Immunomodulatory Activity Of Polysaccharides Research Articles

Optimization of Extraction Process, Structure Characterization, and Immunomodulatory Activity of Polysaccharides from Black Garlic

AbstractUltrasound assisted extraction (UAE) was used to extract polysaccharides from black garlic, and the extraction process for UAE of black garlic polysaccharides (BGPs) was optimized via RSM coupled with genetic algorithm. The optimal extraction process parameters were obtained as follows: extraction time of 30 min, liquid‐to‐solid ratio of 29 mL/g, extraction temperature of 51 ℃, and ultrasound power of 418 W, and the yield of BGPs was 10.17% ± 0.14%. Subsequently, the crude BGPs were further purified by DEAE‐52 cellulose and Sephadex G‐100 to obtain a homogeneous fraction (BGPs‐1‐SG with the molecular weight of 1.37 × 106 Da) that was comprised of mannose (Man), glucuronic acid (GlcA), rhamnose (Rha), glucose (Glc), and fucose (Fuc) with a molar ratio of 40.23:71.06:2.96:85.38:7.32. Congo red and circular dichroism spectroscopy indicate that BGPs‐1‐SG has a triple helix structure. Scanning electron microscope and atomic force microscope demonstrate that BGPs‐1‐SG showed irregular structures including sheet‐like, rod‐shaped, irregular spherical structures, and aggregated in aqueous solutions. Moreover, BGPs‐1‐SG could increase viability, phagocytic rate, and NO content of RAW264.7 cells. Furthermore, BGPs‐1‐SG could promote the secretion and mRNA expression levels of IL‐1β, IL‐6, and TNF‐α. The findings can provide an important reference for the development of functional foods.

Structural Characterization and Immunomodulatory Activity of Polysaccharides from Polygonatum sibiricum Prepared with Deep Eutectic Solvents

Deep eutectic solvents (DES), as a new, efficient, and green solvents, have attracted more attention in recent years. This study was performed to extract Polygonatum sibiricum polysaccharides using DES (DPSP). Subsequently, DPSP was subjected to DEAE-Sepharose Fast Flow and Sephadex G-100 column for further purification (DPSP-3). Structural characterization and immunomodulatory activity in RAW264.7 cells were performed. Results showed that the yield of DPSP was (15.62 ± 0.71)%, and its yield was 1.53 times that of the polysaccharides extracted using the pharmacopoeia method (PSP). DPSP-3 had a smaller molecular weight (3.2 × 106 Da) and a higher ratio of galactose (65.75%) and mannose (19.76%) as compared to PSP. The scanning electron microscope (SEM) showed that DPSP-3 had curly shape, lamellar surface, and a few spherical edges, which were significantly different from PSP and DPSP. Both PSP and DPSP-3 could significantly improve phagotrophic capacity and increase the release of ROS, NO, IL-6, and TNF-α in RAW 264.7 cells, and DPSP-3 had better immunomodulatory activity. In summary, compared to the pharmacopoeia method, polysaccharides prepared using the DES extraction method showed higher yield and improved immunomodulatory activity.

Antioxidant and Immunomodulatory Activities of Polysaccharides from Fermented Wheat Products of Grifola frondosa: In Vitro Methods.

Despite the well-known health benefits of Grifola frondosa, there is a lack of understanding regarding the potential antioxidant and immunomodulatory properties of different varieties when fermented with wheat grains. We aimed to explore the potential of G. frondosa-fermented wheat flour as a functional food. Three varieties of G. frondosa (GFA, GFB, and GFC) were fermented with wheat grains for solid-state fermentation. Polysaccharides were extracted and analyzed for total sugar content, monosaccharide composition, Mw profile, antioxidant activity, cytotoxicity, and immunomodulatory properties. Results were evaluated using HPLC, DPPH assay, MTS assay, Griess reagent, and ELISA method. Our study found variations in three different varieties of G. frondosa-fermented wheat polysaccharides. Glucose was the predominant monosaccharide, followed by galactose and mannose. Each variety had a different molecular weight distribution, with GFA-wheat mainly present in fraction II, GFB-wheat in fraction I, and GFC-wheat in fraction III. At a concentration of 1.25 mg/mL, GFA-wheat and GFB-wheat polysaccharides increased DPPH scavenging ability by 76.8% and 58.7%, respectively. The polysaccharides showed no apparent toxic effect and enhanced the production of NO, IL-6, and TNF-α in RAW 246.7 macrophages. GFB-wheat polysaccharides demonstrated remarkable immunomodulatory properties at a concentration of 5 μg/mL. Our study provides a theoretical basis for using G. frondosa in wheat staple agricultural products to improve human health.

Impacts of sulfur fumigation on the chemistry and immunomodulatory activity of polysaccharides in ginseng

Ginseng is widely regarded as a panacea in Oriental medicine mainly due to its immunomodulatory activity. We previously found that sulfur fumigation, a commonly used pesticidal and anti-bacterial processing practice, weakened the immunomodulatory activity of ginseng. However, if and how sulfur fumigation affects the polysaccharides in ginseng, the crucial components contributing to the immunomodulatory function, remain unknown. Here we report that polysaccharides extracted from sulfur-fumigated ginseng (SGP) presented different chemical properties with polysaccharides extracted with non-fumigated ginseng (NGP), particularly increased water extraction yield and decreased branching degree. SGP had weaker immunomodulatory activity than NGP in immunocompromised mice, as evidenced by less improved immunophenotypes involving body weight, immune organ indexes, white blood cells, lymphocyte cell populations and inflammation. The different immunomodulatory activities were accompanied by changes in the interaction between the polysaccharides and gut microbiota, in which SGP stimulated the growth of different bacteria but produced less SCFAs as compared to NGP. Fecal microbiota transplantation experiment suggested that gut microbiota played a central role in causing the weakened immunomodulatory activity in vivo. This study provides definite evidence that sulfur fumigation affects the chemistry and bioactivity of ginseng polysaccharides, thereby contributing to understanding how sulfur fumigation weakens the immunomodulatory activity of ginseng.

Basic characterization, antioxidant and immunomodulatory activities of polysaccharides from sea buckthorn leaves

The polysaccharides from Sea buckthorn leaves (SBLPs) were extracted by hot water and purified by DEAE cellulose, then separated into six polysaccharides (SBLP-S) by DEAE-52 column. Six separated polysaccharides were characterized by Ultraviolet Spectroscopy, Infrared Spectrum, High Performance Liquid Chromatographic and Congo red analysis. The antioxidant activity and immunological activity were investigated in vitro. The results revealed that the monosaccharide composition of SBLP-S-1, SBLP-S-2, SBLP-S-3, SBLP-S-5 and SBLP-S-6 contained Man, GlcN, Rib, Rha, GluA, GalA, Glu, Gal, Xyl, Ara and Fuc, among them, rare glucosamine was found. And SBLP-S-4 contained all above components except GlcN and GluA. FT-IR showed that SBLP-S were sulfated polysaccharide containing uronic acid. Molecular weights of SBLP-S were 338.659, 401.305, 599.849, 393.904, 626.895 and 176.862 kDa. The Congo-red test indicated that SBLP-S-2, SBLP-S-4, SBLP-S-5, and SBLP-S-6 had triple helix conformation. Crude polysaccharides had the strong scavenging activities on DPPH radicals, ABTS radicals and hydroxyl radicals. The six polysaccharides had the activity of immune stimulation on RAW264.7 cell. SBLP-S-2 promoted the phagocytosis best and SBLP-S-6 promoted the NO production best. The results suggested that SBLPs could be used as potential antioxidants and immunomodulatory agents in pharmaceutical and functional food fields.

Comparison of physicochemical characteristics, antioxidant and immunomodulatory activities of polysaccharides from wine grapes

In this study, an efficient ultrasonic-assisted extraction method was used for the extraction and optimization of four wine grape polysaccharides. A three-level, three-factor Box Behnken Design combined with the response surface approach was used to optimize the extraction conditions. Their physicochemical properties, molecular structure, antioxidant activity, immunomodulatory activity and hepatoprotective effects were examined and compared. These findings suggest that the four wine grape polysaccharides share similar basic structural features and monosaccharide composition. Furthermore, four wine grape polysaccharides exhibited antioxidant and immunomodulatory activities in a concentration-dependent manner. Moldova (MD) polysaccharide displayed better antioxidant activity and immunomodulatory ability. Furthermore, MD polysaccharide has a significant therapeutic effect on CCl4-induced rat liver injury by improving the antioxidant defense system and inhibiting oxidative stress, indicating that MD has a hepatoprotective effect. Taken together, the MD wine grape polysaccharide may have potential applications in prevention of liver disease in the functional food and pharmaceutical industries.

Immunomodulatory activity of polysaccharide from Trametes gibbosa (Pers.) Fr (Basidiomycota, Fungi) mediated by TLR4 signaling pathway

Background: Trametes species possess remarkable immunomodulatory and anticancer effects which are mainly related to the activation of innate immune receptors by their polysaccharide constituents. In this study, we investigate the effect of Trametes gibbosa (Pers.) Fr. polysaccharide fraction (TGP) on activation of TLR-4 receptor and subsequent release of IL-8 in HEK-Blue™ hTLR4 cells.Materials and Methods: The polysaccharide fraction was purified using ethanol precipitation and dialysis methods. The total sugar content and monosaccharide composition were analyzed by phenol–sulfuric acid and chromatographic methods. FT-IR spectroscopy was also performed for structure characterization of the polysaccharide. The activation of TLR4 was determined by measuring the secreted embryonic alkaline phosphatase in the culture media.Results: The results indicated that the total sugar content of TGP was about 90%, which glucose was the major constituents. FT-IR analysis showed the characteristic bands of polysaccharides. TGP was able to activate the TLR-4 signaling pathway in a dose-dependent manner. Moreover, the significant increase of IL-8 was observed in cells treating with TGP. The HEK-Blue Null2™ reporter cells lacking TLR4, did not respond to LPS and TGP.Conclusion: The results suggest that TLR4 signaling cascade serve as targets for immunomodulatory activity of T. gibbosa which could address the anticancer properties of Trametes species.

Natural Deep Eutectic Solvent-Assisted Extraction, Structural Characterization, and Immunomodulatory Activity of Polysaccharides from Paecilomyces hepiali.

Polysaccharides, which can be affected by different preparations, play a crucial role in the biological function of Paecilomyces hepiali (PHPS) as a health food. To explore high-valued polysaccharides and reduce the negative influence of human involvement, a green tailorable deep eutectic solvent (DES) was applied to optimize the extraction of polysaccharides (PHPS-D), followed by the evaluation of the structural properties and immunomodulation by comparison with the hot-water method (PHPS-W). The results indicated that the best system for PHPS-D was a type of carboxylic acid-based DES consisting of choline chloride and succinic acid in the molar ratio of 1:3, with a 30% water content. The optimal condition was as follows: liquid-solid ratio of 50 mL/g, extraction temperature of 85 °C, and extraction time of 1.7 h. The actual PHPS-D yield was 12.78 ± 0.17%, which was obviously higher than that of PHPS-W. The structural characteristics suggested that PHPS-D contained more uronic acid (22.34 ± 1.38%) and glucose (40.3 ± 0.5%), with a higher molecular weight (3.26 × 105 g/mol) and longer radius of gyration (78.2 ± 3.6 nm), as well as extended chain conformation, compared with PHPS-W, and these results were confirmed by AFM and SEM. Immunomodulatory assays suggested that PHPS-D showed better performance than PHPS-W regarding pinocytic activity and the secretion of NO and pro-inflammatory cytokines (IL-6, TNF-α and IL-1β) by activating the corresponding mRNA expression in RAW264.7 cells. This study showed that carboxylic acid-based DES could be a promising tailorable green system for acidic polysaccharide preparation and the valorization of P. hepiali in functional foods.

Immunomodulatory effect of polysaccharides isolated from Lonicera japonica Thunb. in cyclophosphamide-treated BALB/c mice

Lonicera japonica (L. japonica) is utilized as foods and healthy drink around the world. Until now, the immunomodulatory activity of polysaccharides from L. japonica (LJP) is little studied. In our previous work, LJP was fractionated to a neutral component (LJP-N) and an acidic component (LJP-A) by a DEAE-Cellulose column, and LJP-N was a starch-like polysaccharide and LJP-A was a pectic polysaccharide. In this study, LJP-N and LJP-A were investigated for their immunomodulatory effect, and the protective effect of these two polysaccharide fractions against immune injury by cyclophosphamide (CTX) in BALB/c mice was evaluated. Results showed that when compared with CTX group, LJP fractions, especially for LJP-A (200 mg kg−1) can enhance the immune function, improve atrophy of the lymphoid organs thymus and spleen (the increased approximately 1.8- and 1.6-fold), increase the phagocytic function of macrophages (increased approximately 1.7-fold), increase the secretion of cytokines (the levels of IL-6, IL-2, and TNF-α increased approximately 2.5-, 2.0-, and 1.4-fold) and immunoglobulins levels (the levels of IgM and IgG increased approximately 1.2- and 1.7-fold) in serum, and enhance the cytotoxic activity of NK cells (increased approximately 3.5-fold). Taken together, the present results suggest that LJP-A, rich in uronic acid, with a molecular weight of 400 kDa, may be a potential candidate as the functional foods.

The Structural Characterization and Immunomodulatory Activity of Polysaccharides from Pleurotus abieticola Fruiting Bodies.

Polysaccharides obtained from mushrooms have been reported to possess immunomodulatory properties. In this study, a water-soluble polysaccharide was purified from the fruiting bodies of Pleurotus abieticola, entitled PAPS1. After its composition and structural analysis, the immunomodulatory activity was investigated in immunosuppressed mice induced by cyclophosphamide (CTX) at a dosage of 70 mg/kg by intraperitoneal injection for 7 days. After 28 days of intragastric administration, PAPS1 alleviated cyclophosphamide (CTX)-induced histopathological damage and increased the expressions of splenic CD4, CD8, CD56 and IgM in the serums of immunosuppressed mice. PAPS1 suppressed the oxidative stress indicated by preventing the increases in ROS and MDA levels. According to the intestinal microflora analysis, PAPS1 regulated 11 bacteria at the gene level, including Helicobacter and Paraprevotella, which are related to immunity and oxidative capacity. Compared with CTX-treated mice, significant increases in immune-related cytokines, such as interleukin (IL)-2, IL-6 and IL-12 in the serums of mice treated with PAPS1, were observed. Finally, PAPS1 can strongly increase the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream proteins. In conclusion, PAPS1-boosted immunity may be related to its suppression on oxidative stress via enhancing the activity of Nrf2 signaling. Thus, PAPS1 can be investigated as a candidate for immunomodulatory therapy.

The variation on structure and immunomodulatory activity of polysaccharide during the longan pulp fermentation

In the current study, the effects of fermentation manners on the structure and immunomodulatory activity of polysaccharide in longan wine or vinegar were investigated. Compared to longan polysaccharide (CP1), polysaccharide in longan wine (CP2) or vinegar (CP3 and CP4) had smaller molecular weights, and was consisted of more mannose, arabinose, rhamnose, galactose and less glucose. After purification, the major fraction (P1-P4) was obtained from CP1-CP4, respectively. The structures and immunoregulatory activities of P1-P4 were characterized. Fermentation and purification were favorable to increase the immunoregulatory activities of P2-P4, which were contributed to their different structural features. The structure-activity relationship analysis indicated that molecular weight, mannose, rhamnose, glucuronic acid, glucose and arabinose were significantly associated with the cytokines secretion. Compared with other polysaccharides, P3 displayed better immunomodulatory activity due to its lower molecular weight, lower contents of rhamnose and glucose, and higher levels of mannose and arabinose by activating MAPK and PI3K/Akt signaling pathways.

Gas chromatography (GC) fingerprinting and immunomodulatory activity of polysaccharide from the rhizome of Menispermum dauricum DC.

This research aimed to establish the gas chromatography (GC) fingerprints and examine the immunomodulatory activity of the rhizome of Menispermum dauricum polysaccharides. In this study, the preparation conditions were optimized by the response surface method (RSM). GC is an effective and sensitive technique employed to measure the composition of monosaccharides; the GC fingerprints of total polysaccharides from 10 batches of the rhizome of M. dauricum (tMDP) were established, and chemometrics methods were adopted to examine the differences and similarities of tMDP from distinct regions. The similarity evaluation illustrated that the polysaccharides derived from the rhizome of M. dauricum from different origins were highly similar. The results of principal components analysis (PCA) illustrated that all the tMDPs may be integrated into one group within the 95% confidence interval, but the rhizome of M. dauricum from different origins could also be distinguished in the plot of PCA scores. Then, the major bioactive fraction MDP was purified and obtained by column chromatography. Our previous study showed that MDP exhibited significant immunomodulatory activity, but the mechanism of the in vitro immunomodulatory activity of MDP is unclear. The macrophage activation induced by MDP was abolished when Toll-like receptor 4 (TLR4) signaling was knocked down by the TLR4 inhibitor. Furthermore, western blot analysis illustrated that MDP activated RAW264.7 cells through MAPKs and NFκB pathways induced by TLR4. This research offers a theoretical foundation for quality control and additional study as a potential immunomodulator of MDP.

Composition and immunomodulatory activity of neutral and acidic polysaccharides isolated from Epimedii Folium

Epimedii Folium possesses many pharmacological activities including immunomodulation, anti-oxidation, and anti-tumor. Polysaccharides are the main components of Epimedii Folium, and their activities are closely related to the structure. The present study isolated a neutral polysaccharide(EPS-1-1) and an acidic polysaccharide(EPS-2-1) from the aqueous extract of Epimedii Folium through DEAE-52 cellulose anion-exchange chromatography and Sephadex G-100. The structures were characterized by chemical composition analysis, high-performance gel permeation chromatography(HPGPC), Fourier-transform infrared spectrometry(FT-IR), 1-phenyl-3-methyl-5-pyrazolone(PMP) derivatization, scanning electron microscopy(SEM), Congo red test, etc. The immunomodulatory activity of polysaccharides in vitro was determined by investigating the effects on the maturation of bone marrow-derived dendritic cells(BMDCs) and the release of inflammatory cytokines. According to the structural characterization analysis, EPS-1-1 was composed of fructose(Fuc), mannose(Man), ribose(Rib), rhamnose(Rha), glucose(Glc), galactose(Gal), xylose(Xyl), and arabinose(Ara) at 1.90∶0.67∶0.05∶0.08∶3.29∶1.51∶0.05∶0.37(molar ratio), while EPS-2-1 was mainly composed of Fuc, Man, Rha, glucuronic acid(GlcA), galacturonic acid(GalA), Glc, Gal, Xyl, and Ara at 5.25∶0.18∶0.32∶0.13∶1.14∶0.16∶0.55∶0.08∶0.2. EPS-1-1 and EPS-2-1 could promote the maturation and function of BMDCs through up-regulating the expression of MHC-Ⅱ, CD86, CD80, and CD40, and increasing the levels of inflammatory cytokines(IL-6, IL-12, and TNF-α) in vitro experiments, which suggested that EPS-1-1 and EPS-2-1 possessed good immunomodulatory activity.

Isolation, characterisation and complement fixation activity of acidic polysaccharides from Argemone mexicana used as antimalarials in Mali

Context Global studies on Argemone mexicana L. (Papaveraceae) traditionally used against malaria in Mali are limited to its low-mass compounds activities, and little information on its bioactive polysaccharides is available. Objective This study determines the structure and the immunomodulatory activity of polysaccharides from aerial parts of A. mexicana. Materials and methods Acidic polysaccharides from this plant material named HMAmA1 and HMAmA2 were isolated from water extracts. Their monosaccharide composition was determined by gas chromatography. Glycosidic linkages were determined using GC-MS. NMR was also applied. The polymers were tested for effects on the human complement system in vitro at different doses. Results The monosaccharide composition showed that the two polysaccharides contained in different amounts the following monomers: arabinose, rhamnose, galactose, and galacturonic acid. Overall structural analysis showed the presence of a low ratio of 1,2-linked rhamnose compared to 1,4-linked galacturonic acid with arabinogalactans substituted on position 4 of rhamnose. NMR data showed the presence of galacturonans alternated by rhamnogalacturonans bearing arabinose and galactose units. α-Linkages were found for l-arabinose, l-rhamnose and d-galacturonic acid, while β-linkages were found for d-galactose. The two polysaccharides exhibited strong complement fixation activities, with HMAmA1 being the highest potent fraction. ICH50 value of HMAmA1 was 5 µg/mL, compared to the control BPII being 15.9 µg/mL. Discussion and conclusions Polysaccharides form A. mexicana presented a complement fixation effect. The complement system is an important part of the immune defense, and compounds acting on the cascade are of interest. Therefore, these polymers may be useful as immunodulatory agents.

Preparation, characterization and immunoregulatory activity of derivatives of polysaccharide from Atractylodes lancea (Thunb.) DC

A polysaccharide (ALP-1) extracted from Atractylodes lancea (Thunb.) DC. was carboxymethylated (C-ALP-1), phosphorylated (P-ALP-1) and acetylated (A-ALP-1) to improve its physicochemical properties and bioactivities. The solubility of all derivatives was increased, and the solubility of A-ALP-1 increased to 137.5 mg/mL, which was much higher than the solubility of ALP-1 (15.0 mg/mL). The results of HPSEC-MALLS-RID showed that the molecular weight of polysaccharides was slightly increased after the modification, and the root mean square radius of rotation (Rz) and morphology of polysaccharides in solution were also changed. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) results confirmed that the surface morphology of ALP-1 changed dramatically and the crystallinity decreased after structural modification. From thermal analysis results, the T50 of ALP-1, C-ALP-1, P-ALP-1 and A-ALP-1 were 281.34, 292.14, 333.75 and 298.70 °C, which showed that derivatives had stronger thermal stability than ALP-1. The immunomodulatory activity studies displayed that P-ALP-1 showed the best ability to stimulate RAW264.7 macrophages to release NO, and A-ALP-1 showed the best capacity to stimulate TNF-α and IL-6 releasing. These results indicated that chemical modification could enhance the solubility, the thermal stability and immunomodulatory activity of polysaccharides, which is beneficial for the development and utilization of natural polysaccharides.

Changes of Physicochemical Properties and Immunomodulatory Activity of Polysaccharides During Processing of Polygonum multiflorum Thunb.

The roots of Polygonum multiflorum Thunb (PM) have a long history of usage in traditional Chinese medicine and are still widely utilized today. PM in raw or processed form has different biological activities and is commonly used to treat different diseases. Polysaccharides are the main component of PM, and it is unclear whether their physicochemical properties and activities change after processing. In this study, the polysaccharides from thirty-one raw PM (RPMPs) and nine processed PM (PPMPs) were extracted, and the physicochemical properties and immunomodulatory activity in vitro of polysaccharide samples were evaluated. Results showed that RPMPs and PPMPs had significant differences in physicochemical properties. RPMPs and PPMPs were both composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, and arabinose. However, RPMPs and PPMPs had significant differences in their yields, molecular weight (Mw), and the molar ratio of Glc/GalA (p < 0.05), which can be used to distinguish raw and processed PM. The fingerprint of monosaccharide composition was analyzed by chemometrics, and it was further demonstrated that Glc and GalA could be used as differential markers. The immunomodulatory activity assays indicated that RPMPs and PPMPs could significantly enhance phagocytosis and mRNA expression of cytokines in RAW 264.7 cells. In addition, the immunomodulatory activity of PPMPs with lower Mw was significantly better than that of RPMPs. This study furthers the understanding of the polysaccharides from raw and processed PM and provides a reference for improving the quality standard of PM.

Immunomodulatory activity of polysaccharides from the mycelium of Aspergillus cristatus, isolated from Fuzhuan brick tea, associated with the regulation of intestinal barrier function and gut microbiota

Aspergillus cristatus is the dominant fungus involved in the fermentation of Fuzhuan brick tea (FBT). The intracellular polysaccharides (IPSs) from A. cristatus (MK346334, NCBI), isolated from FBT, exhibited immunomodulatory activity in vitro while the effects in vivo on immune system and gut microbiota remain unclear. In this study, IPSs and the purified fraction (IPSs-2) from IPSs were prepared and their immunomodulatory activities were investigated with cyclophosphamide (Cy)-induced immunosuppressive mice. As results, IPSs strengthened the immune function, manifesting in the improvement of body weight, daily intake, immune organ indices, cytokines and immunoglobulin. Meanwhile, IPSs attenuated Cy-induced intestinal barrier injury and promoted the expression of tight junction proteins and mucin, reinforcing the intestinal barrier function. Moreover, IPSs not only promoted the production of short-chain fatty acids and the expression of G protein-coupled receptor (GPR), but also balanced dysbiosis of gut microbiota through elevating the growth of beneficial bacteria while reducing pathobionts to maintain the homeostasis of the microbial ecology. These results suggested that IPSs exerted immunomodulatory activity linking with the restoration of intestinal barrier function and regulation of gut microbiota, which contributes to the development of novel probiotics and effective immunomodulators for strengthening host immunity and gut health.

Structural Characterization and Immunomodulatory Activities of Polysaccharides from Suillus granulatus

The present study was aimed to investigate the structural characteristics and immunomodulatory activity of Suillus granulatus polysaccharides. Two polysaccharide fractions(SGP3-1 and SGP3-2) were purified from the fruiting bodies of Suillus granulatus by water extraction and alcohol precipitation, deproteinization, and column chromatography separation. The physicochemical properties of SGP3-1 and SGP3-2 were characterized by high-performance gel permeation chromatography(HPGPC), high-performance liquid chromatography(HPLC), Fourier transform infrared spectroscopy(FT-IR), nuclear magnetic resonance spectroscopy(NMR), X-ray diffraction(XRD), etc. The results showed that the weight-average molecular weight of SGP3-1 and SGP3-2 were 170.48 kDa and 14.52 kDa, respectively. Both SGP3-1 and SGP3-2 were low-crystallinity amorphous polymers, and had no triple-helix conformation. Additionally, SGP3-1 characterized by α-type glycosidic linkage was mainly composed glucose(55.47%), mannose(20.63%) and galactose(14.04%), while SGP3-2 characterized by β-type glycosidic linkage was mainly composed of glucose(82.43%). The results from RAW264.7 cells in vitro suggested that SGP3-1 and SGP3-2 showed no cytotoxicity in the concentration range from 5 to 40 μg/mL. Moreover, SGP3-1 and SGP3-2 could significantly enhance the phagocytic activity and promote the production of nitric oxide(NO), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) through activating mitogen-activated protein kinases(MAPKs), phosphatidylinositol-3-kinase(PI3K)/Akt, and nuclear factor-κB(NF-κB) signaling pathways. Furthermore, SGP3-2 exhibited better immunomodulatory activity than SGP3-1. It showed that SGP3-1 and SGP3-2 could be used to develop functional foods, as dietary supplements for people with low immunity, and provide a theoretical basis and research basis for the further development of Boletus edulis.

Structural elucidation, anti-radical and immunomodulatory activities of polysaccharides from the roots of Glehnia littoralis

This study investigated the structural elucidation, anti-radical and immunomodulatory activities of polysaccharides from the roots of Glehnia littoralis. A crude polysaccharide was extracted from the roots of G. littoralis through the ultrasonic-assisted extraction and further purified by DEAE-52 cellulose and Sephadex G-100 gel column, a major polysaccharide fraction named GLP80-1 was obtained. The chemical properties and structure of GLP and GLP80-1 were characterized by acid hydrolysis, methylation analysis, along with high performance gel permeation chromatography, Fourier transform infrared, nuclear magnetic resonance, scanning electron microscope, thermogravimetric analysis and X-ray diffraction. The molecular weight distributions of GLP were determined as 1.89 × 106 and 1.26 × 104 Da. The monosaccharide composition of GLP was glucose, glucuronic acid, galactose and arabinose with molar ratios of 0.91:0.04:0.03:0.02, respectively. The average molecular weight of GLP80-1 was determined as 1.63 × 104 Da. The structure of GLP80-1 was deduced to be a homogenous glucan, comprised a main chain of (1→4)-linked-α-D-Glcp with a single α-D-Glcp branch substituted at C-6. The results of biological activities in vitro showed that GLP and GLP80-1 exhibited free radical scavenging effects, and displayed promotion for the proliferation of mouse spleen lymphocytes and RAW264.7 cells. The data indicated that GLP and GLP80-1 had the potential to be explored as novel natural antioxidant and immunomodulator for application in functional food.

Purification, Characterization and Immunomodulatory Activities of Polysaccharides fromMulberryLeaf Fermented withPhellinus igniarius

Phellinus igniariusis a rare and precious medicinal fungus, displaying an outstanding physiological effect, especially the immunomodulatory effects. Previous studies indicated that water-soluble crude polysaccharide (MPFP) was obtained from mulberry leaf fermented withPhellinus igniarius. In vitrocell assay revealed that MPFP showed higher immunomodulatory activity than that of mulberry leaves polysaccharide (MP) andPhellinus igniariusmycelial polysaccharide (PP). Therefore, in this study, structure and immunomodulatory activity of MPFP were measured, a novel polysaccharide named MPFP2-1 was separated through DEAE-52 cellulose column and SephadexG-100 gel-filtration chromatography. Monosaccharide composition analysis showed that MPFP2-1 was mainly composed of L-rhamnose and D-glucose with the molar ratio of 1.0:5.4. The average molecular weight was 50.3 kDa by high performance gel permeation chromatography (HPGPC). FT-IR spectrum showed that MPFP2-1 contained a characteristic absorption peak of polysaccharide. The NMR spectrum indicated MPFP2-1 contained 1 → 6 glucosidic bond.In vitroimmunomodulatory assay revealed that MPFP2-1 significantly enhanced the macrophages proliferation, stimulated the macrophages phagocytic capacity, as well as induced NO and TNF-a generation. We further discovered that MPFP2-1 stimulated iNOS and TNF-αprotein expression in RAW264.7 cells by western blotting. The results are in agreement with ELISA. All the results suggest that MPFP2-1 possesses potent immunomodulatory activity and could be taken forward as new products for medicines.