Polysaccharides, Volume 6, Issue 4 (December 2025) – 14 articles

Cathepsin S (Cat S) is a cysteine protease involved in several human diseases (i.e., autoimmune, inflammatory and cardiovascular disorders, cancer, and psoriasis) and is an important target in drug development. Emerging evidence highlights the potential of inhibiting Cat S by glycosaminoglycans, particularly chondroitin sulfates (CSs), as a promising therapeutic strategy. Given the limited and heterogeneous GAG materials from animal sources, a series of synthetic biotinylated non- or sulfated chondroitin oligomers were synthesized and assessed for their ability to inhibit Cat S. The biotinylated disaccharide C4S displayed in vitro potent inhibitory activity toward Cat S with IC₅₀ value in the micromolar range and showed selectivity over cathepsins K and L. Molecular modeling studies suggested that only C4S dp2 but not C6S, C4,6S or non-sulfated chondroitin binds selectively to the active site of Cat S. In addition, a synthetic multivalent C4S dp2 glycosylated BSA was shown to be more efficient towards Cat S inhibition (nanomolar range) than the monovalent parent C4S dp2. Our findings also indicated that this new neoglycoconjugate displayed selectivity for Cat S vs. cysteine cathepsins expressed by differentiated THP-1 cells. This study reports a new approach for designing selective and potent inhibitors of Cat S using multivalent C4S derivatives as a molecular scaffold. Full article

The dragon fruit (Selenicereus sp.) peel is a viable plant source for the extraction of polysaccharides such as pectin, the demand for which has increased significantly in the food and pharmaceutical industries. In Nayarit, Mexico, the Queen Purple variety of dragon fruit (Selenicereus cf. guatemalensis) is commonly cultivated. The peel is typically discarded, while only the pulp is utilized for direct consumption or processed into derivative products. The objective of this study was to characterize the properties of pectin extracted from the peel of dragon fruit (Selenicereus cf. guatemalensis ‘Queen Purple’). The yield, molecular weight, anhydrouronic acid content, betalain content, antioxidant capacity, and phenolic compounds were determined using gravimetric, volumetric, spectrophotometric, and colorimetric techniques, among others. Furthermore, the functional groups and degree of esterification of the pectin were identified using Fourier-transform infrared spectroscopy. The pectin presented a yield of 12.8%, esterification degree of 49.85%, molecular weight of 645 kDa, anhydrouronic acid, phenolic acid and betalain content of 98.27%, 195.7 mg EAG/100 gDW and 4.26 mg/100 gDW respectively and an antioxidant capacity of 149.6, 192.76 and 20.5 mg EAA/100 gDW by the DPPH, ABTS and FRAP methods respectively, classified as high-purity, low-methoxyl, intermediate-molecular-weight, with an important betalain content and antioxidant capacity. Based on these findings, the extracted pectin complies with the Food and Agriculture Organization specifications and shows promise as a functional ingredient in the food industry. Full article

The SCOBY (Symbiotic Culture of Bacteria and Yeast) is a microbial consortium composed of a diverse range of bacteria and yeasts that coexist symbiotically. The most commonly identified microorganisms include Gluconobacter, Acetobacte, Saccharomyces and Zygosaccharomyces. Its primary objective is to utilize sucrose as a substrate. SCOBY requires specific conditions for its multiplication, such as temperature, pH, and a suitable carbon source. Through its microbial dynamics and proper management, this consortium develops functional properties that are beneficial to health. This microbial consortium has been the subject of numerous studies due to the wide range of benefits it can offer through fermentation-derived products. Among the most frequently mentioned are organic acids, phenolic compounds, and a high concentration of probiotics. Originally, the SCOBY was used as a started culture in the production of the beverage “Kombucha”. However, due to the growing public interest, its use has diversified into fruit-based, dairy-based, and cereal-based beverages. Furthermore, its application has expanded to unconventional substrates. Its potential uses in other fields, such as medicine, as well as its antimicrobial activity, should also be noted. Full article

The carob tree (Ceratonia siliqua L.) is receiving growing attention for its agro-industrial potential, particularly due to its seeds, which are the source of locust bean gum (LBG), a galactomannan-rich polysaccharide with wide applications in food and pharmaceutical industries. Efficient dehusking of carob seeds is critical to maximize LBG purity and yield, yet current industrial methods pose environmental concerns and lack robust quality control tools. In this study, we demonstrate the use of Diffuse Reflectance Spectroscopy (DRS) and Kubelka–Munk (KM) modeling as a rapid, non-destructive technique to assess dehusking efficiency. By combining spectral data from four complementary spectrometers (450–1800 nm), we identified key reflectance and absorbance features capable of distinguishing raw, industrially treated, and laboratory-dehusked seeds. Notably, our laboratory-treated seeds exhibited a considerably lower reflectance in the NIR plateau (800–1400 nm) compared to raw and industry-treated seeds, and their KM-reconstructed skin showed enhanced absorption bands at 960, 1200, and 1400 nm, consistent with more complete husk removal and improved light penetration. Principal Component Analysis revealed tighter clustering and lower variability in lab-processed seeds, indicating superior process reproducibility. These results establish DRS as a scalable, green analytical tool to support quality control and optimization in carob processing. Full article

Wheat is often used as a raw material in the brewing of special styles of beer. Hydrocolloids naturally present in wheat are called pentosans. They constitute approximately 2% of wheat flour. Arabinoxylans (pentosanes) and β-glucan are common compounds in wheat and are mostly found in the cell wall. Hydrocolloids are commonly used to retain moisture in bread and baked goods. Besides the moisture content, they affect the texture and retrogradation enthalpy of starch molecules. In the baking industry, they can be useful and improve the dough properties, but in the brewing industry, they are commonly designated as problematic compounds. Namely, to a certain extent, they can improve the foam stability; however, they can hinder the filtration process. This review paper aims to give an overview of non-starch compounds and their properties and to emphasize the significance of these macromolecules in the malting and brewing industries, especially in wheat varieties. The objective of this review is to gather information by searching different databases with scientific papers to broaden knowledge on arabinoxylans and β-glucans in brewing. Full article

Resveratrol (RES), a naturally occurring polyphenolic compound with well-documented anticancer potential, is limited in clinical application due to its poor aqueous solubility and low bioavailability. This study aimed to develop RES-loaded liposomes coated sequentially with chitosan (CS) and hyaluronic acid-chitosan (HA) (RES-HA-CS-Lip) to enhance RES stability, delivery, and anticancer efficacy in breast cancer cells. HA-CS-coated liposomes were prepared using a thin-film hydration technique. Their physicochemical characteristics were thoroughly investigated through dynamic light scattering, transmission electron microscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. The optimized RES-HA-CS-Lip exhibited spherical morphology with an average particle size of 212 nm, a narrow polydispersity index (<0.4), a zeta potential of +9.04 ± 1.0 mV, and high entrapment efficiency of 82.16%. Stability studies demonstrated superior retention of size, surface charge, and encapsulation efficiency over 28 days at both 4 °C and 25 °C. In vitro release profiles at physiological and acidic pH revealed sustained drug release, with enhanced release under acidic conditions mimicking the tumor microenvironment. Antioxidant activity, assessed via DPPH and ABTS radical-scavenging assays, indicated that RES retained its radical-scavenging potential upon encapsulation. Cytotoxicity assays demonstrated markedly improved anticancer activity against MCF-7 breast cancer cells, with an IC₅₀ of 13.08 μg/mL at 48 h, while maintaining high biocompatibility toward normal HaCaT keratinocytes. RES-HA-CS-Lip demonstrated excellent stability against degradation and aggregation. Overall, these findings highlight HA-CS-coated liposomes as a promising polysaccharide-based nanocarrier that enhances stability, bioactivity, and therapeutic efficacy of RES, representing a potential strategy for targeted breast cancer therapy. Full article

This study investigated the effects of homolactic fermentation on the rheological, viscoelastic, and starch structural properties of quinoa–chickpea flour-based beverages. Three formulations with increasing proportions of chickpea flour (10, 25, and 50%) were fermented for 10 h with Lactobacillus acidophilus LA-5. Apparent viscosity, deformation capacity, storage modulus (G′), and pasting behavior were measured along with FTIR-based analysis of the starch molecular structure. All fermented samples reached pH values < 4.5 and exhibited improved rheological properties with significant increases in viscosity and storage modulus (G′), particularly in the 50:50 blend. These enhancements were attributed to the synergistic effects of homolactic fermentation and inherent properties of chickpea starch, particularly its high amylose content, large granule size, and long amylopectin chains. FTIR analysis revealed that the short-range molecular order of starches was preserved after fermentation in all beverages, except for the 50:50 blend, as evidenced by the increased degree of order (DO) and double helix (DD) ratios. Overall, these findings demonstrate that integrating chickpea flour and controlled homolactic fermentation is an effective strategy for tailoring the viscosity and stability of plant-based probiotic beverages, providing a theoretical basis for the development of clean-label and functional fermented plant-based systems. Full article

The increasing demand for sustainable alternatives to non-biodegradable plastic packaging is driving the development of active packaging based on biopolymers such as methylcellulose. In this study, innovative methylcellulose nanocomposite films incorporating zein nanoparticles loaded with propolis and curcumin were developed for active packaging applications. The zein nanoparticles revealed excellent physicochemical properties, with a zeta potential above 30 mV, suggesting adequate stability. Transmission electron microscopy confirmed nanoparticles containing curcumin and propolis with uniform sizes ranging from approximately 130 to 140 nm with low polydispersity. Release studies revealed that approximately 25% of the curcumin and 35% of the propolis were released from the nanoparticles within 24 h. The release mechanism was best described by the Korsmeyer–Peppas model, suggesting a sustained release profile. The nanoparticles reduced the hydrophobicity and rigidity of the films, as evidenced by a lower elastic modulus and higher percentage elongation, thereby suggesting greater flexibility. Fourier Transform Infrared Spectroscopy (FTIR) analysis revealed the incorporation of bioactive compounds in the polymer matrix. Differential scanning calorimetry (DSC) revealed the thermal parameters of the synthesized films. Furthermore, the films exhibited antibacterial and antioxidant activities, making them highly suitable for use as biodegradable active packaging. Full article

Chitosan-based hydrogels are used in the adsorption of pharmaceutical compounds from water. The adsorption process of diclofenac and naproxen on chitosan hydrogels cross-linked with glutaraldehyde has been studied theoretically and experimentally. According to the thermodynamic properties, the adsorption processes were spontaneous and endothermic, due to the negative values of Gibbs free energy, and the enthalpies of formation were positive. Furthermore, the different systems were studied by electrostatic potential maps, where the functional groups (amino and hydroxyl) represented the active sites of the hydrogel. The maximum adsorption capacity obtained for diclofenac and naproxen was 108.85 and 97.22 mg/g, respectively, at a temperature of 308.15 K. On the other hand, the adsorbent was characterized by FTIR (Fourier Transform Infrared Spectroscopy) and XRD (X-ray Diffraction) before and after the adsorption of the drugs to confirm the binding of the adsorbates on the surface of the material. Full article

Fucoidan B (FucB) is a sulfated polysaccharide with recognized biological activity. In this study, FucB was chemically modified through redox conjugation with gallic acid (GA) to obtain FucB-GA, aiming to enhance its antioxidant properties. Structural characterization using FTIR, NMR, and electrophoresis confirmed the successful covalent binding of GA to FucB without major structural degradation. The conjugation increased the phenolic content and reduced crystallinity, as shown by XRD and SEM, indicating greater amorphous character, which can favor biological applications. Thermogravimetric analysis demonstrated enhanced thermal stability in FucB-GA. Antioxidant activity was evaluated through various in vitro assays. FucB-GA showed superoxide radical scavenging activity of 91.96%, copper chelating capacity of 43.2%, antioxidant capacity of 37 mg AEE/g, and reducing power of 94.22%, significantly higher results than FucB, while no sample chelated iron. Under the conditions analyzed, gallic acid alone showed minimal or no activity in most assays. These results suggest that conjugation with GA increases the antioxidant potential of FucB, while also improving the activity and bioavailability of GA, likely due to the increase in electron-donating and metal-binding groups. Overall, the study supports the development of FucB-GA as a promising antioxidant compound for pharmaceutical or nutraceutical applications. Full article

The precipitation of cellulose and polyacrylonitrile and its copolymer (PAN) solutions is a well-known process that has been extensively described in numerous studies. It is suggested that “soft” precipitants (aqueous solutions of solvent, alcohols) be used in place of “rigid” ones (water) to control the rate at which solutions precipitate. Diffusion processes can also be controlled by lowering the temperature of the interacting system’s constituent parts. The appearance and structure of the resulting fibers (films) are directly correlated with the rate of coagulation. Adding a composite additive to the solution is an unusual method of altering the rate of polymer phase release. The introduced additive should dissolve in a common solvent, which will ensure the competition of precipitation between the polymer phases. It is shown that using optical methods it is possible to trace the evolution of the polymer phase precipitation and the formed morphology. For 12% solutions of cellulose, PAN and mixed systems in N-methylmorpholine-N-oxide (NMMO) the kinetics of the movement of isoconcentration planes was traced and the growth rates of the precipitated polymer zone were estimated. The introduction of PAN additives into cellulose enables the influence of diffusion processes and minimizes the formation of finger-like defects (vacuoles). When the PAN content in the system is 30% or more, the formation of defects in the precipitated solution is significantly suppressed, which is crucial for achieving a uniform morphology. Full article

As the demand for chitin grows, new chitin sources with unique physicochemical properties are required. Abundant biofouling species, such as amphipods and hydroids, have chitinous skeletal systems that can be utilized for chitin production. However, little is known about these chitin sources. This study investigated the viability of amphipods (Jassa sp.) and hydroids (Coryne sp.) obtained from aquaculture biofouling assemblages as novel sources of chitin. Chitin was extracted from these sources and characterized in terms of its degree of acetylation (DA), crystallinity index (CrI), molecular weight (MW), thermal stability, and surface morphology. Physiochemical characteristics where then compared against commercially available shrimp chitin. Results show that a 32.75% chitin yield can be obtained from hydroids. The percentage DA for amphipod (AC) and hydroid (HC) chitin is 58.4–59.2% and 64.8–66.7%, respectively. AC is characterized as α-chitin with a low molecular weight (MW), while HC is medium-MW β-chitin. This finding is significant because it shows hydroids to be a new source of rare β-chitin. In addition, AC has higher thermal stability than HC. AC and HC greatly differ in terms of surface morphology. Therefore, the chitin biomaterials extracted from amphipods and hydroids have different but favorable properties that can be used for diverse applications. Full article

In this work, redox-responsive chitosan derivatives were prepared by crosslinking with disulfide-bridged dicarboxylic acids. Taking into account that structural variations in diacids can lead to significant differences in properties, especially swelling capacity, this study aimed to evaluate the impact of increasing alkyl chain length and hydrophobicity. Two dicarboxylic acids of different hydrophobic character and chain length were used: dithiodiglycolic acid (DTGA) and dithiopropionic acid (DTPA). The resulting materials were fully characterized. Despite their structural similarity, the derivatives exhibited distinct behaviors: DTGA derivatives formed stable hydrogels, whereas DTPA ones remained compact upon contact with water. These results were confirmed by swelling measurements and oscillatory rheology. The EDC:COOH molar ratio was also evaluated, revealing a strong effect on the degree of crosslinking. Moreover, DTGA systems prepared at a 1:1 ratio showed significantly higher swelling than those synthesized at 3:1. Regarding redox responsiveness, it was assessed by quantifying thiol content before and after reduction with sodium borohydride, and reversibility was assessed through reduction–oxidation cycles. Finally, preliminary experiments evaluated the materials’ ability to incorporate benzalkonium chloride as a model biocide, and their release was tested in the presence of thiosulfate-reducing bacteria, providing initial insight into their behavior in redox-responsive delivery systems. Full article