osseointegration after implantation. Additionally, nanocomposite granules possessed microstructural parameters similar to HA sintered at a low temperature (porosity approx. 50%, SSA approx. 30 m²/g), Young's modulus (5–8 GPa) comparable to cancellous bone, and high fluid absorption capacity. Moreover, the nanocomposites were prone to biodegradation under the influence of enzymatic solution and in an acidic environment. Additionally, it was noted that the hydroxyapatite nanoparticles remaining after the physicochemical dissolution of the biomaterial were easily phagocytosed by mouse macrophages, mouse preosteoblasts, and normal human fetal osteoblasts (in vitro studies). The obtained materials show great potential as bone tissue implantation biomaterials with improved bioresorbability. The obtained materials show great potential as bone tissue implantation biomaterials with improved bioresorbability. [ABSTRACT FROM AUTHOR]

[Display omitted] With the rapid development of the global economy and the continuous consumption of fossil resources, sustainable and biodegradable natural biomass has garnered extensive attention as a promising substitute for synthetic polymers. Due to their hierarchical and nanoscale structures, natural biopolymers exhibit remarkable mechanical properties, along with excellent innate biocompatibility and biodegradability, demonstrating significant potential in various application scenarios. Among these biopolymers, proteins and polysaccharides are the most commonly studied due to their low cost, abundance, and ease of use. However, the direct processing/conversion of proteins and polysaccharides into their final products has been a long-standing challenge due to their natural morphology and compositions. In this review, we emphasize the importance of processing natural biopolymers into high-value-added products through sustainable and cost-effective methods. We begin with the extraction of four types of natural biopolymers: cellulose, chitosan, eggshell membrane, and silk fibroin. The processing and post-functionalization strategies for these natural biopolymers are then highlighted. Alongside their unique structures, the versatile potential applications of these processable natural biopolymers in biomedical engineering, biosensors, environmental engineering, and energy applications are illustrated. Finally, we provide a summary and future outlook on processable natural biopolymers, underscoring the significance of converting natural biopolymers into valuable biomaterial platforms. [ABSTRACT FROM AUTHOR]

This research investigates the rheological behavior of the Poloxamer–chitosan thermogel system for the release of doxorubicin, which is a chemotherapy agent. To design the experiment, the response surface method was used to optimize the formula and investigate the mutual effects of the variables on the rheological properties of the system. In this experimental design, Poloxamer as a thermogel matrix (15–20%) and chitosan biopolymer as an additive (0.1–0.3%) were used and the pH of the test environment was determined in the range of 2.0–7.5. The results showed that the rheological behavior of the Poloxamer–chitosan combination has the best fit according to the Herschel–Bulkley model with a correlation coefficient of 100%. Also, adding chitosan to Poloxamer decreased the gelation temperature and gelation time. The results showed that the concentration of Poloxamer and chitosan as well as system temperature have a significant effect on the rheological behavior of thermogel. The optimized formula showed favorable rheological properties including high viscosity and appropriate degradation rate. The study showed the sustained release of the drug in the in vitro environment of the thermogel system during 144 h. The kinetics of the drug's release were also studied based on zero-order, first-order, Higuchi, and Korsmeyer–Peppas models. It was found that the Higuchi (R2 = 0.9888) and Korsmeyer–Peppas (R2 = 0.9851) models are the best models for the prediction of release kinetics of doxorubicin. Therefore, the design of the Poloxamer–chitosan thermogel system has the potential to be used as an in situ drug delivery system for doxorubicin. [ABSTRACT FROM AUTHOR]

The development of composite materials with fewer interface problems always helps to obtaining good properties. Two types of insulating biopolymers (7% w/w) were incorporated into a conductive matrix (polyaniline) during polymerization. The synthesis method, inspired by the synthesis of polyaniline and the coating of chitosan for the development of flexible electrodes, produces thermosets that are more thermally stable than the matrix until 350 °C. While one (gum) reduces the electrical conductivity, the other (lignin) increases the basic value of the raw material (~ 0.72 S Cm–1) by a factor of 10. The physicochemical and morphological analyses show the formation of the polymer on the surface of the biopolymer with the appearance of new chemical bonds by interactions between hydroxyls of the biopolymer and the nitrogen of amine function from the polyaniline. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose (BNC) currently has emerged as a potential biopolymer that can be used for various industrial applications. However, the major concern is the limitation of the bacteria used for BNC production on a larger scale. This study aimed to isolate and identify potential nanocellulose-producing bacteria from pineapple wastes. In this study, 11 isolates were screened and the F1 isolate, which produced the highest BNC yield was chosen for 16S rRNA sequencing. Based on the 16S rRNA analysis, Comamonas terrae YSZ sp. (OQ592726.1) was the best BNC producer with 1.68 ± 0.19 g/L yield. The physicochemical characteristics from FESEM analysis revealed that C. terrae YSZ sp. produced amorphous BNC, with fewer nanofibrils. The XRD analysis showed that the BNC produced had a 19.3% of crystallinity index. To the best of our knowledge, this is the first work reporting the isolation of C. terrae YSZ sp. from pineapple wastes with more amorphous regions providing an interesting alternative for heavy metal removal potentials. [ABSTRACT FROM AUTHOR]

In this study, two cardanol based epoxidized resins, NC514 with less than two epoxies per molecule and side chain epoxidized cardanol glycidyl ether (SCECGE) with approximately 2.45 epoxies (1.0 phenolic+1.45 aliphatic epoxies) per molecule were methacrylated. The methacrylated versions of cardanol based NC514 (NC514VE) and SCECGE (SCECGEVE) epoxy resins were used as cross‐linker units in vinyl ester formulations with methacrylated lauric acid (MFA) and styrene (ST) as bio‐based and synthetic based reactive diluents respectively, at various concentrations (10–40 wt%). The curing reactions of the resins were studied via FTIR and the extent of polymerization was determined for different cross‐linker units in the presence of ST and MFA. Our mechanical and thermomechanical characterizations showed that VER formulations prepared with cardanol based SCECGEVE cross‐linker unit have significantly improved properties than the samples prepared with commercially available counterpart NC514VE using either reactive diluent. These properties of SCECGEVE were also comparable with to that of methacrylated petroleum‐based diglycidyl ether of bisphenol A vinyl ester (DGEBAVE) formulations unlike NC514VE formulations due to more effective side chain functionalization and cross‐linking. [ABSTRACT FROM AUTHOR]

Since wound healing is one of the most important medical challenges and common dressings have not been able to manage this challenge well today, efforts have been increased to achieve an advanced dressing. Mesenchymal stem cells and exosomes derived from them have shown high potential in healing and regenerating wounds due to their immunomodulatory, anti-inflammatory, immunosuppressive, and high regenerative capacities. However, challenges such as the short life of these cells, the low durability of these cells in the wound area, and the low stability of exosomes derived from them have resulted in limitations in their use for wound healing. Nowadays, different scaffolds are considered suitable biomaterials for wound healing. These scaffolds are made of natural or synthetic polymers and have shown promising potential for an ideal dressing that does not have the disadvantages of common dressings. One of the strategies that has attracted much attention today is using these scaffolds for seeding and delivering MSCs and their exosomes. This combined strategy has shown a high potential in enhancing the shelf life of cells and increasing the stability of exosomes. In this review, the combination of different scaffolds with different MSCs or their exosomes for wound healing has been comprehensively discussed. [ABSTRACT FROM AUTHOR]

This study is aimed at the in situ preparation and antibacterial study of silver nanoparticles within the matrix of an eco‐friendly, biocompatible, biodegradable, and bioavailable biopolymer (chitosan) to form Chi–AgNP film via multiple noncovalent interactions between the organic polymer and the nanoparticles. The film is fully characterized by infrared and ultraviolet spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy, and thermogravimetric analysis. The characterization confirms the successful incorporation of silver nanoparticles into the polymeric network. Infrared spectroscopy reveals peaks corresponding to the vibration of functional groups present in chitosan with enhanced intensity and blueshifts caused by the presence of silver nanoparticles. Well‐monodispersed spherical silver nanoparticles with an average size of 10 nm are observed in the Chi–AgNP film. The surface plasmon resonance at 447 nm is consistent with a typical silver plasmon. Furthermore, the antibacterial effects on E. coli and S. aureus were determined and attributed to the release of AgNPs observed by UV absorption. [ABSTRACT FROM AUTHOR]

The objective of this study is to improve the properties of polylactic acid (PLA), a biopolymer produced from renewable resources, without compromising its environmentally friendly "natural composite" properties. The aim was to expand the application range of PLA by making it suitable for the production of high performance composites. With this in mind, it was decided to use inorganic and environmentally friendly materials such as basalt fiber (BF) and boric acid (BA) as reinforcements. Adhesive wear and tensile tests were used to investigate the tribological and mechanical performance of the composites. Differential scanning calorimetry (DSC) and dimensional stability analysis (DSA) methods were used to investigate the thermal properties. Scanning electron microscopy analysis was also used to investigate the morphological properties of the samples. In addition, a matrix modification process using Joncryl®, an epoxy‐based chain extender chemical, was applied to enhance the interfacial interaction between the composite components and improve the composite properties by improving the dispersion of reinforcing materials. As a result of the characterization tests, it was observed that a significant improvement in the properties of the material type containing 10 wt% BF, 0.25 wt% BA and 2 wt% Joncryl® was achieved. A 19% increase in tensile strength of this type of material was observed compared with unreinforced PLA, while the sharp peak increase in the coefficient of friction (COF) curve was shifted from 20 m to 60 m. As a result, it has been presented that environmentally friendly and inorganic materials such as BF and BA can be used to produce composite materials that will serve sectors where the need and use of high performance materials is intense, especially in the automotive, aerospace and aviation sectors. Highlights: The properties of PLA matrix composites were improved by the simultaneous use of BF and BA and the addition of Joncryl®.The structural properties of PLA, an environmentally friendly polymer, have been improved without compromising this characteristic.PLA matrix natural composites with performance that can be used in the automotive, aerospace and aviation sectors have been developed. [ABSTRACT FROM AUTHOR]

Reliable description of stacking interaction of aromatic molecules is important for the understanding structure, stability, and functions of biopolymers. The caffeine molecule is an ideal object for this study as the stacking interactions are the preferential ones for self-associations of this hydrophobic molecule without H-bond donor groups. The analysis of anhydrous caffeine crystal structures revealed five types of caffeine stacking dimers. Geometry optimization of these dimers was performed using two molecular mechanics force fields, ab-initio method Møller Plesset of the second order (MP2), and density functional theory (DFT) with different functionals. The comparison of geometric parameters of the caffeine dimers obtained using different theoretical methods with those in crystals enables us to suggest the methods providing the most reliable stacking characteristics. These methods are: the MP2 with Basis Set Superposition Error correction (MP2/CP), Poltev force field, along with PBE0-DH, SCAN and PBE-D3 functionals of DFT. For the methods, which give the dimer interaction energy close to that obtained by MP2/CP method, the evaluated sublimation enthalpy values are shown to be close to the experimental data. Additionally, MP2/CP, Poltev FF and PBE0-DH functional showed to be the methods that describe well both the energy and geometry of the caffeine stacking dimer. [ABSTRACT FROM AUTHOR]

Stress concentration surrounding wounds drives fibroblasts into a state of high mechanical tension, leading to the delay of wound healing, exacerbating pathological fibrosis, and even causing tissue dysfunction. Here, an innovative skin stress‐shielding hydrogel wound dressing is reported that makes the wound sites shrink as a response to body temperature and then remolds the stress micro‐environment of wound sites to reduce the formation of skin scars. Composed of a modified natural temperature‐sensitive polymer cross‐linked with polyacrylic acid networks, this hydrogel wound dressing has demonstrated a substantial decrease in scar area for full‐thickness wounds in rat models. The physical forces exerted by the wound dressing are instrumental in attenuating the activation and transduction of fibroblasts within the wound sites, thereby mitigating the excessive deposition of the extracellular matrix (ECM). Notably, the wound dressing significantly down‐regulates the expression of transforming growth factor‐β1(TGF‐β1) and collagen I, while concurrently exerting a dramatic inhibitory effect on the integrin‐focal adhesion kinase (FAK)/phosphorylated‐FAK (p‐FAK) signaling pathway. Collectively, the fabrication of functional hydrogels with a stress‐shielding profile is a new route for achieving scar‐less wound healing, thus offering immense potential for improving clinical outcomes and restoring tissue integrity. [ABSTRACT FROM AUTHOR]

Polylactic acid/poly(methyl methacrylate) (PLA/PMMA) composite fibers with high performance were fabricated using melt spinning technique. The crystallization, lamellae orientation and physical properties of composite fibers were investigated systematically. The addition of PMMA (0–20 wt%) has improved the hydrolysis resistance of composite fibers by preventing water molecules from penetrating and diffusing through the fibers, but the strength and heat resistance were reduced at the same time. The stereocomplex crystallites (SC) formed before spinning by introducing poly(D‐lactide) (PDLA) (3 wt%) in poly(L‐lactide) (PLLA) matrix and acted as nucleating agents to enhanced the crystallization and lamellae orientation of PLLA matrix, which improved the physical properties of PLA composite fibers resultful. The tensile strength of PLA fibers with 3 wt% PDLA and 5 wt% PMMA was increased 31% as well as the boiling water shrinkage and the hydrolysis rate were decreased 30% and 33% in relation to PLLA fibers. Finally, the hydrolysis resistance was further enhanced on the basis of realizing high strength and heat resistance, which is of great significance for preparing durable PLA fiber materials and expanding their application. [ABSTRACT FROM AUTHOR]

In this study, the upstream and downstream production processes of curdlan from Priestia megaterium were optimized to enhance its yield. Additionally, a novel extraction method was developed for curdlan recovery. Optimization studies were conducted using Central composite design (CCD). Curdlan yield improved from 0.15 g/L (unoptimized) to 0.46 g/L (3-fold increase) when fermentation was carried out in CCD-optimized media of (w/v) sucrose 20%, urea 0.1%, KH2PO4 0.02%, agitation speed 250 rpm. To further enhance curdlan yield during extraction, ultrasonication was incorporated as a novel step into the conventional method of acid/alkali-assisted curdlan recovery. A two-step optimization was chosen for extraction, namely, one-factor-at-a-time (OFAT) and CCD, wherein the optimized extraction parameters were determined to be 25 s sonication, 1 N NaOH, and 2 h solubilization time. The curdlan yield improved by 1.5-fold (0.70 g/L) post optimization, in comparison with unoptimized conventional extraction step. Finally, the biopolymer was validated through characterization by nuclear magnetic resonance (NMR) which showed characteristic curdlan spectra in the13C and1H NMR studies. To the best of our knowledge, this study represents the first documented report on curdlan extraction using this novel method of ultrasonication. [ABSTRACT FROM AUTHOR]

In recent years, various industrial and agricultural problems have been highlighted, and the pollution of heavy metal ions to water bodies has become a considerable serious phenomenon. Adsorption method is an efficient, low‐cost, and easy to implement method for removing heavy metal ions, which does not produce secondary pollution, and has been widely used in water treatment. Polysaccharides are natural polymers, and their hydroxyl, carboxyl, and amine groups provide feasibility for the synthesis of hydrogels with various structures. The synthesized polysaccharide hydrogel has the characteristics of high adsorption capacity, specific adsorption, nontoxic, and so on. In this review, the kinds of polysaccharide hydrogels and different synthesis methods were discussed first. Then, the adsorption mechanism and different adsorption modes of polysaccharide hydrogels were reviewed. Finally, the effects of different environmental factors on the adsorption capacity of polysaccharide hydrogel were studied. The future research on the adsorption of heavy metal ions by polysaccharide hydrogels was proposed. [ABSTRACT FROM AUTHOR]

Each new class of insecticides that emerged during the development of plant protection gradually found the most suitable group of insect pests for application. At the same time, for each individual insecticide, a balance was sought between its effectiveness, on the one hand, and its safety for non-target organisms and the ecosystem as a whole, on the other hand. Neonicotinoids, diamides and pyrethroids, as effective control agents, dominate the insecticide market, but do not have outstanding performance in selectivity and biodegradation. The biodegradation of insecticides is one of the most important indicators, representing what will be said about the hidden costs for the resulting harvest paid by the environment and human health. Oligonucleotide insecticides (contact unmodified antisense DNA (CUAD) biotechnology, or 'genetic zipper' method) and RNA biocontrols (double-stranded RNA technology) as natural polymers and the next-generation classes of insecticides possess unique characteristics in fast biodegradation and high selectivity in action. While current chemical insecticides require days, months and even years for biodegradation by bacteria and fungi, oligonucleotide insecticides and RNA biocontrols are substantially biodegraded within hours in the presence of nucleases. Nucleic acid-based insecticides have the potential to complement the existing insecticide market and set an eco-precedent for crop protection products where the effectiveness of the insecticide will be determined by its safety for non-target organisms, and other factors being equal, the choice of a particular control agent will be determined by its biodegradability. It should be noted that not a single class of insecticides that once appeared has completely disappeared; rather, it has occupied its niche, gradually declining under the pressure of new classes of insecticides. At the same time, the common trend in plant protection is towards use of insecticides with higher biodegradability, which gives hope for a safer future of the planet. [ABSTRACT FROM AUTHOR]

Approximately one-third of the world's food production, i.e., 1.43 billion tons, is wasted annually, resulting in economic losses of nearly USD 940 billion and undermining food system sustainability. This waste depletes resources, contributes to greenhouse gas emissions, and negatively affects food security and prices. Although traditional packaging preserves food quality, it cannot satisfy the demands of extended shelf life, safety, and sustainability. Consequently, active packaging using biopolymer matrices containing antioxidants and antimicrobials is a promising solution. This review examines the current advancements in the integration of carbon quantum dots (CQDs) into biopolymer-based active packaging, focusing on their antioxidant and antimicrobial properties. CQDs provide unique advantages over traditional nanoparticles and natural compounds, including high biocompatibility, tunable surface functionality, and environmental sustainability. This review explores the mechanisms through which CQDs impart antioxidant and antimicrobial activities, their synthesis methods, and their functionalization to optimize the efficacy of biopolymer matrices. Recent studies have highlighted that CQD-enhanced biopolymers maintain biodegradability with enhanced antioxidant and antimicrobial functions. Additionally, potential challenges, such as toxicity, regulatory considerations, and scalability are discussed, offering insights into future research directions and industrial applications. This review demonstrates the potential of CQD-incorporated biopolymer matrices to transform active packaging, aligning with sustainability goals and advancing food preservation technologies. [ABSTRACT FROM AUTHOR]

Identification of suitable polymeric materials to fabricate microneedles (MNs) for the collection of interstitial fluid (ISF) is a challenge. Here, characterization of different carrageenan‐biopolymer composites for MN patch fabrication intended for ISF collection is reported. Systematic oscillatory rheological studies of composites containing iota‐carrageenan mixed with alginate, gelatin, or pectin are performed to determine the linear viscoelastic region, gel point, tan delta, complex viscosity, and flow transition index. A polynomial equation is derived by relating flow transition index of biopolymer composites and compression strength of fabricated MNs. The biopolymer composite of iota‐carrageenan and gelatin at 2% and 14%, respectively, and CaCl2 crosslinker (80 mm) shows the greatest compression strength sufficient for MNs insertion into the excised porcine skin. MNs swell up on application in an agarose gel model and the ex vivo excised porcine skin model to collect 36 ± 5 and 14 ± 1 µL of fluid within 10 min, respectively. Taken together, it is demonstrated that rheological analysis can be performed to select suitable polymer composites that possess sufficient strength for the skin insertion and swellability for ISF collection. [ABSTRACT FROM AUTHOR]

Biopolymer chitosan sub-micron particles (CSMPs) were prepared by the ionic gelation technique crosslinked with sodium tripolyphosphate co-loaded with trans-cinnamaldehyde (TCIN), and either curcumin (CUR) or paclitaxel (PTX). The size of the spherical CSMPs increased from 118 nm to 136 nm and 170 nm after the loading of TCIN and CUR, whereas the loading of PTX led to a slight decrease (114 nm). Polydispersity indexes of all the samples were smaller than 0.4, indicating monodisperse particles. Zeta potential values higher than +40 mV were determined, which is direct proof of the high stability of these nanoparticles. TCIN and PTX release studies in vitro, at pH 6.5 and 7.4, showed a pH dependence on the release rate with a higher value at pH 6.5. However, CUR was not released from CSMPs probably due to strong interactions with CS biopolymer chains. Cytotoxicity studies showed that the systems loaded with TCIN and PTX were more cytotoxic for HeLa cancer cells than for MDCK cells. Moreover, a synergistic effect against HeLa cells was observed for the TCIN-PTX-loaded CSMP samples. The Sensitivity Index indicated that the CSMPs loaded with TCIN have a prospective attraction to carry and release conventional or new chemotherapeutic drugs. This study demonstrates the in vitro efficiency of the obtained drug delivery system, but in vivo studies are necessary to confirm its potential for clinical applications. [ABSTRACT FROM AUTHOR]

The current strategy for treating osteomyelitis includes surgical procedures for complete debridement of the formed biofilm and necrotic tissues, systemic and oral antibiotic therapy, and the clinical use of cements and three-dimensional scaffolds as bone defect fillers and delivery systems for therapeutic agents. The aim of our research was to formulate a low-cost hybrid nanoparticulate biomaterial using poly(lactic-co-glycolic acid) (PLGA), in which we incorporated the therapeutic agent (ciprofloxacin), and to deposit this material on titanium plates using the matrix-assisted pulsed laser evaporation (MAPLE) technique. The deposited material demonstrated antibacterial properties, with all analyzed samples inhibiting the growth of tested bacterial strains, confirming the release of active substances from the investigated biocomposite. The poly(lactic-co-glycolic acid)-ciprofloxacin (PLGA-CIP) nanoparticle scaffolds displayed a prolonged local sustained release profile over a period of 45 days, which shows great promise in bone infections. Furthermore, the burst release ensures a highly efficient concentration, followed by a constant sustained release which allows the drug to remain in the implant-adjacent area for an extended time period. [ABSTRACT FROM AUTHOR]

Nowadays, plastic contamination worldwide is a concerning reality that can be addressed with appropriate society education as well as looking for innovative polymeric alternatives based on the reuse of waste and recycling with a circular economy point of view, thus taking into consideration that a future world without plastic is quite impossible to conceive. In this regard, in this review, we focus on sustainable polymeric materials, biodegradable and bio-based polymers, additives, and micro/nanoparticles to be used to obtain new environmentally friendly polymeric-based materials. Although biodegradable polymers possess poorer overall properties than traditional ones, they have gained a huge interest in many industrial sectors due to their inherent biodegradability in natural environments. Therefore, several strategies have been proposed to improve their properties and extend their industrial applications. Blending strategies, as well as the development of composites and nanocomposites, have shown promising perspectives for improving their performances, emphasizing biopolymeric blend formulations and bio-based micro and nanoparticles to produce fully sustainable polymeric-based materials. The Review also summarizes recent developments in polymeric blends, composites, and nanocomposite plasticization, with a particular focus on naturally derived plasticizers and their chemical modifications to increase their compatibility with the polymeric matrices. The current state of the art of the most important bio-based and biodegradable polymers is also reviewed, mainly focusing on their synthesis and processing methods scalable to the industrial sector, such as melt and solution blending approaches like melt-extrusion, injection molding, film forming as well as solution electrospinning, among others, without neglecting their degradation processes. [ABSTRACT FROM AUTHOR]

This paper investigates the dissolution of two biopolymers, cellulose and silk fibroin, in a mixture of 1-ethyl-3-methylimidazolium acetate (EmimAc) and dimethyl sulphoxide (DMSO). EmimAc is a promising environmentally friendly solvent currently in wide use but can be limited by its high viscosity, which inhibits the speed of dissolution. To mediate this, DMSO has been used as a cosolvent and has been shown to significantly lower the solution viscosity and aid mass transport. Dissolution experiments are carried out separately for both cellulose and silk fibrion with a range of EmimAc:DMSO ratios from 100 wt% EmimAc to 100 wt% DMSO. Interestingly, the optimal EmimAc:DMSO ratio (in terms of dissolution speed) is found to be very different for the two biopolymers. For cellulose, a mixture of 20 wt% EmimAc with 80 wt% DMSO is found to have the fastest dissolution speed, while for silk fibroin, a ratio of 80 wt% EmimAc with 20 wt% DMSO proves the fastest. These dissolution trials are complemented by rheological and nuclear magnetic resonance experiments to provide further insight into the underlying mechanisms. Finally, we produce hybrid biopolymer films from a solution to show how this work provides a foundation for future effective dissolution and the preparation of hybrid biopolymer films and hybrid biocomposites. [ABSTRACT FROM AUTHOR]

The use of topical antimicrobials in wound healing presents challenges like risk of drug resistance and toxicity to local tissue. Simvastatin (SIM), a lipid-lowering agent which reduces the risk of cardiovascular events, is repurposed for its pleiotropic effect in wound healing. A bioactive bioadhesive polymer-based film forming spray (FFS) formulation of SIM was designed using chitosan, collagen, hyaluronic acid and optimised by employing the DoE approach. Optimised formulation demonstrated moderate viscosity (12.5 ± 0.3 cP), rapid film formation (231 ± 5.6 s), flexibility, tensile strength and sustained drug release (T80 – time for 80% drug release − 9.05 ± 0.7 h). Scanning electron microscopy (SEM) verified uniformly dispersed drug within the composite polymer matrix. SIM FFS demonstrated antimicrobial activity against gram positive and gram negative bacteria. In vivo excision wound model studies in mice affirmed the beneficent role of bioactive polymers and the efficacy of SIM FFS in wound contraction and closure, tissue remodelling and re-epithelization in comparison to standard antimicrobial preparation. Cytokines TNF- alpha, IL-6 were downregulated and IL-10 was upregulated. Biochemical markers; hydroxyproline, hexosamine and histopathology were consistent with wound contraction observed. This is an exploratory effort in repurposing SIM for wound healing in a novel dosage form, underscoring its potential as an alternative to conventional topical antimicrobials. [ABSTRACT FROM AUTHOR]

This study chronicles the seminal contributions of Dr. Raphael M. Ottenbrite, the late Founding Editor of the Journal of Bioactive and Compatible Polymers, to polymer science from the 1970s through 2016. Beginning with an exploration of the biological impacts of anionic polymers, Dr. Ottenbrite's research evolved to include their applications in immunology and cancer therapy. The 1980s marked a pivotal shift toward the synthesis of polymers geared specifically toward biomedical uses. In the 1990s, his work advanced to include sophisticated synthesis methods and surface modification techniques. The 2000s were characterized by a focus on nanotechnology and the innovation of drug delivery systems. His final research phase, from 2011 to 2016, concentrated on the development of biodegradable materials and advanced drug delivery systems. Dr. Ottenbrite's work was a unique blend of polymer chemistry, materials science, and biomedicine, laying a vital groundwork for future interdisciplinary research. [ABSTRACT FROM AUTHOR]

Biopolymers are an attractive green alternative to conventional polymers, owing to their excellent biocompatibility and biodegradability. However, their amorphous and nonconductive nature limits their potential as active biosensor material/substrate. To enhance their bio-analytical performance, biopolymers are combined with conductive materials to improve their physical and chemical characteristics. We review the main advances in the field of electrochemical biosensors, specifically the structure, approach, and application of biopolymers, as well as their conjugation with conductive nanoparticles, polymers and metal oxides in green-based noninvasive analytical biosensors. In addition, we reviewed signal measurement, substrate bio-functionality, biochemical reaction, sensitivity, and limit of detection (LOD) of different biopolymers on various transducers. To date, pectin biopolymer, when conjugated with either gold nanoparticles, polypyrrole, reduced graphene oxide, or multiwall carbon nanotubes forming nanocomposites on glass carbon electrode transducer, tends to give the best LOD, highest sensitivity and can detect multiple analytes/targets. This review will spur new possibilities for the use of biosensors for medical diagnostic tests. [ABSTRACT FROM AUTHOR]

Introduction: Natural biopolymers are used for various purposes in healthcare, such as tissue engineering, drug delivery, and wound healing. Bacterial cellulose and chitosan were preferred in this study due to their non-cytotoxic, biodegradable, biocompatible, and non-inflammatory properties. The study reports the development of a magnetic bacterial cellulose-chitosan (BC-CS-Fe3O4) nanocomposite that can be used as a biocompatible scaffold for tissue engineering. Iron oxide nanoparticles were included in the composite to provide superparamagnetic properties that are useful in a variety of applications, including osteogenic differentiation, magnetic imaging, drug delivery, and thermal induction for cancer treatment. Methods: The magnetic nanocomposite was prepared by immersing Fe3O4 in a mixture of bacterial cellulose-chitosan scaffold and then freeze-drying it. The resulting nanocomposite was characterized using FE-SEM and FTIR techniques. The swelling ratio and mechanical strength of the scaffolds were evaluated experimentally. The biodegradability of the scaffolds was assessed using PBS for 8 weeks at 37°C. The cytotoxicity and osteogenic differentiation of the nanocomposite were studied using human adipose-derived mesenchymal stem cells (ADSCs) and alizarin red staining. One-way ANOVA with Tukey's multiple comparisons test was used for statistical analysis. Results: The FTIR spectra demonstrated the formation of bonds between functional groups of nanoparticles. FE-SEM images showed the integrity of the fibrillar network. The magnetic nanocomposite has the highest swelling ratio (2445% ± 23.34) and tensile strength (5.08 MPa). After 8 weeks, the biodegradation ratios of BC, BC-CS, and BC-CS-Fe3O4 scaffolds were 0.75% ± 0.35, 2.5% ± 0.1, and 9.5% ± 0.7, respectively. Magnetic nanocomposites have low toxicity (P < 0.0001) and higher osteogenic potential compared to other scaffolds. Conclusion: Based on its high tensile strength, low water absorption, suitable degradability, low cytotoxicity, and high ability to induce an increase in calcium deposits by stem cells, the magnetic BC-CS-Fe3O4 nanocomposite scaffold can be a suitable candidate as a biomaterial for osteogenic differentiation. [ABSTRACT FROM AUTHOR]

In this work, chitosan was cross-linked with dialdehyde chitosan to stabilize it and also provide aldehyde segments for the further functionalization with bovine serum albumin. Then, the magnetization procedure was done through the treatment of hybrid polymer with Fe3O4 nanoparticles. BSA was covalently immobilized on the magnetic CS-CSOX biopolymer through condensation of amine groups of amino acid units with the aldehyde functional groups of dialdehyde chitosan. N-terminal peptides, histidine and tryptophan residues of BSA and also the thiol side chain of cysteine and sulfur donor atom of methionine may be as proper binding sites for the copper ions coordination. The catalytic efficiency of Fe3O4@CS-BSA-Cu nanocatalyst was examined in the synthesis of 5-substituted tetrazoles and also 1,4-diaryl-1,2,3-triazoles. The prepared nanocatalyst was separated by an external magnet and reused without significant difference in its activity. [ABSTRACT FROM AUTHOR]

The current study evaluated the potential of crustacean polysaccharide and protein-based biopolymers, namely, chitosan and casein, in ameliorating a low organic soil. The inclusion of these biopolymers will ensure the reusability and recyclability of waste materials derived from the marine industry and dairy industry, respectively. The unconfined compressive strength and consolidated undrained shear parameters were investigated at varying dosages of chitosan and casein (0.5%, 1%, 2%, and 4%) and curing periods (up to 90 days). The compressive strength increased with an increase in the curing period and dosage and led to maximum values of 4.39 and 3.13 MPa for chitosan- and casein-treated soils, respectively, for 4% dosage and 90 days of curing. The effective cohesion (c′) and friction angle (ϕ′) improved after including chitosan and casein. The scanning electron microscopy images revealed that the filler characteristics of chitosan led to strength improvement up to 60 days and developed bond strength via fiber bridging after 60 days of curing at higher dosages. In contrast, the casein–soil mix revealed a higher fibrous structure after a curing period of 28 days, which resulted in strength improvement. This contributed to the highest effective friction angle of 21.57° for the 2% and 60-day-cured casein–soil mix. Casein outperformed chitosan in imparting higher effective shear parameters at 1% and 2% dosages. Fourier transform infrared analysis validated the absence of any new compounds within the soil structure. The research findings on chitosan and casein from the current study recommend the application of these materials for addressing the issues of unstable slopes and pavement subgrade. Practical Applications: The ground improvement industry must shift from environmentally harmful materials to sustainable and nontoxic materials to reduce carbon footprint. Biopolymers are innovative materials derived from various bacteria, plants, and other animals and can impart the required properties for the soils tested (Fatehi et al. 2021). Chitosan and casein are two biopolymers that satisfy the sustainability requirement by being environmentally safe products of waste materials (Chang et al. 2018; Kannan and Sujatha 2023). Applying casein and chitosan has imparted significant improvement in strength to the studied soil. The compressive strength achieved for the fine-grained soils treated with chitosan and casein lies in the range of 0.75–4.39 MPa. Thus, the strength obtained for the treated soils affirms the suitability of these biopolymers in pavement subgrade. The significant improvement in the effective cohesion (c′: 72–179 kPa) and friction angle (ϕ′: 10.57°–21.57°) of amended soils renders the chitosan- and casein-amended samples as excellent shallow foundation materials. Additionally, based on the higher undrained shear strength (125–400 kPa) obtained from consolidated undrained tests, the biopolymers can be recommended for unstable slopes. [ABSTRACT FROM AUTHOR]

The interactions of naturally occurring polymers and medicaments, sodium carboxymethyl cellulose (Na-CMC) and Paracetamol (PCM), have attracted the interest of researchers in a variety of biomedical and pharmaceutical applications areas, such as drug delivery, cosmetics and tissue engineering. In our research described here, the effects of temperature and concentration of Na-CMC/PCM/water (W) mixed solutions were studied at various temperatures ranging from 20 °C to 45 °C. We highlighted that different regions can be distinguished in the aqueous Na-CMC/PCM/W complexes, depending on the composition and electrostatic interactions of the solutions, which are associated with significantly different phase behaviors. [ABSTRACT FROM AUTHOR]

Antibacterial products have gained considerable attention from both the academic and industrial communities due to the transmission of several infectious diseases which has raised public awareness of the disinfection pathways of such highly infectious bacteria. Among the materials that have raised public awareness are rubber composite materials as they are present in many different applications, such as medical apparatus, health care products, food packaging, and house furnishings Therefore, the development of rubber‐composite‐based materials with antibacterial activity is crucial to avoid the propagation of pathogens. In this regard, researchers have directed their focus toward the development of innovative additives with antibacterial properties to enhance the antibacterial activities of rubber composites. Several promising additives have emerged, most notably metal and metal oxide nanoparticles, biopolymers, plant‐derived materials, and synthetic organic compounds. The studies have shown that the incorporation of these additives endows the rubber composites with antibacterial properties, making them applicable in a range of biomedical uses. In light of these findings, the present review aims to cover recent works to improve the antibacterial properties of rubber composites using different additives. Highlights: Rubber composite materials, found in various applications like medical apparatus and food packaging, have raised public awareness of infection prevention.Development of rubber‐composite‐based materials with antibacterial activity is crucial for preventing pathogen propagation.Researchers focus on innovative additives, including metal nanoparticles, biopolymers, plant‐derived materials, and synthetic organic compounds, to enhance antibacterial properties.Incorporating these additives into rubber composites endows them with antibacterial properties, suitable for biomedical applications. [ABSTRACT FROM AUTHOR]

Advancements in polymers have made significant contribution in diverse application‐oriented fields. The multidisciplinary application of polymers generates a range of strategies, which is applicable in a wide range of biomedicines. Polymeric compounds such as hydrogels have been explored globally as a potent biomaterial that can furnish essential attributes due to their three‐dimensional (3D) soft and highly hydrophilic polymeric network. These hydrogels have been used extensively in various applications due to their biocompatible, biodegradable, and biosorption nature. However, they have some limitations, owing to their soft nature, low mechanical properties, and unsatisfactory degradation profile. Therefore, there is a need to develop novel, stronger, and more durable hybrid hydrogels with enhanced biocompatible and multifunctional properties. The current review gives a broad spectrum of hybrid hydrogels with its importance and significance. Further, the review highlights the strategies of generation of hybrid hydrogels reinforced with nanomaterials, biomaterials, and nanobiocomposites along with their advantages and disadvantages. The review also features various applications of these hybrid hydrogels in the field of biomedicines, photocatalysis, agriculture, and food industry over the last 5 years. This review will give a comprehensive overview to researchers working in the field of hybrid hydrogels development. [ABSTRACT FROM AUTHOR]

For almost a decade, various studies have been carried out to prove the suitability of nano additives in enhancing the geotechnical properties of soil. Yet, this line of research is still in its elementary stage, restricting itself to laboratory tests to determine soil's index and engineering properties blended with varying dosages of nano additives. In other words, research on practical applications of nano additives for soil stabilization is scarce. The present work attempts to investigate the suitability of three different nanomaterials as a load-bearing stratum for shallow foundations. The nano additives were chosen in such a way that each of them is from a different origin. One of them is nano calcium carbonate (inorganic) whereas the other two are nano-sized varieties of natural biopolymers, namely nano chitosan (crustacean-based) and nano carboxymethyl cellulose (plant-based). A series of laboratory tests were initially conducted to determine the strength of all three nano-additive-treated soils at different dosages, which were investigated for 180 days to ensure their long-term performance. This was followed by a foundation model study on untreated soil and on soil treated with optimal dosages of nano additives. The results were validated using finite element software followed by a parametric study to optimize the depth of soil stabilization. It was observed that all three nano additives exhibited a better performance when the top layer had the optimal dosage and the subsequent layers had a relatively lesser dosage. [ABSTRACT FROM AUTHOR]

Inefficiently treated wastewater, which contains a high concentration of pollutants, is hazardous when it is mixed with the clean water of rivers and lakes. Nitrate in particular is a major global problem that leads to eutrophication and poses a threat to both aquatic ecosystems and human health. To address this issue, this work assessed the efficiency of polymeric cryogel (PC) and biopolymer (EPS)-blended composites (EPS@PC) in removing nitrates. Tests were also conducted to quantify the decrease in phosphate, chloride ions, and chemical oxygen demand (COD) in real water samples taken from the Ankara stream, which receives effluents from both urban (UWTP) and industrial (IWTP) wastewater treatment plants. Five different columns with varying adsorptive properties were prepared, some of which were combined with iron. The EPS-@PC-C5 column demonstrated the highest adsorption ratio for nitrate removal compared to the other tested columns. The EPS@PC-C5 achieved a high removal efficiency of 126.38 mg nitrate/g and showed COD reduction ranging from 60.2 to 94.1%. The removal ratio of chloride concentration varied between 56.0 and 75.7%, while the removal of phosphates ranged from 87 to 99%. Columns composed of EPS (EPS@PC) with both negatively and positively charged ligands are dependable and suitable options for water remediation. [ABSTRACT FROM AUTHOR]

Developing biodegradable material alternatives is crucial to address the fossil-based plastic pollution in marine ecosystems. Natural biodegradable polymers like cellulose exhibit potential plastic alternatives. However, their susceptibility to water and moisture poses challenges when blending with hydrophobic polymers. Thus, chemical modification is often required to enhance cellulose dispersion in hydrophobic polymer matrices, which may hinder its inherent biodegradability. In this study, the aquatic biodegradation and degradation mechanisms of lignocellulose-polyester composite films under aerobic conditions were for the first time explored in simulated freshwater and real seawater environments. The composite films were produced by blending cellulose nanofibrils (CNFs) with polycaprolactone (PCL), a hydrophobic polyester, using lignin nanoparticles (LNPs) as an interfacial compatibilizer. The structural and morphological changes of the composite films were studied using Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), and scanning electron microscopy (SEM). Despite the use of LNPs (poorly degradable in aquatic conditions) and the composite films' hydrophobicity, the presence of up to 25 wt% PCL and 5wt% LNPs did not prevent the composites from achieving > 85% biodegradation within 42 days, in both fresh water and seawater conditions. The incorporation of CNFs increased the water uptake capability of PCL which helped to increase the films' porosity, in turn enhancing the film degradation process. This study confirmed that hydrophobizing nanocellulose with biodegradable polyesters and LNPs can preserve the nanocellulose's inherent coveted biodegradability. Hence, this sustainable approach to developing bio-based composites supports responsible material development, disposal, and end-of-life management. [ABSTRACT FROM AUTHOR]

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

In this research, the synergistic corrosion inhibition effect of hybrid organic/mineral inhibitors in a 3.5 wt.% NaCl solution was investigated. For this purpose, a polydopamine/molybdate hybrid was used for the first time. The reason for choosing polydopamine was the existence of unique functional groups in its structure and the ability of high adhesion to surfaces. At the same time, the rapid inhibitory behavior and the possibility of complex formation with organic substances and iron cations were essential factors in choosing molybdate as an inorganic inhibitor. Through open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), and polarization analyses, the combined inhibitors' electrochemical behavior was explored. From the EIS analysis results, the maximum inhibition efficiency of 86% and synergism index of 1.33 were obtained for the sample dipped in the solution containing 250:750 ppm PDA and MoO42− compounds after 24-h immersion at room temperature. The polarization test revealed that the notable decrease of i corr (corrosion current density) compared with the uninhibited sample 12.5 to 1.3 μ A / cm 2 and the maximum inhibition efficiency of 90% were related to the 250:750 ppm PDA:MoO42− mixture among different inhibited samples. Fourier transform infrared spectroscopy (FT-IR) and Raman analyses were utilized to investigate the complex formation between PDA, MoO42−, and Fe cations. Furthermore, the morphology, elemental composition, and hydrophilicity/hydrophobicity of the submerged samples' surfaces were studied through field emission scanning electron microscope/energy-dispersive X-ray spectroscopy (FE-SEM/EDS) and water contact angle analyses. [ABSTRACT FROM AUTHOR]

The excess phosphate in water leads to eutrophication. To reduce eutrophication, alginate-pectin supported bentonite-hydrotalcite cross-linked with zirconium-cerium bimetal ions based biopolymeric composite namely APBHZC bimetallic composite was synthesized for phosphate removal from water. SEM, EDAX and FTIR techniques were used to classify the physico-chemical properties of APBHZC bimetallic composite. Adsorption studies like pH, co-ions, temperature and contact time were carried out under batch method. The developed APBHZC bimetallic composite achieved a maximum phosphate adsorption capacity of 42.50 mg/g within 40 min. The pH of the solution interferes with phosphate adsorption using APBHZC bimetallic composite. Among the co-ions, sulphate ions affected the phosphate adsorption onto APBHZC bimetallic composite. Isotherm studies were described that the phosphate adsorption onto APBHZC bimetallic composite was multilayer adsorption process and it was followed by Freundlich isotherm model. Kinetic studies illustrated that the intraparticle diffusion and pseudo-second-order were more suitable models for phosphate adsorption onto APBHZC bimetallic composite. Thermodynamics studies revealed that the phosphate adsorption on bimetallic composite was spontaneous and endothermic in nature. The developed APBHZC bimetallic composite can be reused upto 4 cycles. In addition, the appropriateness of APBHZC bimetallic composite at field conditions was also checked. [ABSTRACT FROM AUTHOR]

Inhibitory properties of an eco‐friendly composition based on gum arabic polysaccharide and citric acid salt–sodium citrate for corrosion prevention of low‐carbon steel in neutral environment was investigated. Corrosion resistance of low‐carbon steel in a 0.1% NaCl solution with and without composition after 3 and 24 h immersion was investigated by electrochemical and weight loss methods. The inhibitory composition with 0.5 g/L concentration was obtained by adding 0.25 g/L of gum arabic and 0.25 g/L of sodium citrate in 1L 0.1% NaCl solution. It was established that the inhibitory efficiency of the composition is enhanced with increasing concentration (0; 0.25; 0.50; 0.75; 1; 1.50; 2.0 g/L) and reaches a maximum at 2.0 g/L of each component. The protective effect of the composition is determined by the combination of two compounds of different natures, which have hydroxyl and carboxyl functional groups. The inhibitory ability of the composition is due to the dominant competitive adsorption between citrate anions with gum arabic and chloride ions on the steel surface. Adsorption of citrate and gum arabic on the steel surface corresponds to the Frumkin isotherm, and the Gibbs energy value was −12.25 kJ/mol, which indicates physical adsorption. The morphology and chemical content of the steel surface after immersion in a solution with an inhibitory composition were investigated by the scanning electron microscopy (SEM) and EDX analysis. The formation of a protective film based on gum arabic and citrate probably occurs by chelation, which effectively blocks the access of corrosively active Cl− ions. It was shown that the corrosion rate Km was 0.42·10−5 g/cm2·h and the inhibitory efficiency for protection of the steel was 80.4% after 24 h immersion in a 0.1% NaCl solution with composition. [ABSTRACT FROM AUTHOR]

Lignins, abundant aromatic biopolymers and one of the major components of lignocellulosic biomass, remain the most underutilized renewable bioresources of aromatics and hydrocarbons on the Earth. Numerous physical and chemical processes have been developed for lignin valorization; however, they generally suffer from environmentally unfriendly, harsh conditions and lack reaction specificity. On the other hand, milder methods involving biocatalysts exist but are impeded by many limitations, such as cofactor regeneration, deleterious enzyme–lignin interactions, and low stability. In this work, we attempt to eliminate the constrains encountered in enzyme‐based lignin valorization processes through the development of a novel electrochemically assisted bioprocess. This “all‐in‐one” biocathode incorporates a hybrid electrocatalytic interface combining a hydrogen peroxide‐generating passive air‐breathing gas diffusion electrode with an immobilized hydrogen peroxide‐consuming lignin peroxidase on a single surface and catalyzing the depolymerization of lignins. The ligninolytic potential of this bioelectrochemical device is demonstrated using both lignin models (veratryl alcohol and veratrylglycerol β‐guaiacyl ether) and a technical lignin at room temperature in aqueous media with the reaction efficiency of 14.9% per hour. [ABSTRACT FROM AUTHOR]

Multicellular organisms generate complex morphologies required for their function. Organisms control these morphologies by tuning active forces and by altering the emergent 'material properties' of a tissue, i.e. the rheology of the tissue. In many cases, organisms take advantage of dramatic changes in the rheology that occur when the material undergoes a rigidity transition from a fluid-like or floppy state to a solid-like or rigid state. This transition in turn depends on internal parameters at the scale of cells and molecules. This review highlights recent theoretical work identifying the mechanisms that drive such transitions, so that biologists can look for these mechanisms in in vivo or in vitro systems. We discuss two main types of transition: a first-order rigidity transition that depends on the connectivity of small-scale structures, such as the number of contacts between cells or the number of branch points in a biopolymer network; and a second-order rigidity transition that depends on the geometry of small-scale structures, such as the shape of cells or the distance between crosslinks in a polymer network. We provide examples of each type of transition in model organisms and discuss methods for distinguishing between the mechanisms in future experiments. In this review, Lisa Manning distills recent theoretical work identifying the mechanisms that drive rigidity transitions in mechanical networks, so that biologists can look for these mechanisms in specific in vivo or in vitro systems. [ABSTRACT FROM AUTHOR]

Bio‐based flexible dielectric substrates have gained tremendous attention for their potential to reduce environmental risks from nonbiodegradable electronic waste. The present study demonstrates the fabrication of facile, nontoxic, and biodegradable chitosan‐based flexible dielectric substrate using graphene nanoplatelet (GNP) as a nanofiller. The detailed impact of different concentrations of GNP (1, 2, and 3 wt%) into the chitosan (CS) matrix was studied on physicochemical, morphological, mechanical, electrical, and thermal properties. The fabricated CS/GNP composites showed improved mechanical strength, thermal stability, and electrical properties compared with unmodified CS film. The composites exhibited excellent thermal stability (200°C) with a promising biodegradation rate (within 6 days). The mechanical strength of the unmodified CS film was increased unequivocally with 2 wt% GNP loading with tensile strength of 23.56 Mpa. Furthermore, the current–voltage (I–V) characteristic curves for CS/GNP (2%) and CS/GNP (3%) showed similar current conduction and ohmic behavior in flat, bending, and flat‐after‐bending modes. The dielectric measurements revealed that the CS/GNP composite with 2 wt% filler exhibited optimal performance having permittivity (έ) of 32.71 (at 102 Hz) with low dielectric loss of 0.04 (at 106 Hz). These results suggest that the dielectric films offer strong prospects as an eco‐friendly alternative for various applications. Highlights: Biodegradable chitosan‐based flexible dielectric films were prepared.Films were made using a simple solvent casting method with 1–3 wt% GNP filler.Optimum physicochemical and electrical properties were seen at 2 wt% GNP.CS/GNP (2%) film exhibited ohmic behavior in both flat and bending modes.Excellent dielectric properties were achieved at 2 wt% GNP filler. [ABSTRACT FROM AUTHOR]