Dynamic extracellular polymeric substance component succession primes cyanobacterial metabolism for distinct bloom stages.

Ultrasonic-assisted preparation, characteristics and activity of Goji berry polysaccharide

Structural characterization and anti-aging mechanism of Codonopsis pilosula polysaccharides.

Structure and gene cluster of the capsular polysaccharide of Acinetobacter baumannii K223.

Structural validation and immunogenic characterization of Streptococcus pneumoniae serotype 22A capsular polysaccharide relative to serotype 22F.

Evaluation of the Relative Ordered Structure of Polysaccharide: a case study on polysaccharide characterization from Gymnadenia conopsea

Ultrasound-assisted extraction optimization of Fructus Tribuli polysaccharides: How stir-frying processing alters structures and enhances antihypertensive efficacy.

Solution-state two-dimensional (2D) 1H-13C HSQC NMR is a powerful tool for polysaccharide structure elucidation but often suffers from limited sensitivity and broad peaks due to the low natural abundance of 13C and poor digital resolution of the indirect dimension, respectively, as well as the typically low concentration and high viscosity of polysaccharide solutions. It is therefore pivotal to improve the resolution of 2D 1H-13C HSQC spectra for accurate peak picking and assignment, particularly in the indirect 13C dimension. In this study, we developed an algorithm that combines first derivative processing with a novel logarithmic cosine transformation (FDP-LCT) to convert 2D 1H-13C HSQC spectra into local-resolution-enhanced images resembling a dark forest of straight, densely standing trees. These images revealed sharpened spectral features and enabled extraction of precise 1H and 13C chemical shifts, as demonstrated using per-O-ethylated kappa- and iota-carrageenans, two sulfated galactans differing only by a single substitution at the O-2 position of anhydrogalactose. In conclusion, this approach provides an effective post-acquisition strategy for enhancing digital resolution in 2D HSQC spectra and improving the structural analysis of closely related complex polysaccharides.

Effects of sulfated Tricholoma mongolum Imai polysaccharides on scallop mince gel properties: Mechanisms and structural analysis.

Development of biodegradable alginate films with Aloe Vera and quince seed mucilage: Physical, chemical, and biological properties.

Molecular dynamics (MD) simulations of three α-glucans─amylose, dextran, and pullulan─were performed in explicit solvent to investigate how differences in their glycosidic linkages influence molecular conformation and solvation dynamics, and to assess the performance of three major force fields (FFs): CHARMM36, GLYCAM06, and OPLS-AA. Structural analysis revealed that amylose adopts a more extended and constrained conformation owing to its α-(1 → 4) linkages, whereas dextran and pullulan exhibit more collapsed structures. Differences in linkage chemistry also influenced the organization of surrounding water, with this effect more pronounced in CHARMM than in GLYCAM or OPLS. Dextran formed more stable hydrogen bonds with water than amylose or pullulan. Although glucan-water nonbonded interactions were energetically more favorable in GLYCAM and OPLS, these FFs also predicted stronger nonpolar interactions that promoted more compact glucan conformations. Overall, the results indicate that glucan-glucan interactions contribute comparably to glucan-water interactions in determining polysaccharide structure. These insights clarify molecular determinants of glucan solubility and hydration and provide a basis for designing glucan-based materials with tunable properties.

Brewer’s spent grain (BSG) is an abundant lignocellulosic by-product whose valorization can support circular bioeconomy strategies. This study evaluated BSG bioconversion by Aspergillus oryzae ATCC 10124 under solid-state fermentation (SSF) to produce lignocellulolytic enzymes and release second-generation (2G) sugars relevant to biorefinery applications. SSF was monitored over 0–10 days, and FPase, endo-cellulase, β-glucosidase, xylanase, mannanase, amylase, and ligninolytic enzyme activities were quantified. Enzymatic crude extracts were further assessed in SDS-PAGE analysis. Glucose, cellobiose, xylose and arabinose release and consumption were tracked throughout fermentation, and substrate transformation was supported by FTIR. The secretome exhibited a predominantly hydrolytic profile, with maximal hemicellulolytic and cellulolytic activity around days 2–4, as well as sustained amylase activity. Ligninolytic activity was not detected. Sugar profiles indicated rapid early hydrolysis of glucose, followed by progressive pentose release. The stabilization and decline were consistent with fungal uptake. Changes in the carbohydrate fingerprint and SDS–PAGE banding supported structural polysaccharide remodeling and hydrolytic protein secretion. Thus, this SSF platform confirmed certain potential for low-cost cellulolytic and hemicellulolytic enzyme generation. However, because sugar accumulation was temporary and followed by consumption, this system is best interpreted as a biological pretreatment and enzyme-generation step that supports subsequent downstream valorization.

Accurate monosaccharide composition analysis was a prerequisite for studying the structure and function of polysaccharides. This study evaluated three one-step hydrolysis methods (H2SO4, trifluoroacetic acid (TFA), and Driselase) on polysaccharides with varying uronic acid contents and developed an enzyme--acid hydrolysis protocol for acidic polysaccharides. Results demonstrated that neutral tamarind seed polysaccharide (TSP) was effectively hydrolyzed by H2SO4/TFA with hydrolysis yields exceeding 97%. However, acidic polysaccharides, including peach gum polysaccharide (PGP), phyllanthus emblica polysaccharide (PEP), and passion fruit pectin (PFP), showed low hydrolysis yields with one-step methods. A Driselase-H2SO4 hydrolysis strategy was then established involving Driselase pretreatment, followed by H2SO4 hydrolysis at optimized conditions (0.5-2.0 M, 60-90 min). This protocol increased the hydrolysis yields of PGP, PEP, and PFP to 97.41%, 86.17%, and 87.06%, respectively, with high repeatability and precision. These results were significantly higher than those from one-step hydrolysis methods, effectively improving the accuracy of the monosaccharide composition analysis for acidic polysaccharides.

Infection from Streptococcus pneumoniae can lead to serious complications, such as meningitis and pneumonia, in children under 2 years of age, older adults, and immunocompromised populations. Conjugate vaccines against the pathogen have been licensed for the prevention of invasive pneumococcal disease. Conjugate vaccine development is an involved process demanding extensive characterization of both the polysaccharide (PS) and protein (Pr) moieties in complex structures. One powerful tool in our analytical tool kit that can shed light on various analytical attributes of conjugate vaccines, such as molecular weight and composition and conjugation efficiency, is the size-exclusion chromatography-multi-angle light scattering detector (SEC-MALS) technique. Herein, we demonstrate the applicability of the SEC-MALS approach for pneumococcal conjugate vaccine product characterization. Capsular polysaccharides for serotypes (STs) 1, 3, 5, 10 A, 18 C, 24 F, and 33 F conjugated to rCRM197 carrier protein were chosen for this study. The technique was very straightforward, with a high degree of accuracy (>90% based on standards) and repeatability (<2% RSD) for conjugate molar mass measurements. In addition, leveraging the capability of SEC-MALS for compositional analysis, we were able to get detailed information on the molecular assembly and conformation of the conjugates and further tweak the conjugation process to yield conjugates of a desired molar mass. Thus, this study highlights the usefulness of the SEC-MALS technique for in-depth conjugate vaccine biophysical characterization, which is critical for achieving optimal product attributes, driving manufacturing consistency and vaccine potency.

Structural studies on cell wall and matrix polysaccharides of Micrococcus luteus HB3.2.1.

This article systematically reviews the effects of various processing methods on the physicochemical properties, structure and biological activities of polysaccharides. Studies have demonstrated that processing methods can significantly alter the sugar content, molecular weight, monosaccharide composition, and structural characteristics of polysaccharides, thereby influencing their biological activities. Processing techniques in Traditional Chinese Medicine (TCM), such as steaming, brewing, and stewing, have been shown to reduce the sugar content of polysaccharides. In contrast, factors such as alcohol, cellulase, and high temperature are known to regulate the molecular weight of polysaccharides. Different processing methods significantly affect the monosaccharide composition and molar ratio, which are closely related to the Maillard reaction. Furthermore, the polysaccharide chain structure undergoes considerable alterations during processing, which in turn influences its biological activities. Several studies have reported that processing methods can enhance the biological activities of polysaccharides, including antioxidant, immune-regulatory, prebiotic, anti-inflammatory, and antitumor properties. However, TCM processing methods are not without limitations and require further exploration of the “process-structure-mechanism”chain to provide theoretical and technical support for their modernization. Current studies lack standardized processing protocols and in-depth mechanistic evidence in vivo, hindering clinical translation. Future work should optimize the integration of traditional processing and green extraction, clarify structure-activity relationships, and validate efficacy and safety in clinical settings for rational application. • Physicochemical properties of Polysaccharides were altered by TCMs processing methods, then enhancing their bioactivity. • Heating and auxiliary materials were considered as key factors of polysaccharide properties and activities in TCMs processing. • The potential mechanisms (Maillard reaction, structural isomerization, aggregation) were hypothesized in TCMs processing. • Future research focus: structure-activity correlations, standardized methods, and control of potential toxic by-products, etc.

During the extraction process of Houttuynia cordata polysaccharides (HCPs), different extraction methods significantly influence their structural characteristics, thereby influencing their biological activities. This study compared the structural differences of HCPs prepared by five extraction methods (hot water, ultrasound-assisted, enzymatic, acid, and alkaline extraction) and evaluated in vitro antioxidant and α-glucosidase inhibitory activities of HCPs. An orthogonal partial least squares-discriminant analysis (OPLS-DA) model was applied to analyze the relationship between extraction techniques and structural characteristics of HCPs. The results revealed that distinct extraction methods primarily influenced molecular weight, degree of methylation (DM), and galacturonic acid (GalA) content of HCPs. Ultrasound, enzyme, and alkali treatments all disrupted the GalA structure, increased the molar ratio of neutral sugars, and reduced both molecular weight and DM. Notably, alkali-extracted HCPs exhibited the lowest molar ratio of GalA, the most significant reductions in DM (6.43%) and molecular weight (119kDa). In contrast, acid extraction preserved relatively high DM (45.08%) and molecular weight (236kDa). Surface morphology analysis further confirmed that alkali- and ultrasound-treated HCPs exhibited more fragmented structures. Functionally, alkali-extracted HCPs exhibited the highest antioxidant capacity (IC50 = 0.26mg/mL for DPPH and 0.17mg/mL for ABTS, FRAP: 0.92mmol TE/g DW) and α-glucosidase inhibitory activity (IC50 = 0.097mg/mL). Therefore, alkaline extraction is an efficient strategy for enhancing the functional properties of HCPs. This study elucidates the relationships among extraction methods, polysaccharide structure, and bioactivity, providing valuable guidance for the preparation of HCPs with specific structural and functional characteristics. PRACTICAL APPLICATIONS: This study employed five extraction methods (hot water, ultrasound-assisted, enzymatic, acid, and alkaline extraction) to prepare HCPs, and systematically compared their structural characteristics, in vitro antioxidant activity and α-glucosidase inhibitory activity. The relationship between extraction methods and structure of HCPs was elucidated, providing guidance for the targeted preparation of HCPs with specific structural features and enhanced bioactivity.

Pichia anomala enhances the growth and lactic acid production of Leuconostoc citreum: Synergistic improvement for sweet sorghum silage quality.

Current emerging trends in structure and bioactivities of acidic and alkali-extracted polysaccharides: A review

Extraction, isolation, purification, structural characterization, and activity of two homogeneous polysaccharides from the pericarp and kernel of Gymnocladus chinensis Baill.