Chemical analysis and study of immunoenhancing and antioxidant property of a glucan isolated from an alkaline extract of a somatic hybrid mushroom of Pleurotus florida and Calocybe indica variety APK2

A water-soluble glucan isolated from an alkaline extract of fruit bodies of a somatic hybrid mushroom PCH9FB of Pleurotus florida and Calocybe indica var. APK2 strains showed antioxidant properties with immune activation of macrophage, splenocyte, and thymocyte. On the basis of acid hydrolysis, methylation, periodate oxidation and NMR studies ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) the structure of the repeating unit of the glucan was established as: [structure: see text].     

Structural characterization of an immunoenhancing cytotoxic heteroglycan isolated from an edible mushroom Calocybe indica var. APK2

A water-soluble polysaccharide of an edible mushroom Calocybe indica var. APK2 showed immunoenhancing (macrophage, splenocyte, thymocyte, and bone marrow activation) and cytotoxic activity toward HeLa cell lines and found to consist of d-glucose, d-galactose, and l-fucose in a molar ratio of nearly 3:1:1. On the basis of acid hydrolysis, methylation analysis, and NMR studies (¹H, ¹³C, DEPT-135, TOCSY, DQF–COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of the fuco-galacto-glucan was established as:     

Structural characterization and study of immunoenhancing properties of heteroglycan isolated from a somatic hybrid mushroom (PfloVv1aFB) of Pleurotus florida and Volvariella volvacea

A water soluble polysaccharide isolated from the hot aqueous extract of the fruit bodies of the somatic hybrid mushroom (PfloVv1aFB), raised through protoplast fusion between the strains of Pleurotus florida and Volvariella volvacea was found to consist of d-glucose, d-galactose, and d-mannose in a molar ratio of nearly 4:1:1 and showed macrophage, splenocyte, and thymocyte activation. On the basis of sugar analysis, methylation analysis, periodate oxidation, and NMR studies (¹H, ¹³C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC and HMBC), the structure of the repeating unit of the polysaccharide was established as:     

Structural investigation of a polysaccharide (Fr. II) isolated from the aqueous extract of an edible mushroom, Pleurotus sajor-caju

A water-soluble polysaccharide, (Fr. II) isolated from aqueous extract of an edible mushroom Pleurotus sajor-caju, was found to consist of D-glucose, D-galactose, and D-mannose in a molar proportion of 1:1:1. Compositional analysis, methylation analysis, periodate oxidation study, partial hydrolysis, and NMR experiments ((1)H, (13)C, 2D-COSY, TOCSY, NOESY, HSQC, and HMBC) revealed the presence of the following repeating unit in the polysaccharide: [formula: see text]     

The structure of a polysaccharide from Fraction-II of an edible mushroom, Pleurotus florida

A water-soluble polysaccharide was isolated from Fraction-II of the aqueous extract of the fruit bodies of the mushroom, Pleurotus florida. Compositional analysis, methylation analysis, periodate oxidation study, Smith degradation, and NMR studies (1H, 13C, DQF-COSY, TOCSY, NOESY, HSQC, and HMBC) revealed the presence of the following repeating unit in the polysaccharide: [structure: see text].     

Intergeneric protoplast fusion between Calocybe indica (milky mushroom) and Pleurotus florida aids in the qualitative and quantitative improvement of sporophore of the milky mushroom

This article primarily focuses on the production of somatic hybrid sporophores through PEG-mediated protoplast fusion between Calocybe indica var. APK2 and Pleurotus florida. To screen the hybrid strains a selection strategy was followed based on the differential tolerance of NaCl level by the two parental genera. Basidiocarps could be successfully generated from eight out of fourteen hybrid lines that were maintained in culture. Hybridity of the fusant lines was established on the basis of their colony morphology, mycelial growth rate and hyphal traits, while the fruit-body-generating lines were demarcated on the basis of nature of sporophores, isozyme and RAPD markers. The degree to which the hybrid population differed among themselves and from their parents was assessed by analysing each of these morphological variables by one-way analysis of variance (ANOVA). RAPD bands of the fusant lines were similar to either parental bands or were new non-parental bands, which classified them into the microgenome and macrogenome insertion types. A dendrogram created with the help of UPGMA method of clustering and Euclidean distance exhibited three major clusters, in which the Pleurotus–Calocybe hybrids showed intra-cluster variations. Notably, P. florida was genetically distant from the hybrid lines, while C. indica was phylogenetically the dominant parent. Significant increase in bio-efficiency and γ-linoleic acid content in these hybrid lines indicated quantitative as well as qualitative improvement of the newly developed somatic hybrids.     

Structural characterization of a polysaccharide and a beta-glucan isolated from the edible mushroom Flammulina velutipes

Two polysaccharides were isolated from the basidiomycete Flammulina velutipes, via successive hot extraction with water, 2% and 25% aq. KOH, and then submitted to freeze-drying. The precipitate formed by repeated freeze-thawing from the 2% aq. KOH extraction PK2 was analyzed by determination of its monosaccharide composition, as well as by methylation analyses using GC-MS, mono- ((13)C, (1)H NMR) and bidimensional ((1)H (obs.), (13)C HMQC) spectroscopy, and controlled Smith degradations. It was established to be a branched beta-glucan, with a main chain of (1-->3)-linked-Glcp residues, substituted at O-6 by single-unit beta-Glcp side chains. The precipitate formed by repeated freeze-thawing from the 25% KOH extraction PK25 contained Xyl, Man, and Glc and was heterogeneous by HSPEC and extraction with DMSO gave a soluble xylomannan (XM). It was homogeneous with a molar mass 30.8 x 10(4)g/mol (dn/dc=0.186). Using the above chemical analyses, it was a xylomannan with Man and Xyl in a 3:2 molar ratio. Its main chain consisted of (1-->3)-linked alpha-Manp units, mainly substituted at O-4 by beta-Xylp units or with some beta-Xylp-(1-->3)-beta-Xylp groups.     

Glucans from alkaline extract of a hybrid mushroom (backcross mating between PfloVv12 and Volvariella volvacea): structural characterization and study of immunoenhancing and antioxidant properties

Two different glucans (water-soluble PS-I, water-insoluble PS-II) were isolated from the alkaline extract of the fruit bodies of hybrid mushroom. PS-I was found to consist of only (1→6)-linked β-D-glucopyranose. PS-II was composed of terminal, (1→3,4)-linked, and (1→3)-linked β-D-glucopyranosyl moieties in a molar ratio of nearly 1:1:1. PS-I showed macrophages, splenocytes, and thymocytes activation as well as antioxidant property. On the basis of sugar analysis, methylation analysis, and NMR studies ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of these glucans were established as:     

A gel-forming beta-glucan isolated from the fruit bodies of the edible mushroom Pleurotus florida

Glucans of basidiomycetes are considered to be an important class of polysaccharides, as they can act as biological response modifiers. We now isolate a gel-forming, water-soluble beta-glucan, with a molecular mass of 1.2 x 10(6)g/mol (HPSEC), from the fruit bodies of the edible mushroom Pleurotus florida, via alkaline extraction, followed by fractionation by freeze-thawing. Structural assignments were carried out using mono- and bi-dimensional nuclear magnetic resonance spectroscopy, monosaccharide composition, methylation analyses, and a controlled Smith degradation. It was a branched beta-glucan, with a main chain of (1-->3)-linked-Glcp residues, substituted at O-6 by single-unit Glcp side chains, on average to every fourth residue of the backbone.     

Structural characterization and in vitro antitumor activity of a novel polysaccharide isolated from the fruiting bodies of Pleurotus ostreatus

A novel water-soluble polysaccharide (POPS-1) was obtained from the fruiting bodies of Pleurotus ostreatus by hot water extraction, ethanol precipitation, and fractionated by DEAE-cellulose ion exchange chromatography and sepharose CL-6B gel filtration chromatography using an ATKA explore 100 purifier. The structure characterization and antitumor activity of the POPS-1 were evaluated in this paper. According to GC analysis, HPGPC, FT-IR, partial acid hydrolysis, periodate oxidation and Smith degradation, methylation and GC-MS analysis, the results indicate POPS-1 (M(w)=31 kDa) was composed of Man; Gal; Glc with a molar ratio of 1:2.1:7.9, it had a backbone of beta-(1-->3)-linked glucose residues, which occasionally branches at O-6. The branches were composed of (1-->3)-linked Glc, (1-->4)-linked Gal, (1-->4)-linked Man, and terminated with Glc and Gal residues. Cytotoxicity assay showed POPS-1 presented significantly higher antitumor activity against Hela tumor cell in vitro, in a dose-dependent manner, and exhibited significantly lower cytotoxicity to human embryo kidney 293T cells than Hela tumor cells compared with 5-Fu. The results suggest POPS-1 may be considered as a potential candidate for developing a novel low toxicity antitumor agent.     

Structural investigation of a polysaccharide (Fr. I) isolated from the aqueous extract of an edible mushroom, Volvariella diplasia

A water-soluble polysaccharide, (Fr. I) isolated from the aqueous extract of an edible mushroom, Volvariella diplasia, is composed of D-glucose, D-mannose, and D-galactose in a molar ratio 3:1:1. Compositional analysis, methylation analysis, periodate oxidation study, Smith degradation, and NMR studies (1H, 13C, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) revealed the presence of the following repeating unit in the polysaccharide: [FORMULA: SEE TEXT].     

Production and characterization of somatic hybrids raised through protoplast fusion between edible mushroom strains Volvariella volvacea and Pleurotus florida

Twelve somatic hybrid lines were raised through polyethylene glycol-mediated intergeneric protoplast fusion between Volvariella volvacea and Pleurotus florida using a double selection method. Four hybrid lines belonging to two distinct colony morphology types could be maintained in culture. Basidiocarps could be generated from two hybrid lines, one of which showed resemblance to the P. florida parent while the other showed intermediate parental morphology. Hybridity of the fusant lines was established on the basis of colony morphology, mycelial growth rate, hyphal traits, fruit body morphology, isozyme and RAPD analysis. Four isozyme activities were analyzed to provide biochemical criteria for detection of polymorphism among the hybrids and their parents. Using 20 random decamers a total of 203 RAPD bands ranging from 0.09 to 1.6 kb were observed. The UPGMA method of clustering exhibited two major phylogenetic clusters, the first of which comprised of the parents, two fruit body generating hybrid lines and their subsequent fruit body derived lines, while the two non-fruit body generating hybrid lines formed the out group of the first major cluster. Screening of a Pleurotus type hybrid line having high biological efficiency and generation of a temperature tolerant Pleurotus type line through backcross mating between a non-fruit body generating somatic hybrid and V. volvacea parent are the key achievements of this fusion programme.     

Structural characterization and biological activities of a new polysaccharide isolated from Morchella Sextelata

Glycoconjugate Journal - Morchella is the famous medicinal fungi in the ascomycetes. In this study, a new water-soluble polysaccharide (MSP-3-1) with an average molecular weight of 2.35 × 107...     

Structure elucidation and antioxidant activity of a novel polysaccharide isolated from Boletus speciosus Forst

In this study, a novel heteropolysaccharide was isolated from the fruiting bodies of Boletus speciosus Forst through DEAE-cellulose column and Sephadex G-200 column. The Boletus speciosus Forst polysaccharide (BSFP-1) had a molecular weight of 1.33×10(4) Da and was mainly composed of l-Man and d-Gal which ratios were 2:1. Structural features of Boletus speciosus Forst polysaccharide (BSFP-1) were investigated by a combination of total hydrolysis, methylation analysis, gas chromatography-mass spectrometry (GC-MS), infrared (IR) spectra and nuclear magnetic resonance (NMR) spectroscopy. The results indicated that Boletus speciosus Forst polysaccharide (BSFP-1) had a backbone of (1→4)-α-l-mannopyranose residues which branches at O-6 based on the experimental results. The branches were mainly composed of one with →1)-α-d-galactopyranose residue. The antioxidant activity of BSFP-1 was evaluated with two biochemical methods, including 1,1-diphenyl-2-picrylhydrazyl (DPPH(-)) radical scavenging, scavenging activity of 2,2'-azino-bis(3-ethylbenzthiazoline-6-suphonic acid)diammonium (ABTS(+)) radical. The results indicated that BSFP-1 showed strong antioxidant.     

Molecular characterization of a novel peroxidase isolated from the ligninolytic fungus Pleurotus eryngii

A haem peroxidase different from other microbial, plant and animal peroxidases is described. The enzyme is secreted as two isoforms by dikaryotic Pleurotus eryngii in peptone-containing liquid medium. The corresponding gene, which presents 15 introns and encodes a 361-amino-acid protein with a 30-amino-acid signal peptide, was isolated as two alleles corresponding to the two isoforms. The alleles differ in three amino acid residues and in a seven nucleotide deletion affecting a single metal response element in the promoter. When compared with Phanerochaete chrysosporium peroxidases, the new enzyme appears closer to lignin peroxidase (LiP) than to Mn-dependent peroxidase (MnP) isoenzymes (58–60% and 55% identity respectively). The molecular model built using crystal structures of three fungal peroxidases as templates, also showed high structural affinity with LiP (C_α-distance 1.2 Å). However, this peroxidase includes a Mn²⁺ binding site formed by three acidic residues (E36, E40 and D175) near the haem internal propionate, which accounts for the ability to oxidize Mn²⁺. Its capability to oxidize aromatic substrates could involve interactions with aromatic residues at the edge of the haem channel. Another possibility is long-range electron transfer, e.g. from W164, which occupies the same position of LiP W171 recently reported as involved in the catalytic cycle of LiP.     

Isolation and characterization of an immunoenhancing glucan from alkaline extract of an edible mushroom, Lentinus squarrosulus (Mont.) Singer

A water-soluble glucan, isolated from the alkaline extract of the fruit bodies of an edible mushroom, Lentinus squarrosulus (Mont.) Singer was found to consist of (1→3,6)-linked, (1→3)-linked, (1→6)-linked, and terminal β-d-glucopyranosyl moieties in a relative proportion of approximately 1:2:1:1. This polysaccharide showed optimum activation of macrophages as well as splenocytes and thymocytes at 10 μg/mL. Structural investigation was carried out using sugar analysis, methylation analysis, periodate oxidation study, and NMR experiments (¹H, ¹³C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC). On the basis of above-mentioned experiments, the structure of the repeating unit of the polysaccharide was established as: