Search Results (161)

The complex plant cell wall heteropolysaccharide xylan, and its breakdown products xylo-oligosaccharides and xylose, are value-added compounds with a plethora of potential applications in diverse areas. They are nonetheless currently poorly exploited, with a major bottleneck being the unavailability of efficient, low-cost, high-yield production processes. The major objective of the present study is to identify and characterise a high-yield process for the preparation of highly pure xylan/XOS products from the macroalga Palmaria palmata. Currently, most xylan is extracted from land-sourced lignocellulosic feedstocks, but we take advantage of the high xylan content, xylan aqueous solubility, lignin-free nature, weakly linked cell wall matrix, and sustainability of the macroalga to identify a simple, sustainable, high-yield, novel-xylan-structure extraction process. This is composed of five steps: alga oven drying, milling, aqueous extraction, centrifugation, and dialysis, and we show that the alga preservation step plays a critical role in component extractability, with oven drying at high temperatures, ~100 °C, enhancing the subsequent aqueous extraction process, and providing for xylan yields as high as 80% of a highly pure (~90%) xylan product. The process developed herein and the insights gained will promote a greater availability of these bioactive compounds and open up their application potential. Full article

Hyaluronic acid (HA) is a linear heteropolysaccharide that naturally occurs in vertebrates. Thanks to its unique physico-chemical properties, it is involved in many key processes in living organisms. These biological activities provide the basis for its broad applications in cosmetics, medicine, and the food industry. The molecular weight of HA might vary significantly, as it can be less than 10 kDa or reach more than 6000 kDa. There is a strong correlation between variations in its molecular weight and bioactivities, as well as with various pathological processes. Consequently, monodispersity is a crucial requirement for HA production, together with purity and safety. Common industrial approaches, such as extraction from animal sources and microbial fermentation, have limits in fulfilling these requests. Research and protein engineering with hyaluronic acid synthases can provide a strong tool for the production of monodisperse HA. One-pot multi-enzyme reactions that include in situ nucleotide phosphate regeneration systems might represent the future of HA production. In this review, we explore the current knowledge about HA, its production, hyaluronic synthases, the most recent stage of in vitro enzymatic synthesis research, and one-pot approaches. Full article

This study aimed to optimize the enzyme-assisted extraction of polysaccharides (RTFPs) from Rosa roxburghii fruit using response surface methodology. Under the optimal extraction conditions, the yield of RTFPs reached 14.02%, which was close to the predicted value of 13.96%. The primary structural characteristics and the antioxidative and immunomodulatory activities of RTFPs were also examined. Structural characterization revealed that RTFPs comprise 36.38% neutral sugar, 48.83% uronic acid, and 7.29% protein. Their heteropolysaccharide structure features two distinct molecular weight fractions (1.87 × 10⁵ Da and 4.75 × 10³ Da) and a monosaccharide composition dominated by glucose (38.93%), arabinose (20.66%), galactose (20.58%), galacturonic acid (10.94%), and xylose (6.52%). Antioxidant assays demonstrated potent radical scavenging activity, with IC₅₀ values of 11 μg/mL (DPPH) and 150 μg/mL (ABTS), comparable to conventional antioxidants. Immunomodulatory studies on RAW264.7 macrophages revealed that RTFPs (100–400 μg/mL) significantly enhanced phagocytosis by 12.61–76.63% and stimulated the secretion of nitric oxide (NO) and tumor necrosis factor-α (TNF-α). These bioactivities are attributed to RTFPs’ high uronic acid content, moderate molecular weight distribution, unique monosaccharide profile, and highly branched conformation. Full article

Diabetes mellitus (DM), a chronic metabolic disease, poses a significant challenge to global health. Although type 1 diabetes mellitus (T1DM), type 2 diabetes mellitus (T2DM), gestational diabetes mellitus (GDM), and other types of diabetes mellitus differ in pathological mechanisms, they converge in that hyperglycemia is a universal clinical hallmark. Currently, the antidiabetic medications employed in clinical practice for blood glucose management require long-term administration and are associated with various side effects that can adversely impact human health. Plant heteropolysaccharides have emerged as promising candidates for anti-diabetic therapy, owing to their abundant natural sources, absence of toxicities, and confirmed hypoglycemic activities. This review aims to summarize the anti-diabetic mechanisms of plant heteropolysaccharides by dissecting the key biological pathways associated with clinical intervention in DM, including the modulation of insulin secretion, a reduction in insulin resistance, and an alteration in the composition of the gut microbiota. For these reasons, these findings provide a theoretical framework for the clinical application of plant heteropolysaccharides and indicate that they are expected to become natural agents used in treating DM. Full article

This study aimed to identify the heat-resistant bioactive components of Enterococcus faecium HDRsEf1 (HDRsEf1) and investigate their beneficial mechanism. Heat-treated culture supernatants of HDRsEf1 significantly suppressed CXCL-1 expression in LPS-stimulated MODE-K cells (p < 0.001), indicating the presence of heat-resistant anti-inflammatory components. Crude protein (P-Ef1) and crude expolysaccharide (EPS-Ef1) were isolated from an HDRsEf1 culture supernatant using ammonium sulfate and ethanal precipitation. Critically, only crude EPS-Ef1 retained an anti-inflammatory effect after heat treatment, while crude P-Ef1 lost this activity. Further investigation revealed that crude EPS-Ef1 (25 μg/mL) promoted MODE-K cell proliferation via EdU assays (p < 0.001), potentially through an upregulation of PCNA mRNA expression (p < 0.001). Animal studies demonstrated that an oral administration of crude EPS-Ef1 (4 mg/kg bw, 14 days) significantly increased body weight gain and jejunal crypt depth (p < 0.05) while reducing intestinal CXCL-1 mRNA levels (p < 0.001). These in vivo findings are consistent with in vitro observations. A structural analysis using HPAEC and SEC-MALLS-RI characterized crude EPS-Ef1 as a heteropolysaccharide (Mw 80.3 kDa) with a near-spherical conformation (slope 0.13) composed of mannose, glucose, glucuronic acid, and galactose (5.4:4.4:1.2:1). In summary, this study identifies crude EPS-Ef1 as the heat-resistant postbiotic component. Crude EPS-Ef1 possesses the dual effects of suppressing intestinal inflammation and promoting intestinal epithelial cell proliferation, which provides a theoretical foundation for a crude EPS-Ef1-based postbiotic. Full article

The ulvans are sulfated heteropolysaccharides that can stimulate the immune response in vitro. Using a human cell model, this study aimed to characterize and evaluate the immunostimulatory properties of crude ulvans extracted from Ulva spp., collected in Algarrobo, Chile. The crude ulvans, characterized by spectrophotometric methods, are composed of 47.6% total sugars, 14.3% uronic acids, and 8.9% sulfates, with an average molecular weight of 40.000 kDa. The FTIR spectrum showed bands related to uronic acids, rhamnose, and sulfate groups. GCMS analysis confirmed the presence of rhamnose, xylose, glucose, and galactose, with a predominance of the disaccharides U3s and B3s. HL60 cells differentiated into macrophages were cultured with three concentrations of crude ulvans (25, 50, and 100 μg/mL), with cell viability remaining above 90% at the lower concentrations. The crude ulvan activated CD86 co-stimulatory molecules and promoted the release of IL-6, IL-10, IL-4, and nitric oxide cytokines. The results suggest that ulvan is non-toxic and can activate inflammatory pathways, making it a potential candidate for studies as a vaccine adjuvant. Full article

Brasenia schreberi (BS) is a perennial aquatic plant of the water lily family, of which the recognition as a functional food is on the rise. Polysaccharides from BS have been found to possess antihyperglycemic and antihyperlipidemic activities. This study aimed to partially clarify the structural and evaluate the hypoglycemic potentials of Brasenia schreberi polysaccharide (BSP). In this study, BSP was isolated from the mucilage covering the surface of Brasenia schreberi (BS). SEM and AFM results verified that BSP molecules were tightly connected and formed a ring-shaped network structure. Further structural analysis showed that BSP was an acidic heteropolysaccharide with a molecular weight of 2.47 × 10⁴ Da. It had 1,2,3-linked α-D-Galp, 1,2-linked α-D-Manp, and 1,4-linked β-GlcA residues as the main chain, with 1,3-linked α-Galp, 1,3-linked α-Fucp, 1,3-linked α-Xylp, T-Araf, and T-Rhap as side chains. The rheological results indicated that the BSP solution was a pseudoplastic fluid and exhibited shear-thinning properties. Moreover, the gel strength and texture properties of BSP tended to be higher as the BSP and Ca²⁺ concentration increased. More importantly, BSP exhibited good inhibitory activity against α-amylase and α-glucosidase, indicating that it may be a good candidate for a hypoglycemic functional food. Full article

In this study, we extracted, separated, and purified polysaccharides from Se-enriched Cyclocarya paliurus (Se-CPP-1) and compared them with their non-Se-enriched counterparts (CPP-1) to investigate the impact of selenium on their structural and functional properties. Structural characterization by HPLC, GC-MS, and SEM revealed that Se-CPP-1 is an acidic heteropolysaccharide with a lower molecular weight (76.6 vs. 109.22 kDa), smaller particle size (418.22 vs. 536.96 nm), and higher negative zeta potential (−43.15 vs. −21.29 mV), indicating enhanced colloidal stability. SEM imaging further demonstrated a distinctive flaky morphology in Se-CPP-1. Functional assays showed that Se-CPP-1 significantly outperformed CPP-1 in scavenging free radicals (DPPH/ABTS), stimulating RAW264.7 macrophage proliferation (CCK-8 assay), enhancing phagocytic activity, and promoting NO secretion. These improvements were attributed to selenium-induced modifications in polysaccharide conformation and surface properties. Our findings highlight the potential of selenium fortification in developing high-efficacy C. paliurus polysaccharides for antioxidant and immunomodulatory applications. Full article

Dictyophora indusiata is commonly utilized as a functional food in China and other Asian countries. The peach-shaped phase of this fungus is nutritionally and taste-wise similar to its mature fruiting bodies. However, there is limited research on the polysaccharides found in the peach-shaped D. indusiata. A heteropolysaccharide was extracted from the volva of peach-shaped D. indusiata (DIVP). Analyses using high-performance gel permeation chromatography, methylation and NMR revealed that DIVP comprises glucose, glucuronic acid, galactose, and mannose. Its structure features a backbone that consists of →3)-β-D-Glcp-(1→ units with branches at →4)-β-D-Glcp-(1→, →6)-α-D-Galp-(1→ and terminal α-Manp-(1→ residues. Physicochemical assessments including X-ray diffraction, thermal, zeta potential and viscosity characterization indicated that DIVP is a semi-crystalline polymer exhibiting excellent physical and thermal stability. Cytokine antibody array and proteome profiler human phosphokinase analyses demonstrated that DIVP downregulates the expression levels of cytokines and alters the phosphorylation status of 16 proteins in human U937 macrophages induced by lipopolysaccharides, indicating its anti-inflammatory activity. These findings suggest that the polysaccharide from the volva of peach-shaped D. indusiata is primarily composed of β-1,3-glucan, which exhibits stable physicochemical properties and anti-inflammatory activity, providing a foundation for its potential use as an anti-inflammatory agent or functional food. Full article

Lacticaseibacillus (L.) rhamnosus CRL75 is a lactic acid bacterium (LAB) isolated from local dairy products, demonstrating significant adaptation in skimmed milk (FM75). In this context, CRL75 exhibited high microbial growth (3.63 ± 0.18 log CFU·mL⁻¹), strong acidification (9.20 ± 0.10 g·L⁻¹ lactic acid, and 2.40 ± 0.10 pH units), and increased viscosity in FM75 after 16 h of fermentation. Additionally, this LAB strain produces both capsular polysaccharides (CPS+) and extracellular polysaccharides (EPS75), contributing to a ropy phenotype (>10 cm). The purified EPS75 (70.70 ± 3.25 mg·L⁻¹) displayed low molecular weight (12.7 kDa), with galactose and glucose as its primary monomers in a 4:1 ratio. In aqueous environments, EPS75 exhibited an extended size (147 nm), a random coil structure, and macromolecular aggregation. Furthermore, vibrational spectroscopy confirmed the presence of a neutral EPS with high thermal stability. Additionally, EPS75 exhibited dose-dependent antioxidant activity, effectively reducing metal ions (Fe³⁺, Mo⁶⁺, and Mn⁷⁺) and stabilizing radicals (ABTS^•+, HO^•, O₂^•−, and HOO^•). The biopolymer also demonstrated immunostimulatory and anti-inflammatory effects in RAW 264.7 cells. In vivo assays using Balb/c mice indicated that both EPS75 and FM75 prevented constipation, suggesting their potential as natural and safe agents for constipation-related disorders. Due to its viscosifying and health-promoting attributes, CRL75 offers promising applications for functional dairy products. Full article

Selenium–polysaccharides possess antioxidant properties, making them promising materials for functional foods, pharmaceuticals, and clinical applications. This study examines the incorporation of selenium into polysaccharides via mycelial biosynthesis and its effects on structure and antioxidant activity. Polysaccharides obtained from Lentinula edodes-submerged cultures grown in Se-supplemented and non-supplemented media were analysed for Se content (RP-HPLC/FLD), structure (FT-IR, HPLC, and HPGPC-ELSD), and antioxidant activity (DPPH scavenging, reducing power, and Fe²⁺ chelation). Two low-molecular-weight Se–heteropolysaccharides (Se-FE-1.1 and Se-FE-1.2) containing ~80 and 125 µg/g Se were isolated, primarily composed of glucose, mannose, and galactose with β-glycosidic linkages. Se incorporation into polysaccharides selectively enhanced their antioxidant activity in the DPPH radical scavenging assay, with minimal effects observed in iron chelation and reducing power assays. Crude Se–polysaccharides displayed the highest antioxidant activity, suggesting an additional contribution from protein components. Our findings demonstrate that Se is effectively incorporated into polysaccharides, altering monosaccharide composition while preserving glycosidic linkages. The selective enhancement of radical scavenging suggests that selenium plays a specific role in antioxidant activity, primarily influencing radical scavenging mechanisms rather than interactions with metal ions. Further research is needed to clarify the mechanisms of selenium incorporation, the nature of its bonding within the polysaccharide molecule, and its impact on biological activity. Full article

Lactic acid bacteria (LAB) exopolysaccharides (EPSs) have garnered significant scientific interest due to their multifaceted roles in food technology and health promotion. This comprehensive review systematically examines the structural classification of LAB EPSs, emphasizing distinctions between homo-and heteropolysaccharides, as well as the influence of substituent groups (e. g., acetyl, phosphate) on their physicochemical and bioactive properties. Advanced isolation methodologies, including ethanol precipitation and ultrafiltration, coupled with characterization techniques such as nuclear magnetic resonance (NMR) spectroscopy and atomic force microscopy (AFM), are vital for deciphering their chemical and physical characteristics. The biosynthesis pathway, governed by eps operons and modulated by environmental factors (e.g., carbon sources, Ca²⁺), are discussed as targets for genetic engineering to enhance yield and functionality. Functionally, LAB EPSs display antioxidant, immunomodulatory, anti-tumor, anti-viral, and anti-biofilm activities, with demonstrated applications as natural additives in the food industry, prebiotics, and drug delivery systems. Despite their potential, challenges such as cost-effective production and regulatory hurdles persist. Future research should prioritize the elucidation of molecular mechanisms, clinical validation of health claims, and sustainable bioprocessing innovations to fully harness the transformative potential of LAB EPSs across food, pharmaceutical, and agricultural industries. Full article

Coriander (Coriandrum sativum) is a classical medicinal and edible herb as well as a spice, but the physicochemical and biological properties of its polysaccharides have not been fully studied. In this study, the polysaccharides were extracted using an ultrasonic-assisted method and purified from fresh coriander, and then the coriander polysaccharide (CSP) fraction was separated using an agarose gel Q-Sepharose Fast Flow column. The total sugar content, protein content and monosaccharides composition of CSPs were determined using a phenol–sulfuric acid method, Coomassie Brilliant Blue method and HPLC. The structural characterization was detected using ultraviolet spectrophotometry and FT-IR spectroscopy. DPPH and ABTS free radicals were used to explore their antioxidant activities, while the inhibitory abilities of α-amylase and α-glucosidase were used to evaluate their hypoglycemic activity. After that, the immunomodulatory and antitumor activities were investigated using macrophage RAW264.7 and HepG2 cells as the targets. The results showed that the total sugar and protein contents of CSPs were 66.90 ± 1.44% and 1.06 ± 0.32%, respectively. CSPs were mainly composed of fucose, rhamnose, arabinose, galactose, glucose, galacturonic acid and glucuronic acid, with a molar ratio of 1.13:15.11:9.60:25.98:1.55:44.33:2.29, and may be an acidic heteropolysaccharide containing pyran rings, α- and β-glycosidic bonds and glucuronic acid. Results from in vitro experiments of biological activities showed that the IC₅₀ of CSPs for scavenging DPPH and ABTS free radicals were 0.759 mg/mL and 1.758 mg/mL, respectively; the IC₅₀ values for inhibiting the activities of α-amylase and α-glucosidase were 0.634 mg/mL and 2.178 mg/mL, respectively; the CSPs with a concentration of 25~200 μg/mL showed no obvious toxicity to macrophage RAW264.7, and when treated with 100 μg/mL of CSPs, the relative cell phagocytosis capacity and secreted nitric oxide amount of RAW264.7 were 153.75 ± 12.01% and 133.56 ± 5.37%, respectively; CSPs showed a concentration-dependent ability to inhibit the growth of HepG2 cells within the test concentration of 0.25–2.0 mg/mL. Summarizing the results, due to their excellent antioxidant, immunomodulatory and anti-tumor activities, the coriander acid polysaccharides were expected to show good potential in comprehensive development of food and medicine. Full article

The formulation of polysaccharide-based beads encapsulating Trichoderma spp. represents an eco-friendly strategy for promoting sustainable and efficient agriculture. Trichoderma, a beneficial fungus, is well known for its ability to enhance plant growth, combat phytopathogens, and improve soil health. Encapsulating Trichoderma spores in a polysaccharide matrix provides a protective environment that ensures their viability and facilitates their controlled release into the soil. Alginate is a natural polymer found in various species of brown algae and certain bacteria. Pectin is a heteropolysaccharide present naturally in the cell walls of all higher plants. Due to their distinctive characteristics, alginate and pectin are regarded as promising carrier materials for the encapsulation of bioactive agents. In this work, alginate (Alg) beads, pectin (Pec) beads extracted from orange peel, and Alg/Pec composite beads in a 50/50 (w/w) ratio encapsulating Trichoderma S1 (1.83 × 10⁴ conidia/mL) and S2 (1.56 × 10⁸ conidia/mL) were prepared using the ionic gelation method. The moisture content of the prepared beads was evaluated. The size and shape of the beads were determined by analyzing images obtained by an XE3910 optical microscope. The average size of the microcapsules (wet)varied from 1886 ± 6.557 μm to 1942 ± 28.688 μm. All samples were characterized by Fourier transform infrared spectroscopy (FTIR). The overall results demonstrated the successful encapsulation of Trichoderma spp. and highlighted the effects of the different formulations on the physicochemical properties of the beads. Full article

Geum japonicum Thunb. var. Chinese F. Bolle, a traditional Miao medicine with significant clinical potential, is rich in polysaccharides. Despite its importance, there is a scarcity of research on the structure and activities of these polysaccharides. In this study, polysaccharides from Geum japonicum (GJPs) were extracted using various methods, including heated reflux extraction (HRE), acidic extraction (ACE), alkaline extraction (AAE), microwave-assisted extraction (MAE), enzymatic extraction (EAE), pressurized liquid extraction (PLE), and deep eutectic solvents extraction (DESE). The extraction yield, physicochemical properties, structural characteristics, and antioxidant activities of these polysaccharides were comprehensively investigated and compared. Physicochemical analysis, including FT-IR spectral features and monosaccharide compositions, revealed that the GJPs are acidic heteropolysaccharides with both α- and β-configurations. DESE and ACE were the most effective methods for obtaining the highest neutral and acidic sugars with yields of 29.1%/64.2%, and 39.8%/55.6%, respectively. Meanwhile, AAE was preferable for extracting the polysaccharide–protein complex, achieving a yield of 14.21% and exhibiting superior thermal stability. In particular, DESE and PLE showed the best homogeneity with distinct molecular weights of 39.5 kDa and 17.6 kDa, respectively. In addition, biological evaluation indicated that DESE and MAE exhibited relatively stronger antioxidant activities as evidenced by DPPH and ABTS assays. Conversely, ACE demonstrated highest Fe²⁺ chelating ability but the lowest activity in DPPH and ABTS assays. Furthermore, the results of correlation analysis showed that the monosaccharides composition, protein and polyphenol content were significantly associated with the antioxidant activity. The choice of extraction method greatly affects the property and activity of G. japonicum polysaccharides. Polysaccharides extracted by deep eutectic solvents from G. japonicum show promise as natural antioxidants in the food and medicine industries. Full article