Soumitra Mandal

Structural characterization of an immunoenhancing heteroglycan isolated from an aqueous extract of an edible mushroom, Lentinus squarrosulus (Mont.) Singer.

A water-soluble polysaccharide, isolated from the hot water extract of the fruiting bodies of an edible mushroom, Lentinus squarrosulus (Mont.) Singer was found to contain d-galactose, l-fucose, and d-glucose in a molar ratio of nearly 1:1:5. Structural investigation of the polysaccharide was carried out using acid hydrolysis, methylation analysis, periodate oxidation study, and NMR experiments ((1)H, (13)C, 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: This polysaccharide showed macrophage as well as splenocyte and thymocyte activation.

Isolation and characterization of the immunostimulating β-glucans of an edible mushroom Termitomyces robustus var.

Two immunostimulating β-glucans, PS-I (water soluble) and PS-II (water insoluble) isolated from hot water extract of the fruiting bodies of an edible mushroom Termitomyces robustus var. showed significant macrophage, splenocyte, and thymocyte activation. On the basis of total hydrolysis, methylation analysis, periodate oxidation, and NMR experiments ((1)H, (13)C, DQF-COSY, TOCSY, DEPT-135, HSQC, and HMBC), the structure of the repeating unit of the polysaccharides is established as: PS-I: ->6)β-D-Glcp-(1→ (Water-soluble glucan) PS-II: →3)-β-D-Glcp-(1→3)-β-D-Glcp-(1→ 6↑1 β-D-Glcp (Water-insoluble glucan, Termitan).

A heteroglycan from the mycelia of Pleurotus ostreatus: structure determination and study of antioxidant properties

A heteroglycan (PS) isolated from the mycelia of Pleurotus ostreatus was found to consist of l-fucose, d-mannose, and d-glucose in a molar ratio of nearly 1:2:3. On the basis of acid hydrolysis, methylation analysis, periodate oxidation, and NMR studies (1H, 13C, TOCSY, DQF-COSY, NOESY, ROESY, HSQC, HMBC, and DEPT), the structure of the repeating unit of the PS was determined. The repeating unit had a branched backbone composed of (1→6)-linked α and βd-glucose and (1→2)-linked α-l-fucose. Branching occurred at C-4 position of (1→6)-linked α-d-glucopyranosyl residue with terminal β-d-mannose and C-3 position of (1→6)-linked β-d-glucopyranosyl residue with (1→6)-α-d-mannopyranosyl moiety terminated by α-d-glucose. The structure of the repeating unit of the PS was proposed as: [formula: see text]. The antioxidant properties of the PS were studied. The scavenging activity of hydroxyl free radicals whose EC50 value of PS at 943 μg/mL was determined. Further, EC50 value of the PS at 53 μg/mL was observed for scavenging activity of superoxide free radicals. Chelating effects (54.82%) of ferrous ions were observed at 1mg/mL of the PS.

Chemical analysis of an immunoenhancing water-soluble polysaccharide of an edible mushroom, Pleurotus florida blue variant

An immunoenhancing polysaccharide isolated from the aqueous extract of the fruit bodies of the mushroom, Pleurotus florida blue variant, was found to consist of d-glucose and d-galactose in a molar ratio of nearly 5:1. On the basis of sugar analysis, methylation analysis, periodate oxidation, Smith degradation, 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 polysaccharide was established as: →6)-β-D-Glcp-(1→3)-α-D-glcp-(1→[6)-β-D-Glcp-(1]3→ α-D=Glcp. The molecule activated macrophages, splenocytes, and thymocytes.

A heteropolysaccharide from aqueous extract of an edible mushroom, Pleurotus ostreatus cultivar: structural and biological studies.

A water soluble polysaccharide isolated from the hot aqueous extract of Pleurotusostreatus cultivar was found to contain d-glucose and d-galactose in a molar ratio of nearly 7:1. Structural investigation was carried out using acid hydrolysis, methylation analysis, periodate oxidation, Smith degradation, and NMR studies ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC). On the basis of the above mentioned experiments the structure of the repeating unit of the polysaccharide was established as: This heteroglycan stimulates macrophages, splenocytes, and thymocytes.

Chemical analysis of new water-soluble (1→6)-, (1→4)-α, β-glucan and water-insoluble (1→3)-, (1→4)-β-glucan (Calocyban) from alkaline extract of an edible mushroom, Calocybe indica (Dudh Chattu)

Two different glucans (PS-I, water-soluble; and PS-II, water-insoluble) were isolated from the alkaline extract of fruit bodies of an edible mushroom Calocybe indica. On the basis of acid hydrolysis, methylation analysis, periodate oxidation, and NMR analysis ((1)H, (13)C, DEPT-135, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of these polysaccharides were established as: PS-I: →6)-β-D-Glcp-(1→6)-β-D-glcp-(1→6)-)-β-D-Glcp-(1→ α-D=Glcp (Water-soluble glucan). PS-II: →3)-β-D-Glcp-(1→3)-β-D-glcp-(1→3)-)-β-D-Glcp-(1→3)-β-D-Glcp-(1→ β-D-Glcp (Water-insoluble glucan, Calocyban).

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 10μg/mL. Structural investigation was carried out using sugar analysis, methylation analysis, periodate oxidation study, and NMR experiments ((1)H, (13)C, 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:

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 ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC and HMBC), the structure of the repeating unit of the polysaccharide was established as: [structure: see text].

Glucans of Pleurotus florida blue variant: isolation, purification, characterization and immunological studies.

Two different glucans (PS-I and PS-II) were isolated from the alkaline extract of the fruiting bodies of an edible mushroom, Pleurotus florida blue variant and the PS-I showed macrophage, splenocyte and thymocyte activations. On the basis of sugar analysis, methylation analysis, 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 these polysaccharides were established.

Structural characterization of a water-soluble β-(1→6)-linked d-glucan isolated from the hot water extract of an edible mushroom, Agaricus bitorquis

A water-soluble polysaccharide, isolated from the hot aqueous extract of an edible mushroom, Agaricus bitorquis, was found to consist of d-glucose only. On the basis of total hydrolysis, methylation analysis, and NMR studies ((1)H, (13)C, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit was established as -->6)-beta-D-Glcp-(1-->.