Chemical analysis of a new (1→3)-, (1→6)-branched glucan from an edible mushroom, Pleurotus florida

Research progress and future development potential of Flammulina velutipes polysaccharides in the preparation process, structure analysis, biology, and pharmacology: A review

In recent years, Flammulina velutipes (F. velutipes) has attracted consequential attention in various research fields due to its rich composition of proteins, vitamins, amino acids, polysaccharides, and polyphenols. F. velutipes polysaccharides (FVPs) are considered as key bioactive components of F. velutipes, demonstrating multiple physiological activities, including immunomodulatory, anti-inflammatory, and antibacterial properties. Moreover, they offer health benefits such as antioxidant and anti-aging properties, which have exceptionally valuable clinical applications. Polysaccharides derived from different sources exhibit a wide range of biomedical functions and distinct biological activities. The varied biological functions of polysaccharides, coupled with their extensive application in functional foods and clinical applications, have prompted a heightened focus on polysaccharide research. Additionally, the extraction, deproteinization, and purification of FVPs are fundamental to investigate the structure and biological activities of polysaccharides. Therefore, this review provides a comprehensive and systematic overview of the extraction, deproteinization, purification, characterization, and structural elucidation of FVPs. Furthermore, the biological activities and mechanisms of FVPs have been further explored through in vivo and in vitro experiments. This review aims to provide a theoretical foundation and guide future research and development of FVPs.

Recent advances in the biosynthesis of fungal glucan structural diversity

Glucans are the most abundant class of macromolecule polymers in fungi, which are commonly found in Ascomycota and Basidiomycota. Fungal glucans are not only essential for cell integrity and function but also crucial for the immense industrial interest in high value applications. They present a variety of structural characteristics at the nanoscale due to the high regulation of genes and the involvement of stochastic processes in synthesis. However, although recent findings have demonstrated the genes of glucans synthesis are relatively conserved across diverse fungi, the formation and organization of diverse glucan structures is still unclear in fungi. Here, we summarize the structural features of fungal glucans and the recent developments in the mechanisms of glucans biosynthesis. Furthermore, we propose the engineering strategies of targeted glucan synthesis and point out the remaining challenges in the synthetic process. Understanding the synthesis process of diverse glucans is necessary for tailoring high value glucan towards specific applications. This engineering strategy contributes to enable the sustainable and efficient production of glucan diversity.

Preparation, structural characterization, and bioactivities of polysaccharides from Psidium guajava: A review

Psidium guajava L. is one of the most pivotal members belong to the Myrtaceae family, and it is an important tropical fruit with highly nutritional, healthy, and pharmacological values prevailing in worldwide for decades. The polysaccharides of P. guajava (PGPs) are served as one of the most active constituents, which possess a variety of biofunctionalities including anti-inflammatory, antidiarrheic, antihypertension, and antidiabetic properties. Hence, a systematic review aimed to comprehensively summarize the recent research advances of PGPs is necessary for facilitating their better understanding. The present review discussed current research progress on the PGPs, including extraction and purification methods, structural features, biological activities, and potential pharmacological mechanism. In addition, this review may also provide some valuable insights for further development and potential value in affording functionally useful agents in food industry or therapeutically effective medicine in the fields of P. guajava polysaccharides.

Extraction, characterization and anti-oxidant activity of polysaccharide from red Panax ginseng and Ophiopogon japonicus waste

Red ginseng and Ophiopogon japonicus are both traditional Chinese medicines. They have also been used as food in China for thousands of years. These two herbs were frequently used in many traditional Chinese patent medicines. However, the carbohydrate compositions of these two herbs were not normally used during the production of said medicine, such as Shenmai injection, resulting in a large amount of waste composed of carbohydrates. In this study, the extraction conditions were optimized by response surface methodology. The Shenmai injection waste polysaccharide was extracted by using distilled water that was boiled under the optimized conditions. The Shenmai injection waste polysaccharide (SMP) was thereby obtained. SMP was further purified by anion exchange chromatography and gel filtration. With this method, a neutral polysaccharide fraction (SMP-NP) and an acidic polysaccharide fraction (SMP-AP) were obtained. The results of structure elucidation indicated that SMP-NP was a type of levan, and SMP-AP was a typical acidic polysaccharide. SMP-NP exhibited potential stimulation activity on the proliferation of five different Lactobacilli strains. Therefore, SMP-AP could promote the antioxidant defense of IPEC-J2 cells. These findings suggest that Shenmai injection waste could be used as a resource for prebiotics and antioxidants.

Structural characteristic of polysaccharide isolated from Nostoc commune, and their potential as radical scavenging and antidiabetic activities

In this paper, Nostoc commune crude polysaccharide was extracted by heating and Ultrasonic-assisted methods separately, homogeneous polysaccharide HNCP3 and UNCP4 were obtained after purified by DEAE-52 cellulose column chromatography and Sephacryl G-100 gel column chromatography. The structures of HNCP3 and UNCP4 were characterized by molecular weight determination, infrared spectroscopy, DSC detection, sodium periodate oxidation, smith degradation reaction and methylation analysis. The conformation of the solution was studied by SEM and AFM. The results showed that the Ultrasonic-assisted extraction had effects on the molecular weight, monosaccharide composition, molar ratio and configuration of Nostoc commune. The main chain of HNCP3 and UNCP4 was → 6)-D-Glcp(1→ and → 2, 6)-D-Glcp, but UNCP4 contained 1, 2, 6-galactose and 2, 3-Me2-D-Ara branches, while HNCP3 did not. The results of the monosaccharides composition of indicated that mannose was presented in both HNCP3 and UNCP4. SEM and AFM showed that the structure of UNCP4 was helical, and the solution conformations of HNCP3 and UNCP4 were different in different solution environments. Studies on DPPH radicals, superoxide anions, and hydroxyl radicals scavenging abilities showed that UNCP4 had higher antioxidant activity, while studies on the antidiabetic activities showed that the hypoglycemic effect of UNCP4 was stronger than that of HNCP3. Therefore, Ultrasonic-assisted extraction (UAE) increases the bioactivity of Nostoc commune polysaccharide (NCP) as well as the extraction rate.

Structural characterization, antioxidant activity and anti-inflammatory of the phosphorylated polysaccharide from Pholiota nameko

In this study, a novel polysaccharide (SPN) was extracted by high-temperature pressure method and purified by a DEAE-52 column and a Sephadx G-100 gel column. PPN was obtained after phosphorylation of SPN. The differences of structural features, antioxidant activity, and anti-inflammatory effect of the two polysaccharides were investigated by chemical methods and RAW 264.7 cell model. SPN (Mw = 15.8 kDa) and PPN (Mw = 27.7 kDa) are an acidic polysaccharide with β-pyranose configuration, mainly containing rhamnose, mannose, glucose, arabinose, and galacose. FI-IR, NMR, and SEM spectra showed phosphorylation of SPN changed its structure. In methylation analysis, the major chains of SPN and PPN were 1,4-linked Glcp, 1,6-linked Galp, 1,2-linked Rhap, and 1.6-linked Manp with terminals of t-linked Glcp, t-linked Araf. The side chain of SPN was 1,4,6-linked Galp, 1,2,5-linked Araf, while the side chain of PPN was 1,4,6-linked Galp, 1,2,4-linked Glcp. In antioxidant activity experiments, the free radical scavenging rate of PPN was stronger than that of SPN. Also, PPN always has better anti-inflammatory on RAW 264.7 cells induced by LPS than that of SPN in same concentration, and it plays an anti-inflammatory role by inhibiting PI3K/AKT/mTOR pathway. The results indicated polysaccharide could significantly improve its antioxidant and anti-inflammatory function after phosphorylation. This study provides a potentially antioxidant and anti-inflammatory health food and drug.

Isolation, Purification, Characterization, and Immunomodulatory Activity Analysis of α-Glucans from Spirulina platensis

Crude polysaccharides from Spirulina platensis (SP) were isolated by maceration with a hot alkali solution and further fractionated by DEAE-52 cellulose and Sephadex G-100 chromatography into two purified fractions PSP-1 and PSP-2. The monosaccharide composition analysis indicated that SP was mainly composed of rhamnose and glucose, while PSP-1 and PSP-2 were composed only of glucose. The composition analysis of PSP-1 and PSP-2 by HPLC, FT-IR, and NMR showed that PSP-1 and PSP-2 were branching dextran, and their structures were (1 → 4)-linked-α-D-Glcp as the main chain, and C-6 replaced the single α-D-Glcp as the linear structure of the branch chain. The glucans (SP/PSP-1/PSP-2) can significantly improve the phagocytic ability of macrophages, enhance iNOS activity, promote NO production, and increase IL-6 mRNA expression, so they may possess certain immunomodulatory activity.

The detection, purity and structural properties of partially soluble mushroom and cereal β-D-glucans: A solid-state NMR study

β-D-glucans are proposed to have many health benefits. It is therefore important to have methods which can distinguish these from other carbohydrates present in natural products, as well as giving glucan content and structural information. Correlations between features in the CP/MAS spectra of β-D-glucans and enzyme assay determined β-D-glucan content were generally found to be poor. The β-D-glucan in dry and hydrated forms of the mushroom Ganoderma lucidum was investigated in detail by spectral peak fitting to the anomeric carbon C1 region in CP/MAS NMR spectra. Hydrated samples gave spectra with enhanced resolution and suggested that a clear distinction between β-D-glucans and other carbohydrates could be possible in the anomeric carbon C1 region. Chemical shift values for a range of carbohydrate polymers, which can be found alongside β-D-glucans, as well as the values for various linkages are given. Contamination by other carbohydrates and buffer salts is discussed.

Structure and hypoglycemic activity of a novel exopolysaccharide of Cordyceps militaris

A novel neutral exopolysaccharide (EPS-III) was isolated from culture broth of Cordyceps militaris (C. militaris). The EPS-III was a homogeneous polysaccharide with M_w of 1.56 × 10³ kDa. The yield of EPS-III from culture broth was 123.2 ± 3.1 mg/L and the sugar content was 93.32 ± 0.87%. The backbone of EPS-III was mainly consisted of →4)-α-D-Galp-(1→, while →3, 6)-α-D-Manp-(1→, →4)-α-D-Manp-(1→, →3)-β-D-Galp-(1→ and →3)-α-D-Glcp-(1→ were distributed in the backbone or in the branch chains. The EPS-III had helix structure when dissolved in weak alkaline solution. It also had branched and intertwined form on the surface. The inhibition of α-glucosidase significantly increased as the increase of purity of exopolysaccharides. The EPS-III had effective inhibition on the α-glucosidase with dose-effect relationship. Besides, the results of hypoglycemic activity analysis in vivo indicated that EPS-III can alleviate weight loss, reduce plasma glucose concentration, improve glucose tolerance, protect immune organs and repair dyslipidemia to relieve diabetes in STZ-induced diabetic mice. The manuscript first studied the hypoglycemic activity of exopolysaccharide of by C. militaris, proving and promoting the application value of culture broth. The structure characterization of EPS-III laid experimental foundations on the exploration of structure-activity relationship.

A comparative study on the structures of Grifola frondosa polysaccharides obtained by different decolourization methods and their in vitro antioxidant activities

Decolourization of polysaccharides is one of the crucial procedures that affects their structure, which is closely related to their bioactivity. Here, Grifola frondosa polysaccharide (GFP) was decolourized with H2O2 and AB-8 macroporous resin. Then, two main fractions, named DGFP and SGFP, were obtained by purification with Sepharose CL-4B. The molecular weights of these two polysaccharides were determined to be 6.306 × 106 (±0.410%) Da and 1.174 × 107 (±0.299%) Da by HPSEC. Monosaccharide analysis indicated that DGFP was composed of glucose, mannose, and galactose (32.20 : 1.00 : 1.75), while SGFP consisted entirely of glucose. Despite a backbone →4)-α-Glcp-(1→ in two polysaccharides, reducing ends Rα →3)-α-Glcp and Rβ →4)-β-Glcp were observed in DGFP by 1D/2D NMR. The results suggested that decolourization with low concentrations of H2O2 might alter the structure of GFP and generate new reducing ends. In vitro antioxidant results implied that DGFP exhibited a higher ability to scavenge DPPH and hydroxyl radicals and reduced the over-generated ROS levels in a concentration-dependent manner. These results suggested that the antioxidant effects of GFP could be activated by decolourization with H2O2. Therefore, DGFP might be a more promising natural antioxidant than SGFP.

Recent progress in the research of yam mucilage polysaccharides: Isolation, structure and bioactivities

Yam (Dioscorea spp.), known as an edible and medicinal tuber crop in China, has been used historically for the treatment of diabetes, diarrhea, asthma, and other ailments in traditional Chinese medicine. Moreover, it has been consumed as starchy food for thousands of years in China. Modern phytochemistry and pharmacological experiments have been proved that non-starch polysaccharide is one of the main bioactive substances of yam. Many studies have been focused on the isolation and identification of polysaccharides and their bioactivities of Chinese yam. However, due to the difference in the variety of raw materials and the method of polysaccharides extracting, the structure and biological activity of the obtained polysaccharides also differ. It has been demonstrated that Chinese yam polysaccharide has various important biological activities, such as hypoglycemia, immunomodulatory, antioxidant, and antitumor activities. This paper is aimed at summarizing previous and current references of the isolation processes, structural features and bioactivities of yam polysaccharides. The review will serve as a useful reference material for further investigation and application of yam polysaccharides in functional foods and medicine fields.

Polysaccharides of mushroom Pleurotus spp.: New extraction techniques, biological activities and development of new technologies

The biodiversity of mushrooms Pleurotus spp. is impressive due to its complexity and diversity related to the composition of chemical structures such as polysaccharides, glycoproteins and secondary metabolites such as alkaloids, flavonoids and betalains. Recent studies of polysaccharides and their structural elucidation have helped to direct research and development of technologies related to pharmacological action, production of bioactive foods and application of new, more sophisticated extraction tools. The diversity of bioactivities related to these biopolymers, their mechanisms and routes of action are constant focus of researches. The elucidation of bioactivities has helped to formulate new vaccines and targeted drugs. In this context, in terms of polysaccharides and the diversity of mushrooms Pleurotus spp., this review seeks to revisit the genus, making an updated approach on the recent discoveries of polysaccharides, new extraction techniques and bioactivities, emphasising on their mechanisms and routes in order to update the reader on the recent technologies related to these polymers.

Structural studies of a water insoluble β-glucan from Pleurotus djamor and its cytotoxic effect against PA1, ovarian carcinoma cells

A water insoluble β-glucan (PS), with molecular mass ∼9.16 × 10⁴ Da was isolated from the 4% alkaline extract of an edible mushroom, Pleurotus djamor and found to consist of (1→3)-β-d-glucopyranosyl moiety. The structure of the PS was elucidated on the basis of total hydrolysis, methylation analysis, periodate oxidation, and NMR experiments (¹H, ¹³C, DQF-COSY, DEPT-135, and HSQC). The structure of the repeating unit of the polysaccharide was established as: →3)-β-d-Glcp-(1→. The water insoluble β-glucan showed cytotoxic effect against PA1 cells, where˜50% population was destroyed at 100 μg/mL concentration, and almost all cells at 250 μg/mL concentration. The wound healing assay showed significant anticarcinogenic effect against ovarian carcinoma PA1 cells after 48 h of treatment.

Identification of genes underlying the enhancement of immunity by a formula of lentinan, pachymaran and tremelia polysaccharides in immunosuppressive mice

The efficacy of polysaccharides is widespread, especially in immune regulation. However, the genetic basis of the changes in polysaccharides regulating immunity is unclear. To obtain genome-wide insights into transcriptome changes and regulatory networks, we designed a polysaccharide formula, comprising lentinan, pachymaran and tremelia, to increase the availability of their optimized active sites. In this case, we focused on a model of immunosuppression to investigate genes by digital gene expression (DGE) tag profiling in T and B cells. These genes were further validated by qRT-PCR and Western blot experiments. Consequently, polysaccharide formula treatment helped to recover the expression of immune-related genes, including CADM1, CCR2, IGLL1, LIGP1, and FCGR3, FCGR2 in B cells, as well as S100A8, S100A9, ChIL3, MMP8 and IFITM3 in T cells. These results suggest that treatment with polysaccharides improves the immunity of immunosuppressive mice by regulating genes associated with T and B cell functions.

Structural elucidation of a polysaccharide from Flammulina velutipes and its immunomodulation activities on mouse B lymphocytes

A novel polysaccharide FVPB2 was purified from fruiting bodies of Flammulina velutipes. Its structure was elucidated by monosaccharide composition and methylation analyses, UV-Visible and FTIR spectroscopy as well as NMR. FVPB2 was a homogeneous heteropolysaccharide (molecular weight ~ 1.50 × 104 Da) containing D-galactose, D-mannose, L-fucose, and D-glucose at molar ratio of 1.9:1.2:1:2.5. In vitro immunomodulatory studies showed FVPB2 induced proliferation of mouse spleen lymphocytes in a dose-dependent manner. The levels of IgM and IgG, secreted by B cells, increased after FVPB2 treatment. So FVPB2 has potential to be a new important immunomodulatory nutraceutical.

Studies on structure and antioxidant properties of a heteroglycan isolated from wild edible mushroom Lentinus sajor-caju

A water-soluble heteroglycan (PS-I) isolated from the aqueous extract of a wild edible mushroom Lentinus sajor-caju showed average molecular weight ∼1.79×10⁵Da. The structure of the polysaccharide was determined using chemical and 1D/2D NMR experiments. Acid hydrolysis indicated the presence of d-glucose, d-galactose, d-mannose, and l-fucose in a molar ratio of nearly 4:4:1:1 respectively. The presence of terminal Fucp, terminal Galp, (1→3)-Glcp, (1→6)-Galp, (1→6)-Glcp, (1→4,6)-Galp, and (1→2,4)-Manp moieties were established from methylation analysis. The chemical and NMR analyses indicated that the PS-I was a heteroglycan composed of a repeating unit with backbone chain of three (1→6)-α-d-galactopyranosyl residues, two (1→6)-β-d-glucopyranosyl residues, one (1→4)-α-d-mannopyranosyl residue, and two (1→3)-β-d-glucopyranosyl residues where one (1→6)-α-d-galactopyranosyl residue was branched at O-4 position with terminal α-l-fucopyranosyl residue and (1→4)-α-d-mannopyranosyl residue was branched at O-2 position with terminal α-d-galactopyranosyl residue and the structure was proposed as; The PS-I is a moderate antioxidant compound which showed DPPH radical scavenging activity, hydroxyl radical scavenging activity, ABTS radical scavenging property, reducing power, and ferrous ion chelating ability.

Nutraceutical, Anti-Inflammatory, and Immune Modulatory Effects of β-Glucan Isolated from Yeast

β-Glucan is a dietary fibre, found in many natural sources, and controls chronic metabolic diseases effectively. However, β-glucan from the yeast has rarely been investigated. Objectively, conditions were optimized to isolate β-glucan from the yeast (max. 66% yield); those optimized conditions included 1.0 M NaOH, pH 7.0, and 90°C. The purity and identity of the isolated β-glucan were characterized through FT-IR, SEM, DSC, and physicofunctional properties. The obtained results from DSC revealed highly stable β-glucan (m.p., 125°C) with antioxidant activity (TAC value 0.240 ± 0.0021 µg/mg, H₂O₂ scavenging 38%), which has promising bile acid binding 40.463% and glucose control (in vitro). In line with these results, we evaluated the in vivo anti-inflammatory potential, that is, myeloperoxidase activity and reduction in MDA and NO; protective effect on proteins and keeping viscosity within normal range exhibited improvement. Also, the in vivo cholesterol binding and reduction in the skin thickness by β-glucan were highly encouraging. Finally, our results confirmed that yeast β-glucan is effective against some of the inflammatory and oxidative stress markers studied in this investigation. In general, the effect of 4%  β-glucan was more noticeable versus 2%  β-glucan. Therefore, our results support the utilization of β-glucan as a novel, economically cheap, and functional food ingredient.

Physicochemical Characterization of Polysaccharides with Macrophage Immunomodulatory Activities Isolated from Red Ginseng (Panax ginseng C. A. Meyer)

In this study, four polysaccharide fractions designated as RGP1, RGP2, RGP3, and RGP4 were isolated from red ginseng by DEAE-52 cellulose chromatography, and their macrophage immunomodulatory activities were investigated. The results revealed that the proliferation, NO production, and neutral red phagocytosis of RAW 264.7 macrophage cells in groups treated with RGP1 and RGP2 in vitro were increased significantly compared to RGP3 and RGP4. In addition, the level of TNF-α in RAW 264.7 cells was significantly increased in RGP1 and RGP2 groups. All the results consistently indicated that polysaccharide fractions RGP1 and RGP2 had strong macrophage immunomodulatory activities. Furthermore, RGP1 and RGP2 were purified by Sephadex G-100 column and RGP2 was further fractionated into a homogeneous fraction RGP2-1, with the molecular weight of 2.16 × 104 Da. The analysis of monosaccharide composition revealed that RGP1 was composed of arabinose, glucose, and galactose with a relative molecular ratio of 0.02 : 0.88 : 0.10. RGP2-1 was composed of rhamnose, arabinose, glucose, and galactose with a relative molecular ratio of 0.02 : 0.10 : 0.77 : 0.11. These results provided evidences that the neutral polysaccharide fractions RGP1 and RGP2 possessed significant immunomodulatory activity and could be explored as a promising natural immunomodulating agent applied in functional foods or medicines.

Bioactivities, isolation and purification methods of polysaccharides from natural products: A review

Polysaccharides play multiple roles and have extensive bioactivities in life process and an immense potential in healthcare, food and cosmetic industries, due to their therapeutic effects and relatively low toxicity. This review describes their major functions involved in antitumor, anti-virus, and anti-inflammatory bioactivities. Due to their enormous structural heterogeneity, the approaches for isolation and purification of polysaccharides are distinct from that of the other macromolecules such as proteins, etc. Yet, to achieve the homogeneity is the initial step for studies of polysaccharide structure, pharmacology, and its structure-activity relationships. According to the experiences accumulated by our lab and the published literatures, this review also introduces the methods widely used in isolation and purification of polysaccharides.

Polyphenolic-polysaccharide conjugates of Sanguisorba officinalis L. with anticoagulant activity mediated mainly by heparin cofactor II

A macromolecular complex has been isolated from the dried flowering parts of medicinal plant Sanguisorba officinalis L. (So) by multi-step extraction procedure, including that with extraction by organic solvents to degrease the plant material, then with hot alkali, followed by neutralization, partitioning with organic solvents and dialysis. The complex was purified by size-exclusion chromatography into five fractions labeled as So1-So5. Individual fractions differed in the chemical composition and molecular weight distribution patterns. In vitro anticoagulant activity tests showed in all fractions more or less important inhibition of plasma clots, however, So3 and So4 were the most active. The anticoagulant activity of So3 was even more significant than that of the unfractionated complex So. These S. officinalis conjugates were able to inhibit mainly the activity of thrombin when they were mediated by heparin cofactor II, but what was unexpected they were the non-direct inhibitors of factor Xa, mediated by antitrombin, where such mechanism of action is typical for a highly sulphated glycosaminoglycans.

Differentiation of the seed coat and composition of the mucilage of Lepidium perfoliatum L.: a desert annual with typical myxospermy

Myxospermy is an important feature in seeds of many plant species grown in desert region. Fertilization can initiate differentiation of the seed coat epidermis into a specialized cell type with mucilage production. In the present study, comprehensive analyses were performed on the seed coat differentiation, mucilage production and composition, and seed germination in Lepidium perfoliatum (Brassicaceae), a desert annual with typical myxospermy in China. First, results indicated that mucilage was secreted uniformly at the outer tangential wall, resulting in compression of the cytoplasm to the bottom of the epidermal cells. Secondly, the inner tangential wall and two radial walls of the subepidermal cells were apparently thickened by production of a secondary cell wall material, which resulted in a 'typical' palisade appearance. Thirdly, immunohistochemical staining combined with the enzymatic digestion and infrared spectrum analysis of the mucilage indicated that, while one important component of the seed coat mucilage in L. perfoliatum was pectin, it also contained β-1,3-d-glucan and xyloglucan. Finally, seed germination showed that seeds with mucilage displayed significantly higher germination percentage than that of demucilaged seeds in abundant or excess water conditions. These results suggest that the possible ecological role of mucilage in L. perfoliatum is in the adaptation to habitats with well-watered and water-logged conditions, rather than water stress.

Water-soluble polysaccharides from Pleurotus ostreatus var. florida mycelial biomass

Pleurotus ostreatus var. florida known as Hiratake has a high nutritional value, presents medicinal and nutraceutical properties and it is one of the consumed mushrooms in Brazil. Thus, the aim of this study was to characterize the chemical structure of polysaccharides found in mycelial biomass produced by submerged culture of P. ostreatus var. florida in order to compare with those found in P. ostreatus var. florida fruit bodies. Aqueous and alkali extracts obtained from mycelial biomass were purified, 13C NMR, GC-MS and chemical techniques were used to characterize three polysaccharide structures: a mannogalactan (MG-PfM) with α-D-Galp and 3-O-Me-α-D-Galp units, both (1→6)-linked, highly substituted at O-2 by D-Manp, a glycogen-like polymer (GLY-PfM) with α-D-Glp (1→4)-linked main chain, partially substituted at O-6 by α-D-Glcp side chains and a (1→3), (1→6) β-D-glucan (βGLC-PfM) with a main chain of β-D-Glcp (1→3)-linked units, partially substituted at O-6 by side chains of 6-O-substituted β-D-glucopyranosyl units, on an average of one to every two residues of the backbone. These results show the possibility to obtain similar and also different molecules from those found in the fruiting body of the same mushroom species, therefore the submerged culture of mushroom is a promising way to give raise molecules of interest.

The physicochemical properties of a new class of anticancer fungal polysaccharides: a comparative study

The structural and physicochemical properties of polysaccharides isolated from fungi with anticancer properties were investigated. The majority of the polysaccharides considered, have the β-d-Glcp component mostly connected by 1→3 and 1→6 linkages in the backbones and the short branches, respectively. The established parameters of lead-like, drug-like and of known dug space (KDS) were used and the repeating units of the polysaccharides exhibit some overlap with these. It was found that a unique region of chemical space is occupied by the polysaccharides, with MW: 1.0 x 10(5) to 2.5 x 10(5) g mol(-1); LogP: -3.0 x 10(3) to -1.0 x 10(3); HD: 1.0 x 10(3) to 5.0 x 10(3); HA: 5.0 x 10(3) to 1.0 x 10(4); PSA: 5.0 x 10(4) to 1.0 x 10(5) and RB: 5.0 x 10(3) to 1.0 x 10(4). These findings can be exploited in antitumor drug discovery projects.

Characterization and lectin microarray of an immunomodulatory heteroglucan from Pleurotus ostreatus mycelia

Glucans isolated from various mushroom and mycelia sources are interestingly being studied nowadays as a potent therapeutic agent. The present work was focused on the isolation, characterization and immunomodulatory study of a novel water soluble glucan from the pure mycelia of Pleurotus ostreatus. The extracted glucan was found to have a high molecular weight of ∼2.7 × 10(6)Da and mainly comprised of glucose, mannose and fucose in a ratio of 3:2:1 with both β and α linkages. Presence of terminal or interior glucose, mannose and fucose residues was also revealed using a high throughput miniaturized platform of lectin microarray. The heteroglucan folded into a triple helical conformation and exhibited enhanced immune cell activation and anti-tumor potential in tumor bearing mice model. Thus, potential biological functions incorporated in these glucan molecules acts in accord with its structural property and exploration of such structure-function relationship will unveil its diverse mechanism of action.