Search Results (1,131)

Diabetic foot ulcers (DFUs) are among the most severe complications affecting diabetic patients, and dressing therapy is one of the standard treatments for DFUs. However, traditional dressings are inadequate for addressing the complex microenvironment of DFUs. Consequently, advanced natural polymer-based dressings have attracted extensive research attention in diabetic foot care due to their biocompatibility, low immunogenicity, and biodegradability. These natural polymer materials include collagen, gelatin, chitosan (CS), hyaluronic acid (HA), alginate, and cellulose. This review systematically analyzes the pathophysiological mechanisms underlying the difficult healing of DFUs and the advantages of natural polymer-based dressings in diabetic wound healing, highlights preclinical studies, and synthesizes evidence from clinical research. Moreover, we pinpoint the challenges associated with these dressings and propose future directions for the improvement of diabetic wound care. Full article

Chitosan, produced through deacetylation of chitin from crustacean byproducts and, increasingly, fungal biomass and insects, is attracting food-sector interest because it combines antimicrobial activity, antioxidant capacity, biodegradability, and film-forming behavior in a single polymer. This review discusses how source, molecular weight (MW), degree of deacetylation, solubility, and charge density shape its performance in food systems. The paper then follows the main technological routes now tested or used: edible films and coatings, hydrogels, cryogels, nanoparticles, microcapsules, and hybrid matrices. These formats can protect fresh produce, meat, poultry, fish, seafood, and dairy foods, while also supporting beverage clarification, emulsion control, release of natural antimicrobials or antioxidants, and freshness monitoring in active or intelligent packaging. The evidence indicates strong promise, especially where microbial growth, lipid oxidation, moisture transfer, and short shelf life remain limiting factors. Yet, wider industrial use is still slowed by water sensitivity, sensory effects, raw-material variation, cost, process scale-up, and regulatory alignment. Future work should move beyond laboratory efficacy and address reproducible production, food-specific validation, and consumer acceptance. Full article

Polymer-based active packaging systems incorporating natural bioactive agents have attracted growing interest as eco-friendly alternatives to traditional food packaging materials. In this study, Pistacia lentiscus essential oil (PLEO) was incorporated into PCL/gelatin nanofibrous mats fabricated via solution blow spinning (SBS) to develop multifunctional and biodegradable active packaging materials. Neat PCL, gelatin-blended PCL (PCL–G) and PCL–G mats containing 5, 10 and 20 wt.% PLEO were produced and thoroughly analyzed for their morphological, chemical and functional characteristics. Morphological investigation revealed a smooth, bead-free fibrous structure in all samples. The average fiber diameter (AFD) increased from 239 nm to 320 nm with the addition of gelatin to the PCL matrix, while the incorporation of different concentrations of PLEO caused only minor changes. The results showed that as the concentration of PLEO increased, the antioxidant activity of the nanofibrous mats also increased. This enhancement is potentially linked to the rich content of bioactive molecules such as β-pinene, terpineol and verbenol. The 2,2-diphenyl-1-picrylhydrazyl scavenging activity improved from 6.4% (PCL) to 60% (PCL–G–20PLEO), and ABTS activity rose from 8.7% to 72%. In addition, antimicrobial evaluation showed inhibition zones of 12.5 mm against Escherichia coli and 14.2 mm against Staphylococcus aureus for the PCL–G–20PLEO nanofibrous mats. In 14-day storage tests on Kashar cheese, PCL–G–10PLEO and PCL–G–20PLEO mats reduced microbial counts by more than 2 log units compared with the control and effectively slowed yeast and mold growth. These findings confirm the potential of the PCL–G–PLEO nanofibrous mat as novel active packaging materials for preserving dairy products such as Kashar cheese. Full article

Ring-opening polymerization (ROP) of β-lactones yields biodegradable and bioresorbable polyesters exhibiting potential utility in medicine and environmental protection. β-butyrolactone (BL) is especially interesting, as it yields polymers analogous to natural poly(3-hydroxybutyrates) produced by bacteria, fungi, and enzymes in nature. The biopolymer produced by these microorganisms is isotactic. While it can be synthesized biotechnologically through the bacterial fermentation of substrates, such as sucrose, corn, and sugar, laboratory production typically involves the ring-opening polymerization of BL. However, the latter process is mainly atactic, syndiotactic, or partly isotactic, and other β-substituted β-lactones are less well-known. Ring-opening polymerization is an excellent pathway for the production of poly(β-lactones). This critical review presents the different conditions required to synthesize poly(β-lactones) and a broad overview of the different kinds of ROPs, i.e., anionic, cationic, coordinative, supramolecular-based, and enzymatic processes. A great variety of initiators/catalysts have been studied, covering both metal-based and metal-free systems (organo- and biocatalysts). In this review, several mechanisms of β-lactone polymerization are presented and discussed, especially with regard to the processes’ initiation steps. Full article

Mucoadhesive drug delivery systems have emerged as a promising strategy to enhance the therapeutic efficacy of pharmaceuticals by improving drug residence time, bioavailability, and site-specific targeting. Among various materials investigated, biopolysaccharides have gained significant attention due to their biocompatibility, biodegradability, non-toxicity, and inherent mucoadhesive properties. Natural polymers such as chitosan, alginate, pectin, hyaluronic acid, and cellulose derivatives exhibit strong interactions with mucosal surfaces through hydrogen bonding, electrostatic interactions, and polymer chain entanglement. These properties enable prolonged drug retention at mucosal sites, controlled drug release, and enhanced permeation across biological barriers. Mucoadhesive biopolysaccharides have been explored for diverse routes of administration, including oral, buccal, nasal, ocular, vaginal, and pulmonary delivery. Furthermore, chemical modification and nanostructuring of these polymers have expanded their functionality, enabling targeted delivery of small molecules, proteins, peptides, and nucleic acids. This review highlights the mechanisms of mucoadhesion, key biopolysaccharides used in drug delivery, formulation approaches, and recent advances in their application as versatile platforms for novel therapeutic delivery systems. The continued development of mucoadhesive biopolysaccharide-based carriers holds substantial potential for improving treatment outcomes and patient compliance. Full article

Phase-inversion in situ implants (PIISIs) represent a versatile polymer platform in which the rational choice of matrix former and solvent system directly governs the macroscopic properties of the resulting depot. This study applied a Quality by Design (QbD) approach to rationalize a bleached shellac–based PIISI, with particular focus on the physicochemical interactions between the polymer and the injection vehicle. Bleached shellac—a natural, low-cost, biodegradable oligomeric resin bearing –COOH, –OH, and ester functional groups—was selected as the matrix former and screened in seven neat solvents and five 1:1 binary combinations at 25% (m/m). Twelve formulations were evaluated against a predefined set of critical quality attributes, including injectability, phase-inversion kinetics, solvent diffusion volume, and implant structure (n = 5 per formulation; mean ± standard deviation (SD); one-way analysis of variance (ANOVA) with Tukey’s post hoc test, p < 0.05). Three lead solvent systems—propylene glycol/N-methylpyrrolidone (PG+NMP), PG/dimethyl sulfoxide (PG+DMSO), and DMSO/benzyl alcohol (DMSO+BA)—were identified as those providing an optimal balance between hydrogen-bond donor/acceptor solvation and controlled solvent extraction. In the second stage, shellac concentration (20–35%) was optimized, with 30% shellac in PG+NMP yielding the fastest phase inversion (~50 s), a structurally uniform matrix, and the lowest swelling (22%). A working mechanistic framework consistent with all observed critical quality attribute (CQA) trends in which solvent hydrogen-bond donor/acceptor balance and water miscibility govern implant architecture is proposed, and it is intended as a hypothesis-generating basis for the rational design of PIISI formulations; direct validation by spectroscopic, thermal-analytical, and biological methods is identified as the next step. The developed formulations are presented as a preliminary physicochemical platform; biological validation (in vitro cytocompatibility and inflammatory response assessment) is required before the system can be considered a validated formulation for dental drug delivery. Full article

Microplastic pollution has become a significant environmental concern due to its persistence and widespread impact across ecosystems. These plastic particles (1 μm to 5 mm), originating from larger plastic debris or industrial sources, accumulate in diverse habitats, affecting biodiversity and human health. Microplastics resist natural degradation, posing challenges to both ecological sustainability and waste management strategies. Although numerous studies have explored microbial degradation, most existing research focuses primarily on bacteria, leaving the role of filamentous fungi comparatively underexplored. This represents a significant research gap, because fungi secrete a variety of extracellular enzymes, including laccases, peroxidases, and esterases, which play crucial roles in the breakdown of synthetic polymers. These enzymes facilitate the depolymerization of microplastics by targeting polymer chains and increasing their susceptibility to further microbial degradation. However, the underlying enzymatic mechanisms and their effectiveness in microplastic remediation remain insufficiently characterized. Here, we critically review the potential of filamentous fungi for microplastic biodegradation, emphasizing their oxidative and hydrolytic enzyme systems, biosurfactant production, and mechanisms of adsorption and mineralization. The novelty of this review lies in consolidating the most recent mechanistic insights into fungal-driven depolymerization pathways, integrating them with advances in genetic engineering, bioprocess scale-up, and regulatory perspectives, areas rarely combined in previous reviews. We identify current limitations related to environmental applicability, enzyme accessibility, and the lack of standardized protocols, and propose strategies to overcome these challenges through enzyme immobilization, microbial consortia design, and synthetic biology approaches. By addressing these gaps, filamentous fungi may contribute to the development of sustainable strategies for plastic pollution mitigation and support circular economy approaches toward polymer biodegradation. Full article

The food-packaging sector is undergoing a major transition driven by the environmental burden associated with petroleum-based plastics and the increasing demand for sustainable alternatives. In this context, biodegradable packaging materials capable of extending food shelf life through active preservation functions have attracted considerable interest. Cellulose is the most abundant natural polymer and an attractive candidate for sustainable packaging; however, it lacks intrinsic antimicrobial activity. In the present study, innovative carboxymethyl cellulose (CMC)-based composite films were developed by incorporating zinc oxide (ZnO) nanoparticles (NPs) and thyme essential oil (TEO) as antibacterial active agents. The obtained films exhibited strong antibacterial activity against both Escherichia coli and Staphylococcus aureus, completely eliminating planktonic cell viability after 3 h of contact and producing inhibition zones of up to 30 mm. In addition to their biological performance, the composite films showed improved mechanical and functional properties. ZnO NPs appear to act as multifunctional junctions within the CMC matrix, while the dispersed TEO droplets contribute, together with the inorganic phase, to reduced water-vapor transfer. The films retained good transparency in the visible range while exhibiting UV-A transmittance below 7%, indicating enhanced light-barrier performance. Preliminary tests on soft cheese indicated shelf-life extension up to 14 days at 4 °C, while in inoculated cheese slices packed in the composite films, S. aureus was not detected from the 3rd day. Overall, these results demonstrate the potential of CMC/ZnO/TEO composite films as biodegradable active packaging materials for perishable food products. Full article

Hydrogel scaffolds have emerged as a central platform in tissue engineering due to their ability to mimic the extracellular matrix and support cellular functions. Among natural polymers, chitin and its derivative chitosan have emerged as valuable candidates for hydrogel scaffold development because of their biodegradability, compatibility with living tissues, and inherent biological functionality; however, their distinct and complementary roles in hydrogel scaffold design are often insufficiently differentiated in the literature. This review provides a comprehensive and mechanism-driven analysis of chitin- and chitosan-based hydrogel scaffolds, emphasising how their molecular structure governs network formation, mechanical performance, and biological functionality. Chitin is highlighted primarily as a structurally robust and crystalline component suitable for reinforcement. In contrast, chitosan serves as a versatile, soluble, and chemically reactive matrix enabling various crosslinking and functionalization strategies. Recent advances in physical, ionic, and covalent crosslinking as well as composite scaffold engineering, biofunctionalization, and emerging fabrication approaches such as injectable systems and three-dimensional bioprinting are systematically examined. The relationships between scaffold architecture, degradation behaviour, and cellular responses are discussed in key tissue engineering applications, including bone, cartilage, skin, and nerve regeneration. Importantly, this review introduces a unified structure–property–function framework that distinguishes the roles of chitin and chitosan within hydrogel systems and links crosslinking mechanisms to application-specific performance requirements, an aspect not comprehensively addressed in previous studies. Current challenges related to mechanical limitations, material variability, and clinical translation are critically evaluated, and future perspectives for the rational design of next-generation biomimetic hydrogel scaffolds are proposed. Full article

Polylactic acid (PLA), a biodegradable polymer derived from renewable resources, represents a promising candidate for sustainable textiles. Nevertheless, its practical application remains limited by the requirement for high-temperature dyeing, which can induce polymer hydrolysis and lead to the loss of fiber strength. To address this limitation, PLA fabric was treated with an eco-friendly natural deep eutectic solvent (NaDES) composed of glycerol and citric acid. The treatment was found to enhance fiber surface roughness and internal looseness, which facilitated dye diffusion and allowed for a significant reduction in dyeing temperature. When dyed with microbial prodigiosin, the treated PLA fabric achieved a color depth at 70 °C that was equivalent to untreated fabric at 90 °C, while also exhibiting a 93.56% bacteriostatic rate against Staphylococcus aureus due to the inherent antibacterial property of microbial prodigiosin. This work provides a novel and sustainable strategy for the eco-friendly dyeing of PLA textiles. Full article

This review analyzes the advances over a five-year period in the development of polymeric sorbents for the purification of aqueous media from key classes of pollutants: hydrocarbons (crude oil, diesel fuel), organic dyes, pharmaceuticals (antibiotics), pesticides, herbicides, volatile organic compounds, and polycyclic aromatic hydrocarbons. Attention is paid to the analysis of structure-property-performance relationships, with an emphasis on comparing materials derived from renewable natural feedstocks (such as cellulose, chitosan, terpenes, vegetable oils, and aloe vera) with synthetic polymers. The analysis reveals that biopolymer-based sorbents exhibit comparable or superior sorption capacities combined with environmental safety, biodegradability, and low cost. The key sorption mechanisms include physical adsorption, hydrophobic interactions, and electrostatic interactions. Despite persisting challenges related to scalability, stability in real-world environments, and the need for efficient regeneration protocols, a convergent approach that combines the advantages of modified natural polymers and functional synthetic components appears to be the most promising strategy for developing cost-effective and sustainable technologies for the restoration of water quality. Full article

The transition toward sustainable food packaging requires the integration of biodegradable materials with functional bioactivity. Chlorogenic acid (CGA), a naturally abundant polyphenol, has emerged as a multifunctional compound with the capacity to simultaneously modulate polymer structure and impart active and intelligent functionalities. This review critically examines recent advances in CGA-containing packaging systems, covering fabrication strategies from physical incorporation and chemical grafting to nanostructured and stimuli-responsive architectures. The analysis reveals that CGA plays a dual role. At the molecular level, it regulates the polymer network structure through hydrogen bonding, covalent interactions, and conformational rearrangement. This, in turn, influences mechanical strength, barrier performance, and optical properties. Functionally, CGA provides antioxidant and antimicrobial activity, although its effectiveness depends strongly on the incorporation strategy and concentration. Notably, nanostructured systems and conjugation approaches enable controlled release and enhanced stability. These methods overcome limitations associated with rapid diffusion and environmental degradation, including oxidation, UV exposure, and pH-related instability. Despite these advances, key challenges remain, including CGA instability, uncontrolled release behavior, and limited regulatory and scalability data. Furthermore, while CGA is well established in active packaging, its application in intelligent systems remains limited in the literature, with only a few studies reported on its intelligent applications. Overall, this review highlights the structure–function relationships governing CGA-containing packaging systems and outlines future directions for the rational design of cost-effective, scalable, and multifunctional packaging systems, positioning CGA as a promising component in sustainable strategies for food preservation and waste reduction. Full article

Polysaccharides are structurally diverse biopolymers composed of multiple monosaccharide units linked through glycosidic bonds. Their complexity, biodegradability, and functional versatility make them integral to biological systems as well as modern industrial application. Sourced from plants, fungi, marine organisms, animals, and microbes, these natural polymers exhibit a broad spectrum of bioactivities, including antioxidant, antimicrobial, immunomodulatory, and physicochemical protective functions. In the context of food preservation, polysaccharides have gained significant attention as sustainable alternatives to synthetic preservatives and conventional packaging materials. This review summarizes the classification and structural attributes of polysaccharides that influence their functional performance, particularly their ability to scavenge free radicals, inhibit foodborne pathogens, and form protective barrier systems. Special emphasis is placed on their use in edible films, coatings, and encapsulation systems that enhance the shelf life of fruits, vegetables, meats, dairy, beverages, and bakery products. Challenges related to stability, sensory impact, and regulatory compliance are also discussed. Overall, polysaccharides demonstrate substantial potential as eco-friendly, bioactive packaging agents and controlled-release carriers, contributing to safer, greener, and more sustainable food preservation technologies. Full article

Soil degradation in both agricultural and urban environments is accelerating due to intensive land use, plastic pollution, construction practices, and climate change, threatening ecosystem stability, food security, and carbon storage capacity. This review synthesizes current advances in biopolymeric materials as regenerative alternatives to conventional soil management approaches. Biopolymers derived from natural sources—including polysaccharides, proteins, and lignin-based compounds—are examined for their multifunctional roles in improving soil structure, enhancing water retention, optimizing nutrient delivery, stabilizing slopes, and supporting pollutant immobilization. Recent developments highlight the emergence of stimuli-responsive hydrogels, controlled-release fertilizer matrices, and composite soil conditioners capable of simultaneously addressing water stress, salinity, erosion, and contamination. In parallel, biodegradable agricultural films and in-soil degradable materials offer pathways to reduce microplastic accumulation while maintaining agronomic performance. Beyond agriculture, bio-based construction materials and bio-receptive design strategies extend biopolymeric interventions into the built environment, promoting soil permeability, microbial diversity, and circular material flows. The review emphasizes the need for context-specific formulation, long-term field validation, and life-cycle assessment to ensure environmental safety and scalability. By integrating soil science, polymer chemistry, and regenerative design, biopolymeric systems are described here as tools for restoring soil health and fostering resilient urban–rural ecosystems under conditions of environmental change. Full article

Poly(lactic-co-glycolic acid) (PLGA) is a biodegradable biopolymer widely used in advanced drug delivery systems (DDSs) due to its biocompatibility, controllable degradation behavior, and tunable physicochemical properties. Its degradation into naturally metabolized lactic and glycolic acids makes PLGA particularly attractive for biomedical applications, positioning PLGA nanoparticles as versatile carriers that bridge material design and therapeutic delivery. In this context, electrospray (electrohydrodynamic atomization) has emerged as an innovative and scalable processing technique that enables precise control over nanoparticle size, morphology, and internal structure under mild conditions, which is particularly suitable for engineering biopolymer-based DDSs. This review provides a comprehensive overview of electrospray-fabricated PLGA nanoparticles, with emphasis on the relationship between processing conditions, polymer structure, and functional performance. The fundamental mechanisms governing drug release, including diffusion, polymer degradation, and their combined effects, are discussed in relation to PLGA properties. The influence of electrospray parameters on nanoparticle formation, morphology, and internal architecture is analyzed, highlighting how process–structure–property relationships can be tailored to achieve specific release profiles. Structural design strategies, including single-matrix, core–shell, and surface-functionalized nanoparticles, are further examined as approaches to enable controlled and sequential dual-DDSs. In addition, emerging modeling and computational approaches are briefly discussed as complementary tools for understanding and optimizing nanoparticle behavior. Challenges and technical problems, such as substrates for nanoparticle detachment, are discussed. Full article