Search Results (180)

Gellan gum (Gellan), a versatile polysaccharide applied in gel formation and prebiotic formulations, is often processed to tailor its molecular properties. Previous studies employed gamma irradiation and chemical hydrolysis, though without addressing systematic scaling behavior. This study investigates the structural and conformational modifications of Gellan in dilute aqueous salt solutions using a safer and eco-friendly approach: atmospheric low-dose electron beam (e-beam) degradation coupled with viscosity analysis. Native and E-beam-treated Gellan samples (0.05 g/cm³ in 0.1 M KCl) were examined by relative viscosity at varying temperatures, with intrinsic viscosity and molar mass determined via Solomon–Ciuta and Mark–Houwink relations. Molar mass degradation followed first-order kinetics, yielding rate constants and degradation lifetimes. Structural parameters, including radius of gyration and second virial coefficient, produced scaling coefficients of 0.62 and 0.15, consistent with perturbed coil conformations in a good solvent. The shape factor confirmed preservation of an ideal random coil structure despite irradiation. Conformational flexibility was further analyzed using theoretical models. Transition state theory (TST) revealed that e-beam radiation lowered molar mass and activation energy but raised activation entropy, implying reduced flexibility alongside enhanced solvent interactions. The freely rotating chain (FRC) model estimated end-to-end distance (R_θ) and characteristic ratio (C_∞), while the worm-like chain (WLC) model quantified persistence length (l_p). Results indicated decreased R_θ, increased l_p, and largely unchanged C_∞, suggesting diminished chain flexibility without significant deviation from ideal coil behavior. Overall, this work provides new insights into Gellan’s scaling laws and flexibility under aerobic low-dose E-beam irradiation, with relevance for bioactive polysaccharide applications. Full article

Nanogels have attracted significant attention in recent years due to their high biocompatibility, controlled release capacity, sensitivity to environmental stimuli, and targeted transport characteristics as drug delivery systems. Chitosan, a natural polysaccharide, is a biopolymer widely used in nanogel formulations due to its positively charged structure, biodegradability, and modifiable functional groups. In this review, the therapeutic applications of chitosan-based nanogels are discussed thoroughly, especially emphasizing in the areas of protein/peptide, antigen, and gene transport. Production methods, chemical modification strategies, transport mechanisms to target cells, and the biological activities of these systems have been evaluated. Chitosan nanogels are promising carrier systems in wide range of areas, including gene therapy, immunotherapy, and the delivery of biological agents, owing to their significant characteristics such as intracellular targeting, endosomal escape, and sustained release. Further studies might enable the translation of these systems into clinical applications. Full article

Polysaccharides have emerged as promising biomaterials for 3D bioprinting due to their inherent biocompatibility, biodegradability, and structural diversity. However, their limited mechanical strength, insufficient bioactivity, and suboptimal printability hinder their direct application in fabricating complex tissue constructs. This review systematically summarizes universal modification strategies to address these challenges by tailoring polysaccharides’ physicochemical and biological properties. We first analyse the fundamental requirements of bioprinting materials, emphasising on the critical role of shear-thinning behaviours, post-printing structural fidelity, and cell-instructive functions. Subsequently, we highlight the advantages and limitations of representative polysaccharides, including chitosan, alginate, and hyaluronic acid. Chemical functionalisation, physical reinforcement, and biological hybridisation are proposed as versatile approaches to synergistically enhance printability, mechanical robustness, and bioactivity to tackle the limitations. Furthermore, dynamic crosslinking mechanisms enabling self-healing and stimuli-responsive behaviours are discussed as emerging solutions for constructing biomimetic architectures. Finally, we outline future directions in balancing material processability with cellular viability and scaling up modified polysaccharides for clinical translation. This review aims to provide a design blueprint for engineering polysaccharide-based bioinks toward next-generation regenerative medicine. Full article

Cartilage damage, particularly in the knee joint, presents a significant challenge in regenerative medicine due to its limited capacity for self-repair. Conventional treatments like microfracture surgery, autologous chondrocyte implantation (ACI), and osteochondral allografts often fall short, particularly in cases of larger defects or degenerative conditions. This has led to a growing interest in tissue engineering approaches that utilize biomaterial scaffolds to support cartilage regeneration. Among the many materials explored, chitosan—a naturally derived polysaccharide—has gained attention for its biocompatibility, biodegradability, and structural resemblance to the extracellular matrix (ECM) of cartilage. Recent advances in scaffold design have focused on modifying chitosan to improve its mechanical properties and enhance its biological performance. These modifications include chemical crosslinking, the incorporation of bioactive molecules, and the development of composite formulations. Such enhancements have allowed chitosan-based scaffolds to better support mesenchymal stem cell (MSC) differentiation into chondrocytes, paving the way for improved regenerative strategies. This review explores the latest progress in chitosan scaffold fabrication, preclinical findings, and the transition toward clinical applications. It also discusses the challenges that need to be addressed, such as mechanical stability, degradation rates, and the successful translation of research into viable therapeutic solutions. Full article

Rice starch, as one of the most abundant and renewable polysaccharide resources in nature, holds great potential for applications in the food, pharmaceutical, and industrial fields due to its wide availability, low cost, and biodegradability. However, its inherent limitations—such as susceptibility to retrogradation and poor emulsifying capacity—have hindered its development into high-value-added products. Emulsion technology presents a promising strategy to overcome these challenges by constructing stable oil–water interfacial systems using various stabilizers. This review highlights recent advances in the functional modification of rice starch through emulsion-based techniques, with a particular focus on four key approaches: polysaccharide–protein complexation, chemical and physical modifications, Pickering emulsions, and microcapsule formation. These strategies significantly improve the emulsifying ability of rice starch, inhibit retrogradation, and expand its potential applications in sustained drug delivery, functional foods, and intelligent packaging. Overall, interfacial engineering of rice starch offers an innovative and effective pathway for its high-value utilization, demonstrating substantial promise for future industrial applications. Full article

Heparin, a widely used polysaccharidic anticoagulant of animal origin, is associated with risks of contamination and adverse effects, notably bleeding and thrombocytopenia. These limitations have prompted interest in alternative sulfated polysaccharides with anticoagulant properties and improved safety profiles. This study explored the anticoagulant potential of two marine bacterial exopolysaccharides (EPS), infernan and diabolican. It assessed whether chemical modifications (depolymerization, oversulfation) could enhance their anticoagulant properties compared to unfractionated and low molecular weight heparins. Native EPS were depolymerized to generate different molecular weights and then chemically oversulfated to increase negative charge density. Anticoagulant activities were evaluated using clotting and thrombin generation assays (TGA). Molecular docking was performed to model interactions with antithrombin and heparin cofactor II. Only highly sulfated derivatives significantly prolonged activated partial thromboplastin time while showing negligible effect on thrombin time and anti-factor Xa activity. They present different structures, and their binding to antithrombin is not achieved via the classic pentasaccharide motif. In TGA, these derivatives inhibited thrombin formation at higher doses than heparin but induced a marked delay in clot generation. Docking analyses supported their ability to bind serpins, albeit with lower specificity than heparin. Their limited anti-Xa activity and non-animal origin position them as promising anticoagulant candidates. Full article

Membrane processes are extensively employed in a range of industrial and food applications. Due to growing environmental concerns and the introduction of regulatory measures, it is imperative to develop innovative membrane materials that can effectively replace petrochemical-based polymers, in line with the principles of a circular economy. The focus of this review is the use of polysaccharides for obtaining films/membranes for food and industrial applications using selected case studies. Besides the polysaccharides extracted from biomass, the valorization of agrifood residues and the use of plants adapted to arid lands (i.e., cactus) to produce polysaccharide films for food packaging is addressed. Moreover, microbial polysaccharides produced using renewable resources present a significant alternative to commercial hydrophilic membranes for gases and ethanol dehydration. To meet industry requirements, the mechanical and barrier properties of the films can be improved by the inclusion of inert impermeable fillers and/or the chemical modification of the polysaccharides. The adsorption of proteins, dyes, and pharmaceutical compounds using a cellulose-based polymer is discussed. Despite their unique characteristics, polysaccharide production costs are still higher than most synthetic polymers. This is a challenge that can be overcome by scaling up the production and by valorizing agro-industrial wastes and by-products to make the application of polysaccharide membranes/films in the food and industry sectors more widespread. Full article

Natural polysaccharides (NPs), as a class of bioactive macromolecules with multitarget synergistic regulatory potential, exhibit significant advantages in diabetes intervention. This review systematically summarizes the core hypoglycemic mechanisms of NPs, covering structure–activity relationships, integration of the gut microbiota–metabolism–immunity axis, and regulation of key signaling pathways. Studies demonstrate that the molecular weight, branch complexity, and chemical modifications of NPs mediate their hypoglycemic activity by influencing bioavailability and target specificity. NPs improve glucose metabolism through multiple pathways: activating insulin signaling, improving insulin resistance (IR), enhancing glycogen synthesis, inhibiting gluconeogenesis, and regulating gut microbiota homeostasis. Additionally, NPs protect pancreatic β-cell function via the nuclear factor E2-related factor 2 (Nrf2)/Antioxidant Response Element (ARE) antioxidant pathway and Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) anti-inflammatory pathway. Clinical application of NPs still requires overcoming challenges such as resolving complex structure–activity relationships and dynamically integrating cross-organ signaling. Future research should focus on integrating multi-omics technologies (e.g., metagenomics, metabolomics) and organoid models to decipher the cross-organ synergistic action networks of NPs, and promote their translation from basic research to clinical applications. Full article

Gelatin, a water-soluble protein, shows unique gellification properties, which determine the active commercial availability of gelatin hydrogels in modern alimentary, cosmetic, and pharmaceutical applications. The traditional sources of gelatin for industrial technologies are pork and bovine skin and bones, which sometimes produce religious and some other restrictions. In recent years, there has been a significant increase in the production of gelatin from alternative sources, such as raw fish materials. Unfortunately, fish gelatin is characterized by weak gelling ability and a decrease in gelation and melting temperature, which are a consequence of the amino acid composition and structural features of fish gelatin. One of the ways to strengthen the natural gelling properties of fish gelatin is the structural modification of gelatin hydrogels by the introduction of polysaccharides of various natural origins. We have studied the association of our laboratory-made fish gelatin with three polysaccharides, namely, κ-carrageenan, alginate, and chitosan, which have distinct chemical structures and gelling capabilities. Structural features of the studied systems were analyzed by small-angle X-ray scattering (SAXS), powder X-ray diffraction (PXRD), and scanning electron microscopy (SEM). We applied computer modeling of molecular interactions between fish gelatin and polysaccharides by means of molecular docking and molecular dynamics approaches. The existence of a correlation between the structure of gelatin-polysaccharide systems and their physicochemical properties was demonstrated by wetting angles (flow angles) and dynamic light scattering (DLS) studies of hydrodynamic sizes and surface ζ-potential. Full article

During plant development or interactions with pathogens, modifications of the plant cell wall occur. Among the enzymes involved, pectinases, particularly polygalacturonases (PGases), play a crucial role in the controlled hydrolysis of cell wall polysaccharides, leading to the formation of oligogalacturonides (OGs). These pectin-derived fragments act as key elicitors of plant defense responses, stimulating innate immunity and enhancing resistance to pathogens by modulating the expression of genes involved in immune responses and inducing the production of defense compounds. OGs are of particular interest for plant protection as a natural alternative to conventional phytosanitary products as they can be obtained through chemical, thermal, or enzymatic degradation of plant biomass. In a sustainable approach, agricultural by-products rich in pectin, such as citrus peels, apple pomace, or sugar beet pulp, offer an eco-friendly and cost-effective alternative for OG production. Thus, the current review aims to (i) update the state of the art about the different methods used to produce OGs, (ii) explore the potential of OGs as bio-based biocontrol molecules, and (iii) examine the relevance of new pectin sources for OG production. Full article

With the increasing attention paid to environmental pollution, paper-based packaging materials have gradually gained favor among people. Paper-based materials are very environmentally friendly and renewable packaging materials. However, the mechanical properties and hydrophobicity of paper-based packaging materials are relatively poor, and they have high requirements for the usage environment and occasions. Therefore, the application of paper-based materials as packaging materials is greatly limited. Polysaccharide polymers, as coatings, have good biocompatibility and are environmentally friendly. They have certain potential in improving the hydrophobicity and mechanical properties of packaging materials. This review article introduces the four kinds of most used polysaccharide polymers, elaborates on their characteristics, and discusses their advantages in enhancing the performance of paper-based packaging materials. It also explores methods such as chemical modification to improve the hydrophobicity of polysaccharide polymers as coatings. Finally, this review discusses the combination of polysaccharide polymer coatings with paper-based packaging materials and provides prospects for the future. Full article

Nanoparticles are small structures that differ in terms of their shape and composition; their high surface-to-volume ratio is responsible for their unique properties that make them perfect mediators for the delivery of substances. Nanoparticles do not only include metallic spheres but also complex polysaccharides capsule viruses or bacterial protein complexes (which can be considered bionanoparticles), which are 1–100 nm in size. Although nanoparticles are most widely studied from medical perspectives, their potential applications are almost limitless. One such promising use of functional nanoparticles is for plant protection against diseases. Although the precise use of nanoparticles decreases the need for the use of other chemical compounds, thanks to their increased product stability and delivery to a target site, the production of nanoparticles is often burdened by large quantities of toxic wastes. This problem can be limited if we apply the bioreactor green synthesis method, which includes the production of nanoparticles with the use of microorganisms. Bacteria can produce nanoparticles internally, externally, by only producing metabolites used for nanoparticle production directly, e.g., polysaccharides or surfactants, or indirectly as reducing agents for metal nanoparticle production. Regardless of the source of the nanoparticles, they can be widely used in processes from plant disease/pathogen detection to disease suppression. The endless variety of materials for nanoparticle production and the possible modifications that nanoparticles can be subjected to makes it impossible to predict how their structures will be used in the future. Nevertheless, in this study, we would like to turn attention to the fact that although nanoparticles are viewed as synthetic structures, they are ever-present in the microbial world and play an important part in intermicrobial interactions. As nanoparticle usefulness has been tested over years of co-evolution, it may be useful to look for potential future directions for this fascinating technology. Full article

Xyloglucan from Tamarindus indica seeds (TISs) is a polysaccharide widely used in the food, biomedical, and pharmaceutical sectors. Nevertheless, the challenge in future research for the food processing industry is to provide adequate knowledge regarding natural product extraction, chemical modifications, interactions, and potential applications according to sustainability issues. The goal of this work was to implement a sustainable method for xyloglucan extraction from TISs at a semi-industrial scale and carry out the characterization of this hydrocolloid, to compare the effect of the technique of decorticating of seeds on the chemical composition and physicochemical properties of xyloglucan. The TISs were decorticated using soaking (DS) and roasting (DR) methods, and, then, the xyloglucan was extracted applying a semi-industrial mechanical separation process. Subsequently, the extraction yield, chemical content, Fourier transform infrared analysis, color, morphology, molecular weight (MW), viscosity, texture, Z potential, particle size, and thermal properties were evaluated. Xyloglucan extraction from TISs at a semi-industrial scale was demonstrated for the first time. The xyloglucan yield by DR (44.04%) was significantly higher (p < 0.05) compared with DS (41.42%), while separation efficiency was similar in both methods (~97%). Significant differences (p < 0.05) in fat, ashes, crude fiber, calcium, total phenolic content, and antioxidant capacity in xyloglucan samples were observed by applying DS and DR. The method of decorticating promoted changes in the MW and particle size of xyloglucan samples, which were reflected in the viscosity, particle size, texture attributes, Z potential, and thermal properties of xyloglucan. These results show that the decorticating method is an important issue to be considered in the resultant chemical and physicochemical properties of xyloglucan extracted from tamarind seeds, for suitable applications of the xyloglucan in the food processing and pharmaceutical industries. Full article

Gum Arabic (GA), or acacia gum, refers to the dried exudate produced by certain Acacia trees. GA is composed mainly of a mixture of polysaccharides and glycoproteins, with proportions that can slightly differ from one species to another. It is commonly utilized in the food and pharmaceutical industries as a stabilizer or an emulsifier owing to its biocompatibility, hydrophilicity, and antibacterial properties. In addition, GA can be manipulated as it possesses many functional groups that can be used in grafting, cross-linking, or chemical modifications to add a new feature to the developed material. In this review, we highlight recent GA-based formulations, including nanoparticles, hydrogels, nanofibers, membranes, or scaffolds, and their possible applications in tissue regeneration, cancer therapy, wound healing, biosensing, bioimaging, food packaging, and antimicrobial and antifouling membranes. Full article

Thermal modification improves the properties of wood, especially its stability and durability. We thermally treated spruce wood with the Thermowood process at three temperatures (160 °C, 180 °C, and 210 °C) and subjected it to accelerated aging in wet mode. We evaluated the chemical composition (wet chemistry, infrared spectroscopy), color, surface morphology, and wetting of the wood surface with water. Thermal treatment caused a significant decrease in hemicelluloses (up to 72.39% at a temperature of 210 °C), which initiated an increase in the content of more resistant wood components—cellulose and lignin. With accelerated aging, the hemicellulose content decreased by another 5%. The most significant differences between the infrared spectra of thermally modified wood before and after exposure to accelerated aging were in the absorption bands of lignin (1509 and 1596 cm⁻¹) and in the region of carbonyl groups between 1800 and 1630 cm⁻¹. Thermal treatment also caused a change in the color of the wood to dark brown; the overall color difference ΔE increased several times. The thermal-induced shortening of polysaccharide fibers and reduction in their width were even more manifested during accelerated aging. This work contains new knowledge about the properties critical for the reuse of thermally modified wood after accelerated aging, simulating the end of its life cycle. Full article