Polysaccharides from Flos Sophorae Immaturus ameliorates insulin resistance in IR-HepG2 cells by co-regulating signaling pathways of AMPK and IRS-1/PI3K/AKT.

Four polysaccharides, named FSIP, FSIP-I, FSIP-II and FSIP-III, were isolated from Flos Sophorae Immaturus. Structure characterization revealed that FSIP-I and FSIP-II were types of AG-II-like polysaccharides while FSIP-III featured a RG-II-like structure with high content of GalpA. In vitro experiments showed that FSIPs upregulated HK and PK activities in glycolysis while downregulated G-6-Pase activities in gluconeogenesis. This increased glucose utilization while decreased the glucose synthesis in IR-HepG2 cells, potentially reducing elevated blood sugar levels induced by excess insulin. In terms of antioxidant system, FSIPs decreased the levels of ROS and MDA, and increased the activities of SOD and CAT, enhancing antioxidant capacity to counteract damage caused by insulin resistance in IR-HepG2 cells. To further explore the mechanism, related genes expressions were analyzed. The results found that FSIPs ameliorated insulin resistance via regulating AMPK and IRS-1/PI3K/AKT signal pathways. In the case of AMPK, glucose can be channeled into oxidative (catabolic) pathway, whereas, in the case of IRS-1/PI3K/AKT, glucose can be stored as glycogen (anabolic). This co-modulation could ameliorate insulin resistance by upregulating the glycolysis and repressing the gluconeogenesis in catabolism, and upregulating the glycogen synthesis in anabolism. Additionally, FSIP-III exhibited better anti-insulin resistance activity, attributed to its high content of GalpA.

Purification, structural characterization and immunomodulatory activity of a polysaccharide isolated from Scutellaria baicalensis stem-leaf.

In our research, a novel polysaccharide (named SSP-3a) with uniform molecular weight was extracted from Scutellaria baicalensis stem-leaf. The structural analysis revealed that SSP-3a was an acidic polysaccharide with a heavy average molecular weight of 1.83 × 105 Da. By HPLC, the primary constituents of SSP-3a were mannose (11.60 %), glucuronic acid (42.99 %), glucose (23.43 %), and xylose (22.04 %). According to FT-IR and 1H NMR analysis, it was confirmed to be a ß-configuration pyranose with a CO stretching vibrational peak. The immunomodulation results also showed that SSP-3a not only significantly promoted RAW264.7 cell proliferation and phagocytosis, but also stimulated the release of NO and cytokines. Furthermore, mechanistic studies suggested that SSP-3a had the ability to trigger MAPKs and NF-κB immunological signaling pathways via TLR4 receptors. The findings suggested that SSP-3a might be a beneficial active component for the food and pharmaceutical industries.

Structure characterization and immunoactivity on dendritic cells of two neutral polysaccharides from Dictyophora rubrovalvata.

Dictyophora rubrovalvata is a valuable fungus homologous to food and medicine, and its polysaccharide have been gaining increasing attention because of its plentiful activity. However, the structure and activity of its homogeneous polysaccharide have not been studied enough. In this study, two polysaccharides DRP-I and DRP-II were purified from D. rubrovalvata. Their structures were characterized by chemical composition, monosaccharide composition analysis, methylation analysis and nuclear magnetic resonance spectroscopy. The results showed that DRP-I and DRP-II were neutral heteropolysaccharides with molecular weights of 5.79 × 103 and 1.25 × 104 Da, respectively, which were composed of mannose, galactose, glucose, xylose and fucose. The main chains were → 6)-α-D-Galp-(1 → 6)-α-D-Galp-(2,1 → 6)-α-D-Manp-(2,1 → 6)-α-D-Galp-(1, and branch chains were ß-D-Xylp-(1 → 3)-α-L-Fucp-(1 → 4)-α-D-Manp-(1 → and α-D-Galp-(1 → 3)-α-D-Galp-(1 → . The in vitro immunoactivity assays on dendritic cells showed that DRP-I and DRP-II could up-regulate the expression of IL-10 and IL-6 and inhibit the expression of TNF-α in a concentration-dependent manner. This research indicated that DRP-I and DRP-II possessed immunoactivity by balancing the excessive inflammation, and molecular weight is an important factor affecting immunoactivity.

Structural characterization and immunoregulatory mechanism of a low-molecular-weight polysaccharide from lotus root.

The extraction of polysaccharide from lotus root was highly homogenized, and the structure of the polysaccharide was not clear. Herein, we report a hot water method combined with α-amylase that was applied to extract lotus root polysaccharide. After purified, a lotus root polysaccharide fraction LP60-a with high purity and low molecule weight was obtained. Systematic characterization of the structure of LP60-a was achieved by monosaccharide composition, methylation and NMR analysis, showing that LP60-a was composed of α-1,6-glucan linked with a small amount of arabinogalactan. Conformational determination showed that LP60-a was a three-helix polysaccharide with random coil conformation. Furtherly, the immunomodulatory activities of LP60-a were investigated in RAW264.7 macrophages. The data indicated that LP60-a could enhance the proliferation and phagocytosis of macrophages significantly, and induce the expression of NO and TNF-α in macrophages without causing inflammation. Moreover, LP60-a promoted the phosphorylation of MAPK p38 and JNK, as well as NF-κB p65, indicating that LP60-a could activate RAW264.7 cells through MAPK and NF-κB signaling pathways. In conclusion, the results imply that LP60-a could enhance the immune function of macrophages, presenting a possibility to play a role as an immunomodulatory agent in dietary supplements.

Mapping conformational changes on bispecific antigen-binding biotherapeutic by covalent labeling and mass spectrometry.

Biotherapeutic's higher order structure (HOS) is a critical determinant of its functional properties and conformational relevance. Here, we evaluated two covalent labeling methods: diethylpyrocarbonate (DEPC)-labeling and fast photooxidation of proteins (FPOP), in conjunction with mass spectrometry (MS), to investigate structural modifications for the new class of immuno-oncological therapy known as bispecific antigen-binding biotherapeutics (BABB). The evaluated techniques unveiled subtle structural changes occurring at the amino acid residue level within the antigen-binding domain under both native and thermal stress conditions, which cannot be detected by conventional biophysical techniques, e.g., near-ultraviolet circular dichroism (NUV-CD). The determined variations in labeling uptake under native and stress conditions, corroborated by binding assays, shed light on the binding effect, and highlighted the potential of covalent-labeling methods to effectively monitor conformational changes that ultimately influence the product quality. Our study provides a foundation for implementing the developed techniques in elucidating the inherent structural characteristics of novel therapeutics and their conformational stability.

Valorizing Lycii fructus waste residue into polysaccharide-rich extracts: Extraction methodologies, physicochemical characterization, in vitro activities and economic feasibility.

The high polysaccharide content of Lycii fructus agri-food waste should be reclaimed for value liberation from both environmental and economic perspectives. In this study, waste from L. fructus pigment products was valorized on a bench scale by upcycling into active polysaccharide-rich extracts. The methodological feasibility of polysaccharide recovery from L. fructus waste was evaluated using sequential extraction techniques. Three fractions LFP-30, LFP-100, and LFP-121, were obtained under stepwise increases in temperature and pressure. Highly heterogeneous xyloglucan (XG)-pectin macromolecules composed of linear homogalacturonan (HG) and alternating intra-RG-I-linkers, with topological neutral branches and XG participation, were predominant among the L. fructus polysaccharides (LFPs). Antioxidant activities in LFPs were unaffected by waste resources and severe extraction methodology conditions. Additionally, the direct investment potential of polysaccharide recovery was evaluated for full-scale implementation. This study demonstrated the necessity and feasibility of extracting bioactive polysaccharides with potential applications from L. fructus waste, and provided a sustainable strategy for transforming L. fructus waste disposal problems into value-added products using cost-effective methodologies.

OSA modified porous starch acts as an efficient carrier for loading and sustainedly releasing naringin.

To select an efficient carrier for loading and sustainedly releasing naringin (NAR), complexes of porous starch (PS) and NAR (PS-NAR) as well as those of octenyl succinic anhydride (OSA) esterified PS and NAR (OSAPS-NAR) with different degree of substitution (DS) were prepared by an ultrasonic method with an ethanol solution. The micro-morphological features, structural and thermal properties of complexes and their constituents were characterized, and in vitro release rate and kinetic of NAR from complexes were investigated. The findings revealed that NAR was successfully loaded in PS/OSAPS in an amorphous form, and the NAR's loading efficiency improved as DS increased, reaching 86.85 % at DS 0.0427. NAR cumulative release rate from the complexes in simulated digestion fluids was much higher than that of free (unloaded) NAR, but decreased as DS increased. NAR's in vitro release from complexes mainly depended on the carrier rather than NAR itself, and OSAPS with higher DS had stronger protection and slower release effect on NAR. The results would provide a new means for starch-based carrier construction to develop an efficient delivery and sustainedly releasing system for NAR, thus broadening the application ranges both for modified starch and citrus flavonoids such as NAR.

Preparation and characterization of carboxymethylated Anemarrhena asphodeloides polysaccharide and its effect on the gelatinization of wheat starch.

In this study, a carboxymethylated Anemarrhena asphodeloides polysaccharide (CM-AARP) with an molecular weight (Mw) of 7.8 × 104 Da was obtained. CM-AARP was composed of four monosaccharides including d-mannose, d-glucose, d-galactose, and l-arabinose. Nuclear magnetic resonance (NMR) spectra revealed that the skeleton of CM-AARP was identical to that of AARP. Compared with AARP, CM-AARP had a superior inhibition effect on the gelatinization of wheat starch (WS) under the same condition. The addition of CM-AARP and AARP at 12 % enhanced the gelatinization temperature (60.47 ± 1.30 °C) of WS to 73.88 ± 0.49 °C and 69.75 ± 0.52 °C, respectively. CM-AARP could maintain the crystal structure of WS during gelatinization, the relative crystallinity with the 12 % CM-AARP addition was determined as 29.18 % ± 1.49 %, exceeding that of pure WS at 21.96 % ± 0.66 %. Moreover, CM-AARP influenced the rheological behavior of the gelatinized WS by reducing the viscosity and improving the fluidity. The results suggested that CM-AARP played an essential role in starch gelatinization and was a potential stabilizer in the starch-based food industry.

Higher Order Structure Differences Among Insulin Crystalline Drugs Revealed by 2D heteronuclear NMR.

During therapeutic protein development, two-dimensional (2D) heteronuclear NMR spectra can be a powerful analytical method for measuring protein higher order structure (HOS) in solution since the spectra exhibit much higher resolution than homonuclear 1H spectra. However, 2D NMR capabilities for characterizing protein HOS in crystalline states remain to be assessed, given the low 13C natural abundance and intrinsically broader lines in solid-state NMR (SSNMR). Herein, high-resolution heteronuclear correlation (HETCOR) SSNMR was utilized to directly measure intact crystal drug products of insulin human, insulin analogs of insulin lispro and insulin aspart. The fingerprint regions in 2D 1H-13C HETCOR spectra were identified, which distinguished the insulin crystals in their primary structure, HOS heterogeneity and dynamics, as well as the manufacturing processes. The HOS heterogeneity in insulin analogs is consistent with their therapeutic effect of rapid action; while insulin human crystals showed more structural homogeneity, consistent with their slower pharmacokinetics (PK) peak time than insulin analogs. Therefore, heteronuclear NMR could be broadly applicable to study protein drug dosage forms from liquid to solid, yielding improved molecular level structure data for assessing drug HOS in biosimilar drug development.

Identification of an arabinogalactan with special structure from Moringa Oleifera leaf and exploration of its immunomodulatory activity.

Arabinogalactan exhibits many biological activities, which is the candidate for functional food ingredients. However, there is limited research on the arabinogalactan from Moringa Oleifera leaf, and its structure needs to be more accurately characterized. This study investigated structural characteristics and immunomodulatory activity of a high-purity polysaccharide from Moringa oleifera leaf (i.e. MOLP-PE) to further explore arabinogalactan from Moringa Oleifera leaf and its potential application area. The results showed that MOLP-PE was a unique type II arabinogalactan: the main chain consisted of → 3, 4)-α-D-Galp-(1→, →3)-ß-D-Galp-(1→ and →2, 4)-ß-D-Rhap-(1→, with branches at the C-4 position of →3, 4)-α-D-Galp-(1→ and →2, 4)-ß-D-Rhap-(1→, consisting of →5)-α-L-Araf-(1→, →3)-α-L-Araf-(1→, →6)-ß-D-Galp-(1→ and →4)-ß-D-GalpA-(1→. Compared with arabinogalactan from larch, galactan and arabinan, MOLP-PE exhibited stronger ability in stimulating proliferation, phagocytosis and cytokines release of macrophages and bound with Toll-like receptor 4 closer via more binding sites, which might be due to its higher contents of 1,3-linked-Galp and 1,5-linked-Araf. These findings elucidated that MOLP-PE, as type II arabinogalactan with a unique structure, could be exploited as an immunomodulatory food ingredient.

Gel properties of Nicandra physalodes (Linn.) gaertn. seeds polysaccharides with tea polyphenols and its application.

The novel gelling polysaccharides (NPGP) were extracted and characterized from Nicandra physalodes (Linn.) Gaertn. seeds, while properties and potential application of NPGP gels with tea polyphenols were further explored. NPGP was composed of GalA, Glc, Rha, Gal, Xyl, Ara, and Man at a molar ratio of 71.87:17.13:3.10:2.55:2.19:1.64:1.52, with molecular weight of 6.32 × 104 Da and low methoxylation degree of 45.21%. The gelling properties of NPGP gel induced by tea polyphenols showed that tea polyphenols significantly improved the structural and rheological properties of NPGP gel, due to the formation of dense network by hydrogen bonds and the increase of crystalline degree of NPGP. NPGP gels with tea polyphenols could significantly ameliorated the texture, water-holding capacity, aggregation, leading force, and moisture distribution of surimi during freeze-thaw cycles. All results suggest that NPGP gels with tea polyphenols has fine properties and show potential to be applied as natural additives in food industry.

Structural characterization and hypoglycemic effect of polysaccharides of Polygonatum sibiricum.

Polygonatum sibiricum polysaccharide (PSP) was extracted and purified from raw material obtained from P. sibiricum. The structural features of PSP were investigated by Congo red, circular dichroism spectrum, high-performance gel permeation chromatography, scanning electron microscope, atomic force microscope, ultraviolet spectroscopy, and Fourier transform infrared spectroscopy analysis. In vitro simulations were conducted to investigate the kinetics of PSP enzyme inhibition. Moreover, a type II diabetes mouse model (T2DM) with streptozotocin-induced insulin resistance was established, and the indexes of lipid quadruple, insulin resistance index, oral glucose tolerance (OGTT), organ index, and pancreatic morphology of model mice were measured. The results showed that PSP mainly consists of monosaccharides, such as mannose, glucose, galactose, xylose, and arabinose. It also has a ß-glycosidic bond of a pyranose ring and an irregular reticulated aggregated structure with a triple helix. In vitro enzyme inhibition assays revealed that PSP acts as a reversible competitive inhibitor of α-glucosidase and α-amylase. Furthermore, PSP was found to reduce insulin resistance index, increase OGTT and serum insulin levels, decrease free fatty acid content to improve lipid metabolism, and lower glycated serum protein content to enhance glucose metabolism in T2DM mice, thereby leading to a reduction in blood glucose concentration. Additionally, PSP exhibited reparative effects on the damaged liver tissue cells and pancreatic tissue in T2DM mice. The experiment results provide a preliminary basis for the therapeutic mechanism of PSP about type II diabetes and a theoretical reference for application in food and pharmaceutical development.

Unambiguous Characterization of Commercial Natural (Dihydro)phenanthrene Compounds Is Vital in the Discovery of AMPK Activators.

These days, easy access to commercially available (poly)phenolic compounds has expanded the scope of potential research beyond the field of chemistry, particularly in the area of their bioactivity. However, the quality of these compounds is often overlooked or not even considered. This issue is illustrated in this study through the example of (dihydro)phenanthrenes, a group of natural products present in yams, as AMP-activated protein kinase (AMPK) activators. A study conducted in our group on a series of compounds, fully characterized using a combination of chemical synthesis, NMR and MS techniques, provided evidence that the conclusions of a previous study were erroneous, likely due to the use of a misidentified commercial compound by its supplier. Furthermore, we demonstrated that additional representatives of the (dihydro)phenanthrene phytochemical classes were able to directly activate AMPK, avoiding the risk of misinterpretation of results based on analysis of a single compound alone.

Nanostructures and multi-scale aggregation of high ion exchange capacity short-side-chain perfluorosulfonic acid dispersion.

Short-side-chain perfluorosulfonic acid (SSC-PFSA) ionomers with high ion-exchange-capacity are promising candidates for high-temperature proton exchange membranes (PEMs) and catalyst layer (CL) binders. The solution-casting method determines the importance of SSC-PFSA dispersion characteristics in shaping the morphology of PEMs and CLs. Therefore, a thorough understanding of the chain behavior of SSC-PFSA in dispersions is essential for fabricating high-quality PEMs and CLs. In this study, we have employed multiple characterization techniques, including dynamic light scatting (DLS), small-angle X-ray scattering (SAXS), and cryo-transmission electron microscope (Cryo-TEM), to fully study the chain aggregation behaviors of SSC-PFSA in water-ethanol solvents and elucidate the concentration-dependent self-assembly process. In dilute dispersions (2 mg/mL), SSC-PFSA assembles into mono-disperse rod-like aggregates, featuring a twisted fluorocarbon backbone that forms a hydrophobic stem, and the sulfonic acid side chains extending outward to suit the hydrophilic environment. As the concentration increases, the radius of rod particles increases from 1.47 to 1.81 nm, and the mono-disperse rod particles first form a "end-to-end" configuration that doubles length (10 mg/mL), and then transform into a swollen network structure in semi-dilute dispersion (20 mg/mL). This work provides a well-established structure model for SSC-PFSA dispersions, which is the key nanostructure to be inherited by PEMs.

Understanding the origins of reversible and hysteretic pathways of adsorption phase transitions in metal-organic frameworks.

Phase behavior of nanoconfined fluids adsorbed in metal-organic frameworks is of paramount importance for the design of advanced materials for energy and gas storage, separations, electrochemical devices, sensors, and drug delivery, as well as for the pore structure characterization. Phase transformations in adsorbed fluids often involve long-lasting metastable states and hysteresis that has been well-documented in gas adsorption-desorption and nonwetting fluid intrusion-extrusion experiments. However, theoretical prediction of the observed nanophase behavior remains a challenging problem. The mesoscopic canonical, or mesocanonical, ensemble (MCE) is devised to study the nanophase behavior under conditions of controlled fluctuations to stabilize metastable and labile states. Here, we implement and apply the MCE Monte Carlo (MCEMC) simulation scheme to predict the origins of reversible and hysteric adsorption phase transitions in a series of practical MOF materials, including IRMOF-1, ZIF-412, UiO-66, Cu-BTC, IRMOF-74-V, VII, and IX. The MCEMC method, called the gauge cell method, allows to produce Van der Waals type isotherms with distinctive swings around the phase transition regions. The constructed isotherms determine the positions of phase equilibrium and spinodals, as well as the nucleation barriers separating metastable states. We demonstrate the unique capabilities of the MCEMC method in quantitative predictions of experimental observations compared with the conventional grand canonical and canonical ensemble simulations. The MCEMC method is implemented in the open-source RASPA and LAMMPS software packages and recommended for studies of adsorption behavior and pore structure characterization of MOFs and other nanoporous materials.

Structural Characterization of Polygonatum Cyrtonema Polysaccharide and Its Immunomodulatory Effects on Macrophages.

A neutral Polygonatum cyrtonema polysaccharide (NPCP) was isolated and purified from Polygonatum cyrtonema by various chromatographic techniques, including DEAE-52 and Sephadex-G100 chromatography. The structure of NPCP was characterized by HPLC, HPGPC, GC-MS, FT-IR, NMR, and SEM. Results showed that NPCP is composed of glucose (55.4%) and galactose (44.6%) with a molecular weight of 3.2 kDa, and the sugar chain of NPCP was →1)-α-D-Glc-(4→1)-ß-D-Gal-(3→. In vitro bioactivity experiments demonstrated that NPCP significantly enhanced macrophages proliferation and phagocytosis while inhibiting the M1 polarization induced by LPS as well as the M2 polarization induced by IL-4 and IL-13 in macrophages. Additionally, NPCP suppressed the secretion of IL-6 and TNF-α in both M1 and M2 cells but promoted the secretion of IL-10. These results suggest that NPCP could serve as an immunomodulatory agent with potential applications in anti-inflammatory therapy.

Extraction, characterization and intestinal anti-inflammatory and anti-oxidative activities of polysaccharide from stems and leaves of Chuanminshen violaceum M. L. Sheh & R. H. Shan.

ETHNOPHARMACOLOGICAL RELEVANCE: Chuanminshen violaceum M. L. Sheh & R. H. Shan (CV) is used as a medicine with roots, which have the effects of benefiting the lungs, harmonizing the stomach, resolving phlegm and detoxifying. Polysaccharide is one of its main active components and has various pharmacological activities, but the structural characterization and pharmacological activities of polysaccharide from the stems and leaves parts of CV are still unclear. AIM OF THE STUDY: The aim of this study was to investigate the optimal extraction conditions for ultrasound-assisted extraction of polysaccharide from CV stems and leaves, and to carry out preliminary structural analyses, anti-inflammatory and antioxidant effects of the obtained polysaccharide and to elucidate the underlying mechanisms. MATERIALS AND METHODS: The ultrasonic-assisted extraction of CV stems and leaves polysaccharides was carried out, and the response surface methodology (RSM) was used to optimize the extraction process to obtain CV polysaccharides (CVP) under the optimal conditions. Subsequently, we isolated and purified CVP to obtain the homogeneous polysaccharide CVP-AP-I, and evaluated the composition, molecular weight, and structural features of CVP-AP-I using a variety of technical methods. Finally, we tested the pharmacological activity of CVP-AP-Ⅰ in an LPS-induced model of oxidative stress and inflammation in intestinal porcine epithelial cells (IPEC-J2) and explored its possible mechanism of action. RESULTS: The crude polysaccharide was obtained under optimal extraction conditions and subsequently isolated and purified to obtain CVP-AP-Ⅰ (35.34 kDa), and the structural characterization indicated that CVP-AP-Ⅰ was mainly composed of galactose, galactose, rhamnose and glucose, which was a typical pectic polysaccharide. In addition, CVP-AP-Ⅰ attenuates LPS-induced inflammation and oxidative stress by inhibiting the expression of pro-inflammatory factor genes and proteins and up-regulating the expression of antioxidant enzyme-related genes and proteins in IPEC-J2, by a mechanism related to the activation of the Nrf2/Keap1 signaling pathway. CONCLUSION: The results of this study suggest that the polysaccharide isolated from CV stems and leaves was a pectic polysaccharide with similar pharmacological activities as CV roots, exhibiting strong anti-inflammatory and antioxidant activities, suggesting that CV stems and leaves could possess the same traditional efficacy as CV roots, which is expected to be used in the treatment of intestinal diseases.

Skin healthcare protection with antioxidant and anti-melanogenesis activity of polysaccharide purification from Bletilla striata.

In this study, we investigated the structural characterization and biological activities of Bletilla striata polysaccharides (BSPs) for their role as antioxidants and anti-melanogenesis agents in skin healthcare protection. Three neutral polysaccharides (BSP-1, BSP-2, and BSP-3) with molecular weights of 269.121 kDa, 57.389 kDa, and 28.153 kDa were extracted and purified. Their structural characteristics were analyzed by ion chromatography, GC-MS, and 1D/2D NMR. The results showed that BSP-1, which constitutes the major part of BSPs, was composed of α-D-Glcp, ß-D-Glcp, ß-D-Manp, and 2-O-acetyl-ß-D-Manp, with the branched-chain accompanied by ß-D-Galp and α-D-Glcp. BSP-1, BSP-2, and BSP-3 can enhance the total antioxidant capacity of skin fibroblasts with non-toxicity. Meanwhile, BSP-1, BSP-2, and BSP-3 could significantly inhibit the proliferative activity of melanoma cells. Among them, BSP-1 and BSP-2 showed more significance in anti-melanogenesis, tyrosinase inhibition activity, and cell migration inhibition. BSPs have effective antioxidant capacity and anti-melanogenesis effects, which should be further emphasized and developed as skin protection components.

Structural characterization of a glycoprotein from white jade snails (Achatina Fulica) and its wound healing activity.

Snail mucus is rich in proteins and polysaccharides, which has been proved to promote wound healing in mice in our previous research. The aim of this study was to investigate the effective component in snail mucus that can exert the wound healing potential and its structural characterization. Here, the glycoprotein from the snail mucus (SM1S) was obtained by DEAE-Sepharose Fast Flow and Sephacryl S-300 columns. The structural characteristics of SM1S were investigated via chromatographic techniques, periodic acid oxidation, FT-IR spectroscopy and NMR spectroscopy. Results showed that SM1S was a glycoprotein with a molecular weight of 3.8 kDa (83.23 %), consists of mannose, glucuronic acid, glucose, galactose, xylose, arabinose, fucose at a ratio of 13.180:4.875:1043.173:7.552:1:3.501:2.058. In addition, the periodic acid oxidation and NMR analysis showed that SM1S contained 1,6-glycosidic bonds, and might also contain 1 â†’ 4 and 1 â†’ 2 glycosidic or 1 â†’ 3 glycosidic bonds. Furthermore, the migration experiment of human skin fibroblasts in vitro suggested that SM1S had a good effect to accelerate the scratch healing of cells. This study suggested that SM1S may be a prospective candidate as a natural wound dressing for the development of snail mucus products.

Structure characterization of an agavin-type fructan isolated from Polygonatum cyrtonema and its effect on the modulation of the gut microbiota in vitro.

The herbal medicine Polygonatum cyrtonema is highly regarded in China for its medicinal and dietary properties. However, further research is needed to elucidate the structure of its polysaccharide and understand how it promotes human health by modulating the gut microbiota. This study aims to investigate a homogeneous polysaccharide (PCP95-1-1) from Polygonatum cyrtonema and assess its susceptibility to digestion as well as its utilization by intestinal microbiota. The results confirmed that PCP95-1-1 is an agavin-type fructan, which possesses two fructose chains, namely ß-(2 â†’ 6) and ß-(2 â†’ 1) fructosyl-fructose, attached to the sucrose core, and has branches of ß-D-Fruf residues. Moreover, PCP95-1-1 demonstrated resistance to digestion and maintained its reducing sugar content throughout the digestive system, indicating it could reach the gut without being digested. In vitro fermentation of PCP95-1-1 significantly decreased the pH value (p < 0.05) while notably increasing the production of short-chain fatty acids (SCFAs), confirming its utilization by human gut microbiota. Additionally, PCP95-1-1 exhibited a significant ability (p < 0.05) to beneficial bacteria such as Megamonas and Bifidobacterium, while reducing the presence of facultative or conditional pathogens such as Escherichia-Shigella and Klebsiella at the genus level. Consequently, PCP95-1-1 has the potential to positively influence physical well-being by modulating the gut microbiota environment and can be developed as a functional food.