Search Results (123)

Calcium-induced polysaccharide hydrogels have attracted growing interest in food science because of their mild gelation conditions, tunable structures, and compatibility with food-grade formulation. This review focuses on edible Ca²⁺-mediated polysaccharide hydrogels and related composite networks, focusing on alginate, low-methoxyl pectin, gellan gum, and carrageenan. Rather than treating all calcium-containing polysaccharide materials as well-defined complexes, we distinguish direct coordination, ionic bridging, charge screening, helix stabilization, and composite-assisted network regulation. Current evidence indicates that Ca²⁺-mediated assembly is governed by polysaccharide fine structure, calcium-release behavior, pH, ionic strength, and processing conditions, thereby determining crosslinking density, digestibility gel strength, water distribution, rheological properties, release behavior, and texture-related functionality. For texture-modified foods for older adults, these hydrogels may provide a useful material basis for designing swallowing-friendly matrices, sustained nutrient-delivery systems, and soft composite foods. However, available evidence is still largely derived from model gels, in vitro characterization, and static digestion models, while validation in real food matrices, dynamic gastrointestinal conditions, oral processing, sensory acceptance, and older-adult populations remains limited. Future studies should establish structure–function–population evidence chains linking molecular assembly to reliable geriatric food performance. Full article

The valorization of agro-industrial byproducts is attracting attention due to its potential to support circular bioeconomy development in food systems. Dragon fruit (Selenicereus spp.) peel, representing approximately one-third of total fruit mass, is an underutilized biomass that is high in pectin content. Unlike standardized commercial citrus and apple pectins, pectin from dragon fruit peel exhibit variability in their galacturonic acid content, degree of esterification, molecular weight, and rhamnogalacturonan-I branching structure, which are dependent on how the pectin is extracted. These structural attributes influence the solubility, rheological properties, gelation mechanisms, emulsifying capacity, and water-holding properties. There is emerging evidence that rhamnogalacturonan-I-enriched fractions promote the growth of beneficial microorganisms and may also increase the in vitro production of short-chain fatty acid, thereby exhibiting potential prebiotic activity. In addition, low methoxyl pectin has been shown to provide excellent properties for the calcium-mediated encapsulation of probiotics, as well as for pH-sensitive release in the gastrointestinal tract, thus supporting the synbiotic concept. The purpose of the current paper is to provide an overview of recent findings related to extraction technologies, structural characterization, structure–function relationship, fermentation behavior, potential delivery of probiotics, and the regulatory requirements for using dragon fruit peel pectin in the development of functional foods. Full article

Hydrocolloids comprise a diverse class of high-molecular-weight polymeric carbohydrates associated with a wide range of physicochemical and functional properties. This review provides an integrated analysis of natural hydrocolloids derived from algal (agar, alginate, carrageenan, fucoidan, laminarin, and ulvan), animal (chitin, chitosan, chondroitin sulfate, dermatan sulfate, keratan sulfate, heparin, heparan sulfate, glycogen, and hyaluronan), and plant (pectin, starch, and locust bean gum) sources, together with semisynthetic cellulose-based derivatives. Emphasis is placed on the relationship between molecular structure, charge density, sulfation patter, and branching degree, and how these parameters modulate hydration, gelation, and rheological behavior. Comparative analyses are presented, establishing structure–function interactions that link molecular characteristics to functional properties, including thickening, gelling, emulsifying, stabilizing, film-forming, and controlled-release capacities. The review also discusses the biological activities and application potential of these hydrocolloids in pharmaceutical, biomedical, and advanced material systems. In addition, emerging modification strategies, including chemical functionalization, crosslinking, and nanostructuring are discussed as tools to adjust their action and diversify their application range. Special attention is given to structure–rheology–gelation relationships and to the influence of molecular organization on mechanical strength, stability, and delivery performance. Current challenges associated with scalability, processability, reproducibility, and long-term functional stability are also critically discussed. Overall, this review provides a comprehensive structure–function perspective on hydrocolloids as sustainable and multifunctional polymeric materials, supporting their rational design and continued development in pharmaceutical sciences, biomedical engineering, and advanced material applications. Full article

Maize is one of the most widely cultivated crops worldwide and is extensively used for animal feed and industrial applications. Plant height (PH) and ear height (EH) are critical determinants of lodging resistance and tolerance to high planting density, and coordinated regulation of these traits is essential for yield improvement. In this study, 479 maize inbred lines from Northeast and North China were genotyped using 7861 single-nucleotide polymorphism (SNP) markers to perform a genome-wide association study (GWAS). After controlling for population structure and relatedness, the mixed linear model (MLM) identified 20 loci significantly associated with PH on chromosomes 2, 4, 5, 6, 7, and 8, and 8 loci associated with EH on chromosomes 2, 3, 4, and 7. A total of 23 candidate genes were identified, including PLATZ8, pectin methylesterase 36, and leucine-rich repeat extensin 14. Gene Ontology (GO) enrichment analysis revealed significant enrichment in biological and molecular functions such as DNA binding, pectinesterase activity, zinc ion binding, ATP binding, and uniporter activity. Bioinformatic characterization of the two most likely candidate genes, Zm00001d002726 and Zm00001d015394, showed that both possess a typical compact four-exon structure. Functional prediction indicated that Zm00001d002726 encodes a pectinesterase/pectinase, potentially regulating cell elongation through pectin degradation and remodeling of the cell wall. Pectinesterase activity may influence PH and EH by mediating pectin demethylation within the cell wall. In contrast, Zm00001d015394 encodes a PLATZ family transcription factor that may regulate downstream gene expression through DNA-binding activity. These findings provide insight into the genetic architecture and potential molecular mechanisms underlying PH and EH in maize and offer a foundation for future breeding efforts. Full article

Background: Fruit texture is a major component of plum quality, affecting both consumer acceptance and postharvest behavior. Pectin methylesterases (PMEs) play important roles in cell-wall pectin modification and are therefore likely to contribute to plum fruit texture development and ripening-associated softening. However, the PME gene family has not yet been comprehensively investigated in plum (Prunus salicina L.). Methods: In the present study, a chromosome-level plum genome was used to survey this gene family at the whole-genome scale. Phylogenetic relationships, chromosomal positions, exon–intron organization, conserved motifs, domain architectures, gene duplication, and cis-elements were analyzed. Four flesh texture traits were measured in 55 plum accessions to characterize texture variation and select two representative cultivars with contrasting flesh textures for further molecular analysis. Based on the clustering results, ‘WSCL’ and ‘FR’ were selected for expression profiling during fruit development and subsequent correlation analysis with texture traits. Results: A total of 46 PsPME genes were identified. Phylogenetic analysis classified them into four major subgroups. Structural analyses indicated an overall conserved family framework, although noticeable variation was retained among individual members. Dispersed duplication made the largest contribution to family expansion, and most duplicated pairs appeared to have evolved under purifying selection. Correlation analysis showed that PsPME20, PsPME22, and PsPME25 were significantly negatively correlated with flesh firmness, while PsPME20 was additionally linked to flesh compactness and flesh fragility. Conclusions: Overall, this study clarifies the structural and evolutionary characteristics of the PsPME family and identifies candidate genes that may contribute to texture differences in plum, offering a basis for future functional studies and breeding programs. Full article

This study investigates the extraction of pectic polysaccharides from rapeseed meal (RSM) using both conventional and enzyme-assisted techniques, and the obtained pectic polysaccharide fractions will be used later to produce prebiotic pectic oligosaccharides (POS). A two-step process was developed, involving enzymatic treatment with Alcalase^® 2.4 L for 2 h and Cellic^® CTec3 HS preparations for 24 h, followed by ammonium oxalate extraction, which effectively isolated two pectic polysaccharide-enriched fractions: PP-EAE (first step) and the resulting Ca-bound pectic polysaccharides fraction (CaPP-EAE) (second step). Both fractions exhibited a bimodal molecular weight profile, indicative of the presence of long-chain polysaccharides alongside oligosaccharides. CaPP-EAE compositional analysis revealed that the fraction contained 56.8% galacturonic acid (GalA), low methyl-esterified (LM) pectins with 53.2% homogalacturonan (HG) and 30.2% rhamnogalacturonan I (RG-I) domains, featuring side chains of arabinan, arabinogalactan, and galactan. Subsequent enzymatic treatment with 0.5% (v/v) of Pectinex^® Ultra Passover for 30 min transformed these fragments into a mixture of short-chain POS. Importantly, the produced short-chain POS fraction demonstrated enhanced prebiotic activity, particularly for bacterial strains of the family Lactobacillaceae, compared to a yeast strain. These findings provide a sustainable, biorefinery-compatible approach for extracting and modifying RSM polysaccharides, supporting the development of structurally defined POS as novel prebiotics. Full article

Global demand for sustainable food packaging materials has intensified research on bio-based biopolymer systems capable of delivering functional compounds. Among these, protein–polysaccharide gels have emerged as versatile matrices for the incorporation and controlled release of antioxidant and antimicrobial agents. This review examines recent advances in the design and functionality of protein–polysaccharide gel systems for active food packaging applications. Particular attention is given to representative hybrid matrices such as casein/chitosan, gelatin/alginate, and whey protein/pectin systems, highlighting their gelation mechanisms, molecular interactions, and physicochemical properties. Furthermore, the review explores the potential of agro-industrial and marine by-products as renewable sources of proteins, polysaccharides, and bioactive compounds within circular bioeconomy strategies. Current limitations related to stability, scalability, and regulatory compliance are also addressed. By integrating structural, functional, and sustainability perspectives, this work provides a comprehensive framework for the development of next-generation protein–polysaccharide gel carriers for active food packaging. Full article

Pectins are structurally complex plant polysaccharides whose functional properties strongly depend on molecular structure that may vary depending on the source of origin. The present study aimed to characterize and compare the hydrodynamic properties of pectins obtained from red and blackcurrants in semidilute and concentrated aqueous solutions. Pectins were extracted and analyzed using light scattering methods and rheology at 25 °C, 30 °C, 35 °C and 40 °C. The methodology used enabled the determination of the hydrodynamic properties of the pectins with changing temperature and concentration, and mathematical modeling was performed using the Kohlrausch–Williams–Watts model. The obtained samples differed in molecular structure, and these differences were reflected in the chain behavior in aqueous solution. The results indicate that even closely related botanical sources may yield pectins with significantly different functional properties. Hydrodynamic studies revealed that relaxation phenomena occurred in a similar manner for redcurrant pectin in the concentrated region and for blackcurrant pectin in the semidilute region (similar diffusion coefficients). Under shear flow conditions, blackcurrant pectin solutions behaved like Newtonian fluids, whereas redcurrant pectin exhibited complex, non-Newtonian behavior. Redcurrant pectin solutions also exhibited lower apparent viscosity values at concentrations comparable to those of blackcurrant pectin. The ability to scale apparent viscosity values indicated a unchanging friction mechanism in viscous flow, characteristic of semidilute and concentrated regions. Full article

The fining of red wines is a crucial process for enhancing their sensory quality, involving the elimination of compounds that compromise stability or generate undesirable attributes. Against the backdrop of growing interest in sustainable and allergen-free alternatives, this study examines the potential of using cell wall material from white grape pomace (Zalema, Pedro Ximénez and Moscatel varieties) as fining agents in red wine. Cell wall samples were isolated and characterised using attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR). PCA applied to the cell wall spectra revealed homogeneous matrices dominated by structural polysaccharides, including cellulose, hemicellulose, lignin, pectins and arabinogalactans. Following the fining treatments, significant differences were observed in the generated sediments compared to the control, primarily due to signals attributable to phenols, proteins, and carbohydrates. This demonstrates the active involvement of these compounds in the formation of precipitates. The results confirm that the composition of the cell wall favours interaction with phenols and proteins in wine, thereby contributing to their elimination. Overall, this work demonstrates the potential of cell wall material from white grape pomace as plant-based oenological fining agents, providing new insights into the molecular mechanisms of action. Full article

The spherical pectin is an important bioactive component of chrysanthemum tea infusion, but its biological function, primary structure, and structure-activity relationship remain unclear. The present study evaluated the immunostimulatory activity of spherical pectin from Chrysanthemummorifolium Ramat. ‘Hangbaiju’ tea infusion in RAW264.7 cells and preliminarily investigated its structure-immunostimulatory activity relationship. The rhamnogalacturonan-I (RG-I) domain played a key role in the immunostimulatory activity of spherical pectin. Terminal and branched arabinose residues together accounted for 73.8% of the total arabinose residues in spherical pectin, indicating that the arabinan chains of spherical pectin were highly branched. The backbone of these arabinan chains consisted of →5)-α-Araf-(1→ repeats, and additional →5)-α-Araf-(1→ branches were linked to the backbone via α-1,3-glycosidic linkages. The spherical pectin rich in highly branched arabinan chains activated RAW264.7 cells via recognition by toll-like receptor 4 (TLR4). Molecular docking analysis revealed that →5)-α-Araf-(1→ branches in spherical pectin could bind to toll-like receptor 4/myeloid differentiation protein-2 (TLR4/MD-2) complexes and stabilize the dimer structure, which represents an important mechanism for its immunostimulatory activity. This study provides new insights into the structure-function relationship of spherical pectin. Full article

Background: Traditionally, wild jujube (Ziziphus jujuba Mill. var. spinosa (Bunge) Hu ex H. F. Chou) has been used to nourish the heart, calm the spirit, and arrest spontaneous sweating. Modern research confirms its broad pharmacological activities, including antioxidant, anti-inflammatory, neuroprotective, and cognitive-enhancing effects. This study aims to isolate and characterize the structure of jujube polysaccharides and evaluate their protective effects against oxidative stress damage in neural stem cells (NSCs). Methods: We successfully isolated and purified a novel pectin polysaccharide (ZJP-2) from wild jujube. Its structure was characterized in detail using high-performance liquid chromatography coupled with multi-angle laser light scattering and refractive index detection (HPLC-MALS-RI), high-performance anion exchange chromatography (HPAEC), gas chromatography–mass spectrometry (GC-MS), and nuclear magnetic resonance (NMR) spectroscopy. Results: Structural analysis revealed that ZJP-2 is a pectin heteropolysaccharide with a molecular weight of approximately 67.93 kDa. Its monosaccharide composition primarily includes galac-turonic acid (GalA), arabinose (Ara), rhamnose (Rha), galactose (Gal), and glucose (Glc). The backbone consists of α-GalA and rhamnose-galacturonic acid-I (RG-I) domains linked by (1→4)-glycosidic bonds. NMR spectroscopy further confirmed its glycosidic bond types. In activity assessment, our study demonstrated that ZJP-2 significantly alleviated DMNQ-induced oxidative stress damage in C17.2 neural stem cells. Its protective effect was achieved by reducing intracellular reactive oxygen species (ROS) levels and upregulating the mRNA expression of antioxidant genes associated with the signaling axis (p < 0.05). Moreover, ZJP-2 suppressed DMNQ-induced overexpression of Nestin and NeuN (p < 0.05), contributing to the maintenance of NSCs’ undifferentiated state and functional homeostasis. Conclusions: In conclusion, ZJP-2 possesses distinct structural characteristics and significant neuroprotective potential, supporting its development as a natural functional food or dietary supplement for preventing oxidative stress-related neural damage. Full article

As a traditional dual-purpose ingredient for both medicine and food, the biomacromolecules in Panax ginseng include polysaccharides, pectin, exosomes, proteins and dietary fiber. Due to their unique chemical structures, physiological activities, and processing adaptability, these components have achieved diversified applications in the medical field, becoming one of the core raw materials for functional food development. Modern research shows that the biomacromolecules found in ginseng can regulate the body’s immunity, antioxidant and anti-tumor properties, as well as antibacterial properties and the ability to enhance the body’s metabolic capacity, demonstrating significant application potential in healthcare-related fields. Recent studies have found that in addition to the root, the stems, leaves, fruits and flowers of P. ginseng also contain various effective components such as ginseng polysaccharides and pectin, which have enhanced the utilization value of ginseng plant resources. Ginseng biomacromolecules can not only replace antibiotics but also improve the production performance of animals by influencing the structure of intestinal flora, providing raw materials for the selection and application of natural feed additives for animals. This review summarizes the latest research findings on the pharmacological properties and practical applications of ginseng-derived biomolecules. It primarily addresses the structural characteristics, pharmacological activities, and current applications in health and medicine of biomolecules such as ginseng polysaccharides, ginseng exosomes, ginseng proteins, and ginseng dietary fiber. It aims to provide a fresh perspective and a solid theoretical foundation for the in-depth development of ginseng in the fields of medicine and molecular biology. Full article

This study aimed to investigate the changes in textural properties of two potato varieties (JZ-226 and XS-6) during boiling and to elucidate the interaction mechanisms within their starch–pectin composite systems, and their impacts on textural characteristics. The results showed that during the boiling process, both potato varieties exhibited decreased hardness and chewiness. As the boiling time lengthened, starch underwent gelatinization; the amylose content dropped; water solubility increased; and the swelling power, transparency, and iodine blue value reduced. Meanwhile, pectin degraded, with the degree of esterification increasing; the content of protopectin and other bound pectins decreased; and water-soluble pectin increased, along with molecular weight rising. In the early stages of gelatinization (15 min), the addition of pectin inhibited the short-range orderliness of starch, forming a relatively stable network structure. However, prolonged gelation disrupts the gel network structure of the starch–pectin complex, leading to further textural changes. Compared to XS-6, the pectin in JZ-226 demonstrated a stronger ability to inhibit starch short-range orderliness, forming a more stable network structure, thereby maintaining superior hardness. These findings provide a theoretical basis for understanding the molecular mechanisms underlying textural changes in potato processing and offer technical support for developing functional potato products. Full article

In this study, a pectin polysaccharide named DESP was extracted using a deep eutectic solvent (DES) from sweet potato residue (SPR) and the extract was optimized through response surface methodology (RSM). The DESP, based on choline chloride–urea (ChCl-Ur), was characterized for yield, molecular weight (Mw), and monosaccharide composition. Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ¹H-nuclearmagnetic resonance (¹H-NMR), and scanning electron microscopy (SEM) were used to analyze the structure. Optimal extraction conditions for DESP were ChCl-Ur in a molar ratio of 1:2, water content of 75 wt.%, extraction time of 125.7 min, extraction temperature of 83.2 °C, and a liquid-to-solid ratio of 37.0 mL·g⁻¹. The optimized extraction yield was 5.6% ± 0.09%, which was 2.4 times higher than that of hot-water-extracted sweet potato pectin (HWSP, 2.32%). The monosaccharide analysis revealed that galacturonic acid (GalA) was the most abundant saccharide, followed by glucose (Glc), galactose (Gal), arabinose (Ara), and rhamnose (Rha). The Mw of DESP was 20.90 kDa, which was lower than that of HWSP and HASP. In addition, DESP exhibited certain anti-inflammatory activity. Full article

This study aimed to elucidate the structure–activity relationship between the structural characteristics of three plant-derived polysaccharides, Lycium barbarum polysaccharide (LBP), citrus pectin (CP) and peach gum polysaccharide (PGP), and their prebiotic functionalities. Structural analysis indicated that LBP exhibited a medium molecular weight and was rich in galactose and rhamnose, which contributed to its high uronic acid content, strong antioxidant activity, and sustained fermentation profile with enhanced butyrate production. In contrast, CP, with its low molecular weight and neutral linear glucan backbone, was rapidly utilized by gut microbiota, leading to accelerated propionate accumulation. Meanwhile, PGP, characterized by an ultra-high molecular weight and a highly branched arabinogalactan configuration, acted as a specific substrate that promoted mid- to late-stage fermentation and significantly increased butyrate yield, highlighting its prebiotic property driven by structural complexity. The functional differences among these polysaccharides were determined by their monosaccharide composition, molecular weight distribution, and chain conformation. These findings provide a scientific basis for the targeted development of plant-derived prebiotics aimed at specific metabolic functions. Full article