Β-type Glycosidic Linkages Research Articles

Purification, structural identification, in vitro hypoglycemic activity and digestion characteristics of polysaccharides from the flesh and peel of wampee (Clausena lansium)

In this study, two polysaccharides were isolated from the flesh and peel of wampee, termed as PWP-F and PWP-P respectively, and their structural characteristics, in vitro antioxidant and hypoglycemic activities and digestion were investigated. Results indicated the molecular weight of PWP-F was higher than that of PWP-P and they were both mainly composed of galactose and arabinose. Both polysaccharides exhibited α-type and β-type glycosidic linkages based on FTIR analysis. NMR spectroscopy revealed that PWP-F mainly consisted of α-Araf-(1→, →3,5)-α-Araf-(1→, →2,5)-α-Araf-(1→, →4) → β-Galp-(1 → and α-GalpA-(1→, while PWP-P was composed of α-Araf-(1→, →3)-α-Araf-(1→, →5)-α-Araf-(1→, →3,6) → β-Galp-(1→ and α-GalpA-(1→. Scanning electron microscopy showed that PWP-P had more porous surface structure compared to PWP-F. Moreover, PWP-P exhibited superior antioxidant activity and significant inhibition of both α-glucosidase and α-amylase compared to PWP-F. Specifically, PWP-P demonstrated mixed inhibition against α-glucosidase and α-amylase. In vitro digestion results showed the molecular weight, polysaccharide and reducing sugar content of PWP-F and PWP-P decreased after simulative gastrointestinal digestion. Overall, PWP-P has great potential as a kind of new antioxidant and hypoglycemic agent.

Research on the Impact of Deep Eutectic Solvent and Hot-Water Extraction Methods on the Structure of Polygonatum sibiricum Polysaccharides.

Deep eutectic solvent (DES) and hot-water extraction (HWE) methods were utilized to extract polysaccharides from Polygonatum sibiricum, referred to as DPsP and WPsP, respectively. The extracted polysaccharides were purified using the Superdex-200 dextran gel purification system, resulting in three components for each type of polysaccharide. The structures of these components were characterized. The molecular weight analysis revealed that DPsP components had slightly larger molecular weights compared with WPsP, with DPsP-A showing a slightly higher dispersity index and broader molecular weight distribution. The main monosaccharide components of both DPsP and WPsP were mannose and glucose, while DPsP exhibited a slightly greater variety of sugar components compared with WPsP. FTIR analysis demonstrated characteristic polysaccharide absorption peaks in all six PSP components, with a predominance of acidic pyranose sugars. NMR analysis revealed the presence of pyranose sugars, including rhamnose and sugar aldehyde acids, in both DPsP-B and WPsP-A. DPsP-B primarily exhibited β-type glycosidic linkages, while WPsP-A predominantly displayed α-type glycosidic linkages, with a smaller fraction being β-type. These findings indicated differences in monosaccharide composition and structure between PSPs extracted using different methods. Overall, this study provided experimental evidence for future research on the structure-function relationship of PSPs.

Isolation, Characterization, and Compositional Analysis of Polysaccharides from Pinot Noir Wines: An Exploratory Study

It has been reported that polysaccharides in wine can interact with tannins and other wine components and modify the sensory properties of the wine. Unfortunately, the contribution of polysaccharides to wine quality is poorly understood, mainly due to their complicated structure and varied composition. In addition, the composition and molecular structure of polysaccharides in different wines can vary greatly. In this study, the polysaccharides were isolated from pinot noir wine, then separated into high-molecular-weight (PNWP-H) and low-molecular-weight (PNWP-L) fractions using membrane-based ultrafiltration. Each polysaccharide fraction was further studied using size exclusion chromatography, UV-Vis, FT-IR, matrix-assisted laser desorption/ionization-high-resolution mass spectrometry, and gas chromatography-mass spectrometry (GC-MS). The results showed that PNWP-L and PNWP-H had different chemical properties and compositions. The FT-IR analysis showed that PNWPs were acidic polysaccharides with α- and β-type glycosidic linkages. PNWP-L and PNWP-H had different α- and β-type glycosidic linkage structures. FT-IR showed stronger antisymmetric and symmetric stretching vibrations of carboxylate anions of uronic acids in PNWP-L, suggesting more uronic acid in PNWP-L. The size exclusion chromatography results showed that over 72% of the PNWP-H fraction had molecular sizes from 25 kDa to 670 kDa. Only a small percentage of smaller molecular polysaccharides was found in the PNWP-H fraction. In comparison, all of the polysaccharides in the PNWP-L fraction were below 25 KDa, with a majority distributed approximately 6 kDa (95.1%). GC-MS sugar composition analysis showed that PNWP-L was mainly composed of galacturonic acid, rhamnose, galactose, and arabinose, while PNWP-H was mainly composed of mannose, arabinose, and galactose. The molecular size distribution and sugar composition analysis suggested that the PNWP-L primarily consisted of rhamnogalacturonans and polysaccharides rich in arabinose and galactose (PRAG). In comparison, PNWP-H were mostly mannoproteins and polysaccharides rich in arabinose and galactose (PRAG). Further research is needed to understand the impacts of these fractions on wine organoleptic properties.

Lentinus edodes Polysaccharides Alleviate Acute Lung Injury by Inhibiting Oxidative Stress and Inflammation.

Acute lung injury (ALI) is a kind of lung disease with acute dyspnea, pulmonary inflammation, respiratory distress, and non-cardiogenic pulmonary edema, accompanied by the mid- and end-stage characteristics of COVID-19, clinically. It is imperative to find non-toxic natural substances on preventing ALI and its complications. The animal experiments demonstrated that Lentinus edodes polysaccharides (PLE) had a potential role in alleviating ALI by inhibiting oxidative stress and inflammation, which was manifested by reducing the levels of serum lung injury indicators (C3, hs-CRP, and GGT), reducing the levels of inflammatory factors (TNF-α, IL-1β, and IL-6), and increasing the activities of antioxidant enzymes (SOD and CAT) in the lung. Furthermore, PLE had the typical characteristics of pyran-type linked by β-type glycosidic linkages. The conclusions indicated that PLE could be used as functional foods and natural drugs in preventing ALI.

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.

Analysis of Acanthopanax giraldii Harms Polysaccharide II Composition and Its Immune-Protective Role in a Cyclophosphamide-Induced Immunosuppressive Mice Model

Acanthopanax giraldii Harms is commonly used in traditional Chinese medicine to treat rheumatism, improve joints, and strengthen muscles and bones. The polysaccharides present in A. giraldii Harms contain major bioactive substances, which have antioxidant, anticancer, and antiviral activities. In this study, the structural characterization of the homogeneous polysaccharide isolated from A. giraldii Harms, known as AHP-II, and its immunomodulatory effects in vivo will be studied. High-performance ion chromatography (HPIC) and high-performance gel permeation chromatography (HPGPC) based analyses revealed that AHP-II was composed of various monosaccharides, which included rhamnose, arabinose, galactose, glucose, mannose, galacturonic acid, and glucuronic acid in molar ratios of 29.5 : 24.6 : 23.8 : 4.4 : 5.7 : 8.8 : 3.1, respectively, and had a collective molecular weight of 80.21 × 103 Da. Fourier-transform infrared (FTIR) spectroscopy indicated the presence of a pyranose ring and β-type glycosidic linkages in AHP-II. In addition, immunomodulatory effect analyses of AHP-II that used a cyclophosphamide-induced immunosuppressive mouse model demonstrated that its treatment could significantly restore spleen and thymus indices, promote the proliferation of splenic lymphocytes, elevate CD4+ T lymphocyte percentage and CD4+ : CD8+ ratio in the spleen, promote macrophage phagocytosis, and restore cytokines (IL-6, TNF-α, IgM, and IgG) levels. These results suggested that AHP-II could potentially be used as natural immunomodulator and as an alternative treatment to reduce chemotherapy-induced immunosuppression.

Preparation of newly identified polysaccharide from Pleurotus eryngii and its anti-inflammation activities potential.

The anti-inflammatory effects of two newly identified Pleurotus eryngii polysaccharides (WPEP, NPEP) were determined in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages in this study. Characterization analysis revealed that molecular weights of WPEP and NPEP were 167and 274kDa, and were mainly composed of glucose with β-type glycosidic linkages. WPEP and NPEP could significantly inhibit LPS-induced inflammatory responses by regulating the production of NO, Protaglandin E2 (PGE2 ), Interleukin-1β (IL-1β), Tumor necrosis factor-α (TNF-α), and Interleukin-6 (IL-6). This was through the blocking of the activation of Mitogen-activated protein kinase (MAPK) pathway by inhibiting phosphorylation of p38, extracellular regulation of protein kinases 1/2, and stress-activated protein kinase/jun aminoterminal kinase. Moreover, WPEP and NPEP inhibited NF-κB signaling by reducing nuclear translocation and phosphorylation of p65. Overall, our results, for the first time identified two P. eryngii polysaccharides and demonstrated the related anti-inflammatory effects, which indicated the favorable potential of P. eryngii polysaccharide as specific functional foods. PRACTICAL APPLICATION: This study prepared and characterized newly identified Pleurotus eryngii water-soluble polysaccharide fractions and elucidated the nutritional benefits, mainly the immune response related to anti-inflammatory activities by utilizing lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Collectively, results of this study suggested that the P. eryngii polysaccharide fractions could be considered as potential candidates for exploration in the development of new immunomodulatory agent or functional supplementary foods.

The preparation of a cold-water soluble polysaccharide from Grifola frondosa and its inhibitory effects on MKN-45 cells.

In this study, a novel water soluble polysaccharide (named GFP-4) was extracted from Grifola frondosa at 4 oC, and its preliminary structure and inhibitory effects on human gastric carcinoma MKN-45 cells through the Fas/FasL death receptor apoptosis pathway were investigated. High-performance gel permeation chromatography (HPGPC), fourier-transform infrared spectroscopy (FT-IR), and ion chromatography (IC) results showed that GFP-4 was a 1.09 × 106 Da neutral hetero polysaccharide with pyranose rings, and α- and β-type glycosidic linkages that contained galactose, glucose, and mannose at a molar ratio of 1.00:3.45:1.19. MTT results indicated that GFP-4 significantly inhibited the proliferation of MKN-45 cells in a concentration-dependent manner. The H&E staining and Hoechst 33342/PI double staining results showed that GFP-4-treated MKN-45 cells were subjected to underwent typical apoptotic morphologic changes such as nuclear pyknosis, chromatin condensation, and an increase of membrane permeability. Annexin V-FITC/PI double staining, cell cycle analysis, and western blot results revealed the GFP-4 induced MKN-45 cells apoptosis through the Fas/FasL-mediated death receptor pathway with cells arrested at the G0/G1 phase. These data indicate that GFP-4 is a promising candidate for treating gastric cancer and provide a theoretical basis for the future development and utilization of G. frondosa clinically.

Isolation, characterization and antioxidant of polysaccharides from Stropharia rugosoannulata

In this study, polysaccharides from Stropharia rugosoannulata were isolated and purified by macroporous adsorption resin and ion exchange chromatography to produce SRP-1 and SRP-2. Preliminary structural characteristics of SRP-1 and SRP-2 were also investigated. Our results showed that SRP-1 was neutral, while SRP-2 was acidic polysaccharides. The molar ratios of monosaccharides in SRP-1 and SRP-2 were different, but glucose was the main monosaccharide. Both α-type and β-type glycosidic linkages were detected in SRP-1, whereas β-constitution was dominant in SRP-2. Both SRP-1 and SRP-2 had a (1 → 6)-α-D-glucan backbone. Furthermore, the antioxidant activities of polysaccharides against ABTS+, DPPH and OH– radicals were determined in vitro. The results indicated that SRP-2 had a stronger antioxidant capacity than that of SRP-1. Our results may be valuable with regard to the utilization of polysaccharides from S. rugosoannulata as potential pharmaceuticals.

Alcohol-soluble polysaccharide from Castanea mollissima blume: Preparation, characteristics and antitumor activity

Abstract CMBP was an alcohol-soluble polysaccharide extracted from Castanea mollissima blume. Our study aimed to investigate the preliminary structural characteristics and in vivo antitumor activity of CMBP. The contents of total sugar, protein and uronic acid in CMBP was 93.68%, 0.89% and 1.78%, respectively. GC and FTIR results suggested galactose and glucose were detected for CMBP (2.86 × 103 Da), while glucose was the dominant monosaccharide in CMBP and pyranose form and α- and β-type glycosidic linkages were founded for CMBP. Meanwhile, CMBP could exhibite strong antitumor effects on S180 tumor-bearing mice. The antitumor effects of CMBP were related to improving the immune response, which result from improving the levels of serum cytokines (TNF-α, IL-2 and IFN-γ), activating immune cells (macrophages, lymphocytes and NK cells), adjusting the distribution of lymphocyte subsets. The H&E staining and cell cycle results indicated CMBP could induce tumor cells apoptosis and extensive injuries.

An alcohol-soluble polysaccharide from Atractylodes macrocephala Koidz induces apoptosis of Eca-109 cells

In this study, polysaccharides from Atractylodes macrocephala Koidz (APA) which were soluble in alcohol were prepared, purified, analyzed the structure and investigated the antitumor activity in vitro cell experiment. Results of high-performance gel permeation chromatography (HPGPC), fourier-transform infrared spectroscopy (FT-IR), and gas chromatography (GC) showed that APA was a 2.1KDa neutral hetero polysaccharide composed of arabinose and glucose (molar ratio, 1.00:4.57) with pyranose rings and α-type and β-type glycosidic linkages. Results by MTT experiments showed that the proliferation inhibition was 74.63% in Eca109 cells treated with 2 mg/mL dose of APA. Annexin V/PI assay, Hoechst 33,258 staining, cell cycle distribution, rhodamine 123 dye assay and western blot assay clarified that APA could accelerate the apoptosis of Eca109 cells by mitochondrial pathway and stocked cells at S phase. These data indicated that APA is a promising potential candidate for therapeutic treatment of esophageal cancer.

Isolation, purification, and characterization of novel polysaccharides from lotus (Nelumbo nucifera) leaves and their immunostimulatory effects.

In this study, a crude water-soluble polysaccharide (LLWP-C) was extracted from lotus leaves and further purified by size exclusion chromatography, to obtain the two main polysaccharides, LLWP-1 and LLWP-3. Physical and chemical analyses showed that they were homogeneous polysaccharides in β-type glycosidic linkage. LLWP-1 was devoid of helical conformation, had a molecular weight of 85.1 kDa and was mainly composed of Rha, Ara, Gal, Glu, and GalA in a molar ratio of 7.0:24.8:28.0:6.0:26.4. LLWP-3 showed a helical conformation, had a molecular weight of 12.5 kDa and consisted mainly of Rha, Ara, Gal, Glu, Man, and GalA in a molar ratio of 6.6:9.8:15.0:8.9:6.1:47.2. It was demonstrated that LLWP-C and both purified LLWP-1 and LLWP-3 could effectively enhance the proliferation, phagocytosis, nitric oxide (NO), and cytokine secretions by activating corresponding mRNA expression in macrophages, via MAPK and NF-κB pathways. LLWP-3 displayed the greatest immunostimulatory potential, followed by LLWP-1 and LLWP-C. These findings suggest that polysaccharides extracted from lotus leaf exert immunostimulatory activity that could be further investigated to develop functional foods and natural immunopotentiating therapeutic agents.

Structural and functional analyses of three purified polysaccharides isolated from Chinese Huaishan-yams

The extraction, purification and structural of Chinese Huaishan-yams polysaccharides and their function were investigated in this study. Three water-soluble polysaccharides, designated as CYZ, CYS-1, CYS-2, were purified and the molecular weight were found to be 22 KDa, 41 KDa and 23 KDa, respectively. The HPLC results showed that they were composed of different monosaccharides and the content of monosaccharides varied significantly. 1H NMR and 13C NMR spectra showed that CYS-1 contained two α-type and four β-type glycosidic linkages and backbone of CYS-1 has two types of linkages, β-1 → 2 and β-1 → 4. CYS-2 contained two α type and three β-type glycosidic linkages, and the backbone has three types of linkages, β-1 → 2, β-1 → 4, and β-1 → 6. The antioxidant activities increased in the order of CYS-1 < CYZ < CYS-2 < crude polysaccharide. Further, crude polysaccharide CYS-1 (≥80 μg/mL) had a good ability of inhibiting α-glucosidase and significant inhibition on the relative proliferation rate of B16 murine melanoma cells middle dose (≥200 μg/mL).

Water Soluble Antioxidative Crude Polysaccharide From Russula senecis Elicits TLR Modulated NF-κB Signaling Pathway and Pro-inflammatory Response in Murine Macrophages.

Russula senecis has recently been reported as a new addition to macrofungal flora of West Bengal. Besides, it also emerged as a seasonal health promoting nutrient to local ethnic people and enlisted for the first time as tribal food in our previous publication. In this context, the present work was designed to establish such usefulness scientifically and to meet the aim, crude polysaccharide, Rusenan, was prepared using conventional heated water reflux. Initially, the polymers were characterized to determine chemical composition and for that spectrophotometry along with Fourier-transform infrared spectroscopy (FT-IR), high-performance thin-layer chromatography (HPTLC), and gas chromatography-mass spectrometry (GC-MS) were performed. Analysis indicated that Rusenan was consisted mainly of carbohydrate conjugated with trace amount of protein. Furthermore, glucose was detected as the major monosaccharide (mainly in β-type glycosidic linkage) while other monomers were presented in the order of galactose > mannose > xylose > rhamnose. Conversely, antioxidant potential was determined following eight in vitro systems where the fraction evidenced strong superoxide, hydroxyl, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, high affinity to Fe2+ as well as instant ability to donate electron with EC50 values ranging from 80 to 3885 μg/ml concentration. In addition, effect on murine macrophages was also investigated where the polysaccharide treatment increased cell proliferation, phagocytic activity, filopodia or lamellipodia formation, nitric oxide (NO) production and reactive oxygen species (ROS) synthesis. Thereafter, through reverse transcriptase polymerase chain reaction (RT-PCR) analysis, significant increase in the expression of Toll like receptor (TLR)-4, TLR-2 and nuclear factor kappa B (NF-κB) was observed; as a result alleviated level of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, IκB-α, and interferon (IFN)-γ were also noticed explaining definite immune-stimulatory activity of the fraction. Thus, overall finding suggests that R. senecis can be considered as a functional food and may be used in preparation of dietary supplement to enhance general health.

Purification, compositional analysis and antioxidant properties of polysaccharides from black ginseng

Purpose: To extract, purify black ginseng polysaccharides, and study their compositional analysis and antioxidant properties.Methods: Crude polysaccharides from black ginseng were prepared by hot water extraction and subjected to chromatographic purification on Sephadex G-75 and DEAE-cellulose and Sephadex G-75 columns to yield 4 polysaccharide components: BGP-60, BGP-65, BGP-70 and BGP-80. The BGPs were characterized by chemical analysis, gel permeation chromatography (GPC), gas chromatographymass spectrometry (GC-MS), and Fourier transform-infrared spectroscopy (FT-IR). Finally, the in vitro antioxidant activities of the BGPs were determined through their capacities to scavenge superoxide anion, as well as 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radicals.Results: The four fractions designated BGP-60, BGP-65, BGP-70 and BGP-80 were polysaccharides with glucose as the main component. They were acidic in nature, with estimated molecular weights (MWs) of 28.6, 26.7, 11.4 and 3.05 kDa, respectively. Fractions BGP-60, BGP-65 and BGP-80 had α- type glycosidic linkage, whereas BGP-70 had β-type glycosidic linkage. Compared with vitamin C (vit C), it was found that BGP-60, BGP-65, BGP-70 and BGP-80 had strong potential antioxidant activities; BGP-60 exhibited a stronger antioxidant activity than BGP-65, BGP-70 or BGP-80 against DPPH and superoxide anion radicals, while BGP-65 had the highest antioxidant activity against hydroxyl radical.Conclusion: These results suggest that BGPs may be beneficial in the development and manufacture as potential therapeutic agents and functional foods.Keywords: Black ginseng, Polysaccharides, Purification, Antioxidant activity, Functional foods

Purification, characterization and immunomodulatory activity of water extractable polysaccharides from the swollen culms of Zizania latifolia

The swollen culms of Zizania latifolia is a popular vegetable and traditional herbal medicine mainly consumed in some Asian countries. In our previous study, water extractable polysaccharide (ZLPs-W) and alkali extractable polysaccharide (ZLPs-A) was sequentially prepared from the swollen culms of Zizania latifolia. In vitro cell assay revealed that ZLPs-W without cytotoxicity had higher immunomodulatory activity than ZLPs-A. Therefore, in this study, ZLPs-W was further separated to three purified polysaccharides of ZLPs-W1, ZLPs-W2, and ZLPs-W3 by anion exchange chromatography and size exclusive chromatography in sequence. They were found to be homogeneous polysaccharides in β-type glycosidic linkage. ZLPs-W1 and ZLPs-W2 without triple helix conformation mainly contained Glc in molar percentage of 96.47% and 85.1%, respectively. ZLPs-W3 with triple helix conformation mainly consisted of Man, Rha, GalA, Glc, Gal and Ara in the molar ratio of 10.23:14.14:37.44:17.14:16.54:4.51. In addition, all the three purified polysaccharides could effectively enhanced the proliferation, phagocytosis, and nitric oxide production of murine macrophage RAW 264.7, suggesting that they possessed a potent immunostimulatory activity and could be developed as immunomodulator in medicine or functional food areas.

Introducing a novel mushroom from mycophagy community with emphasis on biomedical potency.

Mushrooms have been prized by humankind as medicine and culinary wonder since antiquity. Though several species are ethnically valued; many prospective species are still being discovered. One such wild macrofungus has recently been discovered during subsequent field surveys in West Bengal, India which in turn exposed as a traditionally consumed popular myco-food. The collected taxon was found to be unique with regard to its morphological as well as genetical features. After detailed characterizations, the fungus was identified as a novel taxon belonging to the genus Russula (Russulaceae, Basidiomycota). Besides, the investigation was further extended in search of new functional ingredients and in this context, a water soluble crude polysaccharide rich extract (Rusalan) was isolated from dried basidiocarps. Accumulating evidences from GC-MS, HPTLC, FT-IR along with several spectrophotometric methods postulated that the fraction consisted mainly of carbohydrate in triple helical conformation, where glucose was the major monosaccharide mostly with β-type glycosidic linkage. Conversely, Rusalan showed pronounced antioxidant activity in six in vitro assay systems with EC50 value ranging from 190–1328 μg/ml concentration. The crude polysaccharide was also evaluated against six bacterial strains using microdilution method and the growth of Staphylococcus aureus and Bacillus subtilis were found to be inhibited effectively. In addition, immune-stimulatory assays demonstrated that Rusalan could evidently promote proliferation, induce phagocytosis, release NO, produce intracellular ROS and upregulate mRNA expression of iNOS, TNF-α, COX-2, as well as IL-6 genes in in mouse macrophage cells. Therefore, aim of the present study was not only to describe a new taxon to the world mycoflora but also to introduce a potent therapeutic agent that could be explored for food and pharmaceutical purposes. However, isolation of active component and in vivo studies need to be designed further.

Characterization and bioactivities of a novel polysaccharide obtained from Gracilariopsis lemaneiformis.

Gracilariopsis lemaneiformis is a type of red alga that contains seaweed polysaccharide agar. In this study, a novel non-agar seaweed polysaccharide fraction named GCP (short of crude polysaccharide obtained from Gracilariopsis lemaneiformis) was isolated from Gracilariopsis lemaneiformis. Structural analysis showed that GCP shows triple helical chain conformation when dissolved in water and has many branches and long side chains. Also, 1→3 linkage is the major linkage and the sugar structures are galactopyranose configurations linked by β-type glycosidic linkages. Two macromolecular substance fractions (GCP-1 and GCP-2) were purified by DEAE Sepharose Fast Flow column chromatography. Moreover, a splenocyte damage assay and splenocyte proliferation assay were used to analyse the bioactivities of GCP, GCP-1 and GCP-2. It was demonstrated that polysaccharides could protect splenocyte damaged by H2O2; GCP-2 shows a greatest protection rate, that is, 92.8%, which significantly enhanced the splenocyte proliferation, and GCP showed the highest proliferation rate, 9.30%. The results suggested that this type of novel non-agar polysaccharide displayed remarkable antioxidant and immunomodulatory activities and early alkali treatment could decrease the activities. It may represent a potential material for health food and clinical medicines.

In vivo fermentation of a Pleurotus eryngii polysaccharide and its effects on fecal microbiota composition and immune response.

A novel, homogeneous Pleurotus eryngii polysaccharide (PEP) (molecular weight 426 kDa, purity 91.25 ± 3.14%) which mainly consisted of glucose with β-type glycosidic linkages was used to investigate in vivo fermentation behavior and effects on immune response in mice. Different doses (0.2, 0.4, 0.8 g per kg body weight) were orally administered to the mice for a period of six weeks. The results showed that the SCFA concentration, pH value, and moisture contents of cecum and colon contents were significantly altered with high-dose PEP treatment compared to the control group (P < 0.05). Moreover, the fecal microbiota in the PEP treated group was found to be structurally different compared to the control group; especially, the Porphyromonadaceae, Rikenellaceae, Bacteroidaceae and Lactobacillaceae abundances were all increased at the family level. In addition, the exerted immune response was significantly altered after the high-dose PEP oral administration. This exploratory study indicated that intake of PEP could have a positive role in gastrointestinal tract health.

Characterization, antioxidant activity and immunomodulatory activity of polysaccharides from the swollen culms of Zizania latifolia

The swollen culms of Zizania latifolia have been used as a vegetable and traditional herbal medicine in China, Japan, Korea and Southeast Asia countries. Up to date, there is little information about the polysaccharides from the swollen culms of Zizania latifolia and their potential bioactivities. In the present study, water extractable polysaccharide (ZLPs-W) and alkali extractable polysaccharide (ZLPs-A) was sequentially prepared from the swollen culms of Zizania latifolia. Both of ZLPs-W and ZLPs-A was found to be non-starch polydisperse heterpolysaccharide with β-type glycosidic linkage. ZLPs-W with triple helix conformation mainly composed of GalA, Glc and Gal. ZLPs-A without triple helix conformation mainly composed of Glc, Gal, Xyl and Ara. In in vitro antioxidant assay, ZLPs-W and ZLPs-A exhibited good scavenging activities. The EC50 of DPPH radical, superoxide radical and hydroxy radical scavenging activities for ZLPs-A is 1.87, 1.13 and 0.38mg/mL compared with that for ZLPs-W is 2.95, 3.99 and 0.5mg/mL, respectively. Moreover, in vitro cell assay revealed that ZLPs-W without cytotoxicity has higher immunomodulatory activity than ZLPs-A in terms of stimulation of phagocytic ability and NO production in murine macrophage RAW 264.7. At the treated concentration of 400μg/mL and 100μg/mL, ZLPs-W induced a highest phagocytosis index (1.76) and NO product (29.12μmol/L), respectively. The results suggest that polysaccharide from the swollen culms of Zizania latifolia could be explored as potential natural antioxidant and immunomodulatory agents in medicine or functional food fields.