Isolation, purification, structural characterization and immunostimulatory activity of water-soluble polysaccharides from Lepidium meyenii

Natural plant-derived polysaccharides targeting macrophage polarization: a promising strategy for cancer immunotherapy

Tumor associated macrophages (TAMs) are the predominant innate immune cells in the tumor microenvironment (TME). Cytokines induce the differentiation of macrophages into distinct types of TAMs, primarily characterized by two phenotypes: M1-polarized and M2-polarized. Cancer growth is suppressed by M1-polarized macrophages and promoted by M2-polarized macrophages. The regulation of macrophage M1 polarization has emerged as a promising strategy for cancer immunotherapy. Polysaccharides are important bioactive substances found in numerous plants, manifesting a wide range of noteworthy biological actions, such as immunomodulation, anti-tumor effects, antioxidant capabilities, and antiviral functions. In recent years, there has been a significant increase in interest regarding the immunomodulatory and anti-tumor properties of polysaccharides derived from plants. The regulatory impact of polysaccharides on the immune system is mainly associated with the natural immune response, especially with the regulation of macrophages. This review provides a thorough analysis of the regulatory effects and mechanisms of plant polysaccharides on TAMs. Additionally, an analysis of potential opportunities for clinical translation of plant polysaccharides as immune adjuvants is presented. These insights have greatly advanced the research of plant polysaccharides for immunotherapy in tumor-related applications.

Xylan acetate ester ameliorates ulcerative colitis through intestinal barrier repair and inflammation inhibition via regulation of macrophage M1 polarization

Ulcerative colitis (UC) is a chronic inflammatory disease resulting from abnormal immune response to gut microflora translocating through damaged intestinal barrier. Xylan acetate ester (XylA) can increase colon short-chain fatty acids (SCFAs) levels and alleviate kidney disease by inhibiting inflammation through the G protein-coupled receptor pathway. Here, we synthesized and purified XylA, and then the effects and mechanisms of XylA on dextran sodium sulfate-induced UC in mice were investigated. The results showed that in mice, similar to the positive drug 5-aminosalicylic acid, oral administration of XylA significantly alleviated all UC symptoms, including weight loss, diarrhea, and hematochezia. Further mechanism studies revealed that XylA could repair the damaged colon structure and intestinal barrier function by increasing the expression of tight junction protein zonula occludens 1 and occludin, thus reducing LPS penetration. Moreover, XylA could also restrain intestinal inflammation via inhibiting LPS-TLR4 pathway, downregulating M1 macrophage polarization, and reducing proinflammatory cytokines expression, and in vitro cell experiments showed that these effects may be mediated by XylA derived SCFAs, particularly acetates, propionates and butyrates. All these results suggested that XylA may be a potential improving agent for UC treatment, and natural polysaccharides may represent a novel avenue for drug development of UC.

Effect and mechanism of Tricholoma matsutake extract combined with bakuchiol and ergothioneine on UVB-induced skin aging

BACKGROUND

Aging is a physiological phenomenon in the process of life, and skin aging has a significant impact on human appearance. Therefore, the search for methods to delay skin aging is of great significance for improving the quality of human life.

MATERIALS AND METHODS

This study investigated the anti-photoaging effect of Tricholoma matsutake (T) extract composition combined with bakuchiol (B) and ergothioneine (E), and explored its potential mechanism through transcriptome, metabolomics, and network pharmacology.

RESULTS

57 main chemical components are identified from the ethanol extract of T. matsutake (T), including D-carnitine (24.55%), α,α-trehalose (15.56%), DL malic acid (8.99%), D-(-)-quinic acid (7.46%), erucamide (7.04%) and so on. After TBE treatment, inflammation of the mice dorsal skin is significantly minimized. Hematoxylin and eosin (H&E) staining and toluidine blue staining reveal that TBE has an anti-inflammatory effect on the back skin tissue of mice. Masson staining shows that TBE has a repair effect on mice dorsal skin tissue. In addition, the inflammatory factors (IL-1β, IL-6, TNF-α) in the mice dorsal skin tissues are significantly reduced but collagen (COL-1) is significantly increased. By cellular immunofluorescence assay, TBE is shown to promote PPAR-α expression in cells. Transcriptomics, metabolomics, and network pharmacology have revealed that TBE can regulate exogenous stimuli and cancer-related signaling pathways to prevent skin aging.

CONCLUSION

The results suggest that TBE can be a beneficial supplement to natural anti-aging.

Extraction and characterization of polysaccharide from fermented mycelia of Coriolus versicolor and its efficacy for treating nonalcoholic fatty liver disease

Coriolus versicolor, a popular traditional Chinese medicinal herb, is widely used in China to treat spleen and liver diseases; however, the beneficial effects of C. versicolor polysaccharides (CVPs) on nonalcoholic fatty liver disease (NAFLD) remain elusive. Herein we isolated and purified a novel CVP (molecular weight, 17,478 Da) from fermented mycelium powder. This CVP was composed of mannose, galacturonic acid, glucose, galactose, xylose, and fucose at a molar ratio of 22:1:8:15:10:3. Methylation, gas chromatography-mass spectrometry, and nuclear magnetic resonance analyses indicated that the CVP backbone consisted of →1)-β-D-Man-(6,4→1)-α-D-Gal-(3→1)-α-D-Man-(4→1)-α-D-Gal-(6→, with branches of →1)-α-D-Glc-(6→1)-α-D-Man-(4,3→1)-β-D-Xyl-(2→1)-β-D-Glc on the O-6 position of →1)-β-D-Man-(6,4→ of the main chain. The secondary branches linked to the O-4 position of →1)-α-D-Man-(4,3→ with the chain of →1)-α-D-Fuc-(4→1)-α-D-Man. Further, CVP treatment alleviated the symptoms of NAFLD in an HFD-induced mice model. CVP altered gut microbiota, predominantly suppressing microbes associated with bile acids both in the serum and cecal contents. In vitro data showed that CVP reduced HFD-induced hyperlipidemia via farnesoid X receptor. Our results improve our understanding of the mechanisms underlying the cholesterol- and lipid-lowering effects of CVP and indicate that CVP is a promising candidate for NAFLD therapy.

Determining the potent immunostimulation potential arising from the heteropolysaccharide structure of a novel fucoidan, derived from Sargassum Zhangii

A preliminary study was conducted of the chemical, structural properties and immunomodulatory activities of fucoidan isolated from Sargassum Zhangii (SZ). Sargassum Zhangii fucoidan (SZF) was determined to have a sulfate content of 19.74 ± 0.01% (w/w) and an average molecular weight of 111.28 kDa. SZF possessed a backbone structure of (1,4)-α-d-linked-galactose, (3,4)-α-l-fucose, (1,3)-α-d-linked-xylose, β-d-linked-mannose and a terminal (1,4)-α-d-linked-glucose. The main monosaccharide composition was determined as (w/w) 36.10% galactose, 20.13% fucose, 8.86% xylose, 7.36% glucose, 5.62% mannose, and 18.07% uronic acids, respectively. An immunostimulatory assay showed that SZF, compared to commercial fucoidans (Undaria pitnnaifida and Fucus vesiculosus sources), significantly elevated nitric oxide production via up-regulation of cyclooxygenase-2 and inducible nitric oxide synthase at both gene and protein levels. These results suggest that SZ has the potential to be a source of fucoidan with enhanced properties that may act as a useful ingredient for functional foods, nutritional supplements, and immune enhancers.

Medicinal Plants in Peru as a Source of Immunomodulatory Drugs Potentially Useful Against COVID-19

The current COVID-19 pandemic, characterized by a highly contagious severe acute respiratory syndrome, led us to look for medicinal plants as an alternative to obtain new drugs, especially those with immunomodulatory abilities, capable of acting against the pulmonary infection caused by coronavirus 2 (SARS-CoV-2). Despite medical advances with COVID-19 drugs and vaccines, plant-based compounds could provide an array of suitable candidates to test against this virus, or at the very least, to alleviate some symptoms. Therefore, this review explores some plants widely used in Peru that show immunomodulatory properties or, even more, contain phytoconstituents potentially useful to prevent or alleviate the COVID-19 infection. More interestingly, the present review highlights relevant information from those plants to support the development of new drugs to boost the immune system. We used three criteria to choose nine vegetal species, and a descriptive search was then conducted from 1978 to 2021 on different databases, using keywords focused on the immune system that included information such as pharmacological properties, phytochemical, botanical, ethnobotanical uses, and some clinical trials. From these literature data, our results displayed considerable immunomodulation activity along with anti-inflammatory, antiviral, antioxidant, and antitumoral activities. Noticeably, these pharmacological activities are related with a wide variety of bioactive phytoconstituents (mixtures or isolated compounds) which may be beneficial in modulating the overt inflammatory response in severe COVID-19. Further scientific research on the pharmacological activities and clinical utilization of these potential plants are warranted.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s43450-023-00367-w.

Structural Characteristics, Antioxidant, and Immunostimulatory Activities of an Acidic Polysaccharide from Raspberry Pulp

The extraction and characterization of new bioactive plant-derived polysaccharides with the potential for use as functional foods and medicine have attracted much attention. In the present study, A novel acidic polysaccharide (RPP-3a) with a weight-average molecular weight (Mw) of 88,997 Da was isolated from the raspberry pulp. RPP-3a was composed of rhamnose, arabinose, galactose, glucose, mannose, and galacturonic acid at a molar ratio of 13.1:28.6:16.8:1.4:6.2:33.9. Structural analysis suggested that the RPP-3a backbone was composed of repeating units of →4)-β-Galp-(1→3,4)-α-Rhap-(1→[4)-α-GalAp-(1→4)-α-GalAp-(1→]_n with branches at the C-4 position of rhamnose. The side chain of RPP-3a, containing two branch levels, was comprised of α-Araf-(1→, →5)-α-Araf-(1→, →3,5)-α-Araf-(1→, →3)-β-Galp-(1→, →3,6)-β-Galp-(1→, →4)-β-Glcp-(1→, and →2,6)-α-Manp-1→ residues. RPP-3a exhibited moderate reducing power and strong hydroxyl and superoxide anion radical scavenging abilities. RPP-3a significantly promoted the viability of RAW264.7 macrophages by increasing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) at both the expression and transcriptional levels. In summary, the immunostimulatory and antioxidant activities make RPP-3a a viable candidate as a health-beneficial functional dietary supplement.

Techno-functional properties and immunomodulatory potential of exopolysaccharide from Lactiplantibacillus plantarum MM89 isolated from human breast milk

An exopolysaccharide, designated as MM89-EPS, was isolated from Lactiplantibacillus plantarum MM89. It was comprised of glucose and mannose molecules with an average molecular weight of 138 kDa. FTIR and NMR spectra showed that MM89-EPS had characteristic polysaccharide functional groups. MM89-EPS displayed excellent water solubility and capacities to retain water and oil due to its porous structure. MM89-EPS exhibited no significant cytotoxicity on RAW264.7 cells and showed strong immunomodulatory activity by increasing phagocytosis, acid phosphatase activity, and cytokine production in RAW264.7 cells. Furthermore, an in vivo study revealed that splenic indices, intestinal IgA levels, serum cytokine levels, and lymphocyte proliferation were increased in an MM89-EPS-treated cyclophosphamide-induced immunosuppressed mouse model. To summarize, our results indicate that MM89-EPS can efficiently enhance the immunostimulatory activity of immune cells and an immunosuppressed mouse model. Hence, MM89-EPS may be use as a potential source of immunomodulatory agent in various food products.

Isolation, Structural Characterization and Macrophage Activation Activity of an Acidic Polysaccharide from Raspberry Pulp

The discovery of safe and effective plant polysaccharides with immunomodulatory effects has become a research hotspot. Raspberry is an essential commercial fruit and is widely distributed, cultivated, and consumed worldwide. In the present study, a homogeneous acidic polysaccharide (RPP-2a), with a weight-average molecular weight (Mw) of 55582 Da, was isolated from the pulp of raspberries through DEAE-Sepharose Fast Flow and Sephadex G-200 chromatography. RPP-2a consisted of rhamnose, arabinose, galactose, glucose, xylose, galacturonic acid and glucuronic acid, with a molar ratio of 15.4:9.6:7.6:3.2:9.1:54.3:0.8. The results of Fourier transform infrared spectroscopy (FT-IR), gas chromatography-mass spectrometer (GC-MS), 1D-, and 2D-nuclear magnetic resonance (NMR) analyses suggested that the backbone of RPP-2a was primarily composed of →2)-α-L-Rhap-(1→, →2,4)-α-L-Rhap-(1→, →4)-α-D-GalAp-(1→, and →3,4)-α-D-Glcp-(1→ sugar moieties, with side chains of α-L-Araf-(1→, α-L-Arap-(1→, and β-D-Galp-(1→3)-β-D-Galp-(1→ residues linked to the O-4 band of rhamnose and O-3 band of glucose residues. Furthermore, RPP-2a exhibited significant macrophage activation activity by increasing the production of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), and the expression of inducible nitric oxide synthase (iNOS) and cytokines at the transcriptional level in RAW264.7 cells. Overall, the results indicate that RPP-2a can be utilized as a potential natural immune-enhancing agent.

Protective Effects of Natural Polysaccharides on Intestinal Barrier Injury: A Review

Owing to their minimal side effects and effective protection from oxidative stress, inflammation, and malignant growth, natural polysaccharides (NPs) are a potential adjuvant therapy for several diseases caused by intestinal barrier injury (IBI). More studies are accumulating on the protective effects of NPs with respect to IBI, but the underlying mechanisms remain unclear. Thus, this review aims to represent current studies that investigate the protective effects of NPs on IBI by directly maintaining intestinal epithelial barrier integrity (inhibiting oxidative stress, regulating inflammatory cytokine expression, and increasing tight junction protein expression) and indirectly regulating intestinal immunity and microbiota. Furthermore, the mechanisms underlying IBI development are briefly introduced, and the structure-activity relationships of polysaccharides with intestinal barrier protection effects are discussed. Potential developments and challenges associated with NPs exhibiting protective effects against IBI have also been highlighted to guide the application of NPs in the treatment of intestinal diseases caused by IBI.

Preparation and characterization of 2-deacetyl-3-O-sulfo-heparosan and its antitumor effects via the fibroblast growth factor receptor pathway

Heparosan, with a linear chain of disaccharide repeating units of → 4) β-D-glucuronic acid (GlcA) (1 → 4)-α-D-N-acetylglucosamine (GlcNAc) (1→, is a potential starting chemical for heparin synthesis. However, the chemoenzymatic synthesis of single-site sulfated heparosan and its antitumor activity have not been studied. In this study, 2-deacetyl-3-O-sulfo-heparosan (DSH) was prepared successively by the N-deacetylation chemical reaction and enzymatic modification of human 3-O-sulfotransferase-1 (3-OST-1). Structural characterization of DSH was shown the success of the sulfation with the sulfation degree of 0.87. High performance gel permeation chromatography (HPGPC) analysis revealed that DSH had only one symmetrical sharp peak with a molecular weight of 9.6334 × 10⁴ Da. Biological function studies showed that DSH could inhibit tumor cell (A549, HepG2 and HCT116) viability and induce the apoptosis of A549 cells. Further in vitro mechanistic studies showed that DSH may induce apoptosis via the JNK signaling pathway, and the upstream signal of this process may be fibroblast growth factor receptors. These results indicated that DSH could be developed as one of a potential chemical for tumor treatment.

Pectic polysaccharides from edible halophytes: Insight on extraction processes, structural characterizations and immunomodulatory potentials

The preparation, chemical properties and bio-activities of polysaccharides derived from halophytes have gained an increasing interest in the past few years. Phytochemical and pharmacological reports have shown that carbohydrates are important biologically active compounds of halophytes with numerous biological potentials. It is believed that the mechanisms involved in these bio-activities are due to the modulation of immune system. The main objective of this summary is to appraise available literature of a comparative study on the extraction, structural characterizations and biological potentials, particularly immunomodulatory effects, of carbohydrates isolated from halophytes (10 families). This review also attempts to discuss on bioactivities of polysaccharides related with their structure-activity relationship. Data indicated that the highest polysaccharides yield of around 35% was obtained under microwave irradiation. Structurally, results revealed that the most of extracted carbohydrates are pectic polysaccharides which mainly composed of arabinose (from 0.9 to 72%), accompanied by other monosaccharides (galactose, glucose, rhamnose, mannose and xylose), significant amounts of uronic acids (from 18.9 to 90.1%) and some proportions of fucose (from 0.2 to 8.3%). The molecular mass of these pectic polysaccharides was varied from 10 to 2650 kDa. Hence, the evaluation of these polysaccharides offers a great opportunity to discover novel therapeutic agents that presented especially beneficial immunomodulatory properties. Moreover, reports indicated that uronic acids, molecular weights, as well as the presence of sulfate and unmethylated acidic groups may play a significant role in biological activities of carbohydrates from halophyte species.

Dietary Astragalus polysaccharides ameliorates the growth performance, antioxidant capacity and immune responses in turbot (Scophthalmus maximus L.)

Supplying immunostimulants to aquatic feed has been an effective way to enhance the health of aquatic animals and substitute for antibiotics. In the present study, the potential effects of Astragalus polysaccharides (APS) were evaluated in turbot, Scophthalmus maximus. Two levels of APS (50 and 150 mg/kg) were added to the basal diet (CON) and a 63-day growth trial (initial weight 10.13 ± 0.04 g) was conducted. As the results showed, significant improvement on growth performance in the APS groups were observed. In addition, dietary 150 mg/kg APS significantly increased the total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-PX) and lysozyme activities in liver. Meanwhile, APS diets induced the mRNA expression of toll-like receptors (TLRs) such as tlr5α, tlr5β, tlr8 and tlr21, while reduced the expression of tlr3 and tlr22. The expression of inflammatory genes myeloid differentiation factor 88 and nuclear factor kappa b p65 and pro-inflammatory cytokines tumor necrosis factor-α and interleukin-1β were up-regulated in APS groups while the expression of anti-inflammatory cytokine transforming growth factor beta was inhibited. Taken together, the present study indicated that Astragalus polysaccharides could remarkably enhance the growth performance, antioxidant activity and maintain an active immune response in turbot.

Characterization of guava (Psidium guajava Linn) seed polysaccharides with an immunomodulatory activity

To clarify the property of a novel guava seed polysaccharide (GSPS), GSPS was subjected to purify using Sepharose 6B gel filtration chromatography and further characterize the property of each individual isolated fraction. GSPS further resolved into three purified fractions, guava seed polysaccharide fraction 1 (GSF1), GSF2 and GSF3. Isolated GSF1, GSF2 and GSF3 were respectively subjected to high performance size exclusion chromatography; molecular weights of three polysaccharide fractions were determined. GSPS, GSF1, GSF2 and GSF3 were suggested to be proteopolysaccharides or glycoproteins. GSPS, GSF1, GSF2 and GSF3, particularly GSF3, were found to have a Th2-inclination property and anti-inflammatory potential. Heated GSF3 did not significantly (P > .05) decreased its immunomodulatory activity, suggesting that GSF3 is a proteopolysaccharide. The deproteinated GSF3 markedly lost its immunomodulatory activity, suggesting that both protein and carbohydrate moiety in GSF3 are essential to its immunomodulatory function. Analyses of monosaccharides composition in GSF3 using a pre-column derivatization high performance liquid chromatography exhibited that GSF3 was composed of glucuronic acid (3.28%), galacturonic acid (28.13%), galactose (14.88%), mannose (3.96%), glucose (22.99%), arabinose (7.31%), ribose (1.55%), xylose (14.81%), fucose (1.68%) and rhamnose (1.43%). Overall, we evidence that GSF3 is a low molecular weight proteopolysaccharide with potent anti-inflammatory and immunomodulatory effects.

Extraction of polysaccharides from maca: Characterization and immunoregulatory effects on CD4+ T cells

The immunomodulatory effects of maca polysaccharides (MCPs) on macrophages have been demonstrated in many studies. However, the effects of MCPs on CD4⁺ T cells have not been studied. Four water-soluble MCPs, labeled MCP1 (weight-average molecular weights [Mws] of 896.1 and 276.6 kDa), MCP2 (Mws of 337.8 and 219.0 kDa), MCP3 (Mws of 110.6, 58.1, and 38.9 kDa), and MCP4 (Mws of 15.7, 12.6, and 12.1 kDa), were obtained from maca by graded ethanol precipitation. The immunoregulatory effects of MCPs on CD4⁺ T cells were evaluated for the first time. The experimental results indicated that all MCPs had immunoregulatory effects on CD4⁺ T cells. However, the effects of MCP2 were stronger compared to the other three components, not only in promoting the proliferation of CD4⁺ T cells but also in terms of secretion of interferon-γ (IFN-γ). The molecular weight and monosaccharide compositions of MCPs were analyzed to explore the structure-activity relationship. The results suggested that the molecular weight and the galactosamine (GalN) of MCPs might be determining factors for its bioactivity. These findings suggest that the MCP2 isolated in our study have immune potentiation effects on CD4⁺ T cells.

A novel acidic polysaccharide from the residue of Panax notoginseng and its hepatoprotective effect on alcoholic liver damage in mice

This study presented the first purification and characterization of a hepatoprotective polysaccharide (PNPS-0.5 M) from the residue of Panax notoginseng (Burk.) F.H. Chen. This polysaccharide included a backbone of (4 → 1)-linked GalA and branches of (1→)-linked Araf, (1→)-linked Rhap, and (5 → 1)-linked Araf and had an extremely high molecular weight (2600 kDa). We investigated the hepatoprotective effects of PNPS-0.5 M on mice with alcoholic liver damage (ALD). After administration of PNPS-0.5 M, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), and hepatic malondialdehyde (MDA) were reduced to normal. In contrast, hepatic levels of alcohol dehydrogenase (ADH) and the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were elevated to normal. Further investigations indicated that PNPS-0.5 M activated Nrf2 signaling as a protective mechanism against Cyp2e1 toxicity in ALD mice. Meanwhile, it strengthened the ADH pathway and suppressed the CAT pathway of alcohol metabolism to prevent peroxide accumulation, thereby ameliorating ALD. In the present study, we describe a novel acidic polysaccharide from P. notoginseng with hepatoprotective activity that facilitates the development and utilization of P. notoginseng resources.

An orally administered butyrate-releasing xylan derivative reduces inflammation in dextran sulphate sodium-induced murine colitis

Butyrate has been shown to be effective in ulcerative colitis (UC). However, its oral administration is rare due to its rancid odour and unpleasant taste. In this study, the effect of a butyrate-releasing polysaccharide derivative, xylan butyrate ester (XylB), was evaluated in a dextran sodium sulphate (DSS)-induced UC model in C57BL/6 mice. Linear xylan was extracted from corn cobs. The C-2 and C-3 positions of the linear xylan were esterified with butyrate, forming XylB. The protective and therapeutic effects of XylB against UC were determined in a DSS-induced mouse model. The results showed that XylB treatments reversed the imbalance between pro- and anti-inflammatory cytokines. Moreover, XylB rebalanced the gut microbiota that interfered with DSS treatment and significantly decreased the relative abundance of the genera Oscillibacter, Ruminococcaceae UCG-009, Erysipelatoclostridium, and Defluviitaleaceae UCG-01. XylB increased butyrate content in the colon, upregulated G-protein coupled receptor 109A protein expression, inhibited histone deacetylase (HDAC) activity, and exerted anti-inflammatory activity through autophagy pathway activation and nuclear factor-κB (NF-κB) inhibition. XylB reduces inflammatory intestinal damage in mice, suggesting that it would be a potential drug for the treatment of UC and could be used to overcome the limitations of the oral administration of sodium butyrate.

The Dipterose of Black Soldier Fly (Hermetia illucens) Induces Innate Immune Response through Toll-Like Receptor Pathway in Mouse Macrophage RAW264.7 Cells

In our study, a novel bioactive polysaccharide was identified in the larvae of the black soldier fly (BSF) (Hermetia illucens) as a molecule that activates the mammalian innate immune response. We attempted to isolate this molecule, which was named dipterose-BSF, by gel-filtration and anion-exchange chromatography, followed by nitric oxide (NO) production in mouse RAW264.7 macrophage cells as a marker of immunomodulatory activity. Dipterose-BSF had an average molecular weight of 1.47 × 10⁵ and consisted of ten monosaccharides. Furthermore, in vitro assays demonstrated that dipterose-BSF enhanced the expression of proinflammatory cytokines and interferon β (IFNβ) in RAW264.7 cells. The inhibition of Toll-like receptor 2 (TLR2) and 4 (TLR4) significantly attenuated NO production by dipterose-BSF, indicating that dipterose-BSF stimulates the induction of various cytokines in macrophages via the TLR signaling pathway. This observation was analogous with the activation of nuclear factor kappa B in RAW264.7 cells after exposure to dipterose-BSF. Our results suggest that dipterose-BSF has immunomodulatory potential through activating the host innate immune system, which allows it to be a novel immunomodulator for implementation as a functional food supplement in poultry, livestock, and farmed fish.

Advances in Research on Immunoregulation of Macrophages by Plant Polysaccharides

Polysaccharides are among the most important members of the biopolymer family. They are natural macromolecules composed of monosaccharides. To date, more than 300 kinds of natural polysaccharide compounds have been identified. They are present in plants, animals, and microorganisms, and they engage in a variety of physiological functions. In the 1950s, due to the discovery of their immunoregulatory and anti-tumor activities, polysaccharides became a popular topic of research in pharmacology, especially in immunopharmacology. Plants are an important source of natural polysaccharides. Pharmacological and clinical studies have shown that plant polysaccharides have many functions, such as immune regulation, anti-tumor activity, anti-inflammatory activity, anti-viral functions, anti-radiation functions, and a hypoglycaemic effect. The immunomodulatory effects of plant polysaccharides have received much attention. Polysaccharides with these effects are also referred to as biological response modifiers (BRMs), and research on them is one of the most active areas of polysaccharide research. Thus, we summarize immunomodulatory effects of botanical polysaccharides isolated from different species of plants on the macrophage. The primary effect of botanical polysaccharides is to enhance and/or activate macrophage immune responses, including increasing reactive oxygen species (ROS) production, and enhancing secretion of cytokines and chemokines. Therefore, it is believed that botanical polysaccharides have significant therapeutic potential, and represent a new method for discovery and development of novel immunomodulatory medicine.

Purification, antitumor and anti-inflammation activities of an alkali-soluble and carboxymethyl polysaccharide CMP33 from Poria cocos

A carboxymethyl polysaccharide CMP33 (15.23 × 10⁴ Da) was isolated from edible and pharmaceutical mushroom Poria cocos using alkaline extraction followed by DEAE-52 and Saphadex-G200 + Saphadex-G150 column chromatographies. The structure analysis showed that CMP33 was composed of glucosyl residues containing a backbone chain of (1 → 3)-linked glucose residues and side chains of (1 → 6) and (1 → 2)-linked glucose residues, and possessed triple-helix structure. Bioassay results revealed that CMP33 displayed a dose-dependent inhibition on 5 cancer cells (HepG-2, MCF-7, SGC-7901, A549) in the range of 31.25-1000 μg/mL, but low cytotoxicity on normal liver cells L-O2. Moreover, CMP33 stimulated NO release and cytokine secretion (IL-1β, IL-6 and TNF-α), and also inhibited LPS-stimulated overproduction of NO, IL-6, TNF-α and IL-1β, in RAW264.7 cells. These results suggested that CMP33 possessed anticancer, anti-inflammation and immune-stimulation activities, and potential for developing as a bioactive ingredient in functional foods.

The impacts of natural polysaccharides on intestinal microbiota and immune responses – a review

This paper presents a comprehensive review of the impacts of natural polysaccharides on gut microbiota and immune responses as well as their interactions.

Optimization of Ultrasound-Assisted Extraction and Structural Characterization of the Polysaccharide from Pumpkin (Cucurbita moschata) Seeds

In the present study, ultrasound-assisted extraction (UAE) of crude polysaccharides (PSP) from pumpkin seeds was optimized by response surface method (RSM). The polysaccharide yield (2.29 ± 0.14%), which agreed closely with the theoretical predicted value 2.40%, was obtained under the optimal extraction conditions: extraction time 24 min, extraction temperature 50 °C, ultrasonic power 347 W, and liquid to solid ratio 23 mL/g. After further purification by two-step column chromatography, a novel polysaccharide (PSP-1) was isolated from pumpkin seeds. PSP-1 was composed of mannose, glucose, and galactose in a molar ratio of 1.00:4.26:5.78 with molecular weight of 3728 g/mol. 1D and 2D NMR spectroscopy analysis revealed that the backbone of PSP-1 was mainly formed by β→6)-β-d-Galp-(1→, →6)-α-d-Glcp-(1→, and →3,6)-β-d-Manp-(1→ with branching at O-3 and O-6 of →3,6)-β-d-Manp-(1→. Branch linkages were composed of α-d-Glcp-(1→ and →4)-α-d-Galp-(1→.