Debsankar Das

Structural studies of an immunoenhancing water-soluble glucan isolated from hot water extract of an edible mushroom, Pleurotus florida, cultivar Assam Florida.

An immunoenhancing polysaccharide isolated from the hot water extract of the fruiting bodies of an edible mushroom Pleurotus florida, cultivar Assam Florida, was found to consist of only d-glucose as a monosaccharide constituent. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, Smith degradation, and NMR experiments ((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 This glucan stimulates macrophages, splenocytes, and thymocytes.

Structural analysis of a polysaccharide isolated from the aqueous extract of an edible mushroom, Pleurotus sajor-caju, cultivar Black Japan

A water-soluble polysaccharide, isolated from the aqueous extract of an edible mushroom Pleurotus sajor-caju, cultivar Black Japan was found to consist of D-glucose and D-galactose in a molar ratio of 3:1. On the basis of total acid hydrolysis, methylation analysis, and NMR experiments (1H, 13C, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) the structure of the polysaccharide was established as [Formula: see text].

Isolation and characterization of a heteropolysaccharide from the corm of Amorphophallus campanulatus

A water-soluble polysaccharide isolated from the aqueous extract of the corm of Amorphophallus campanulatus was found to contain D-galactose, D-glucose, 4-O-acyl-D-methyl galacturonate, and l-arabinose in a molar ratio 2:1:1:1. Structural investigation of the polysaccharide was carried out using acid hydrolysis, methylation analysis, periodate oxidation study, and NMR studies ((1)H, (13)C, DQF-COSY, TOCSY, 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 molecule showed splenocyte activation.

Structural characterization and study of immunoenhancing and antioxidant property of a novel polysaccharide isolated from the aqueous extract of a somatic hybrid mushroom of Pleurotus florida and Calocybe indica variety APK2.

A water-soluble polysaccharide was isolated from the aqueous extract of the fruit bodies of somatic hybrid PCH9FB, obtained through intergeneric protoplast fusion between the strains Pleurotus florida and Calocybe indica var. On the basis of total acid hydrolysis, the polysaccharide was found to contain galactose, fucose, and glucose in a molar ratio of nearly 2:1:2. Methylation analysis and NMR experiments ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) showed that the structure of the repeating unit present in the polysaccharide was This molecule showed macrophage, splenocyte, thymocyte activation as well as antioxidant property.

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].

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.

A (1→6)-β-glucan from a somatic hybrid of Pleurotus florida and Volvariella volvacea: isolation, characterization, and study of immunoenhancing properties

A water-soluble immunoenhancing polysaccharide was isolated from the aqueous extract of fruit bodies of somatic hybrid (Pflo Vv5 FB), obtained through protoplast fusion between Pleurotus florida and Volvariella volvacea strains. On the basis of acid hydrolysis, the polysaccharide was found to contain glucose only. Methylation analysis, periodate oxidation along with (1)H, DEPT-135, and (13)C NMR spectroscopy, including two-dimensional TOCSY, DQF-COSY, NOESY, ROESY, 1H,13C-HMQC, and HMBC experiments showed that the polysaccharide was a (1-->6)-beta-d-glucan, which was not a constituent of any of the parent mushrooms previously reported. This glucan stimulated the macrophages, splenocytes, and thymocytes.

Chemical analysis of a new fucoglucan isolated from an edible mushroom, Termitomyces robustus.

A water-soluble fucoglucan, isolated from alkali-treated edible mushroom, Termitomyces robustus, consists of L-fucose and D-glucose in a molar proportion of 1:4. Structural investigation of the polysaccharide was carried out by using total hydrolysis, methylation analysis, and periodate oxidation followed by GLC-MS, and the final structure was determined using NMR experiments (1H, 13C, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC). On the basis of the above experiments it is concluded that the following repeating unit is present in the polysaccharide: [Formula: see text].

Structural and immunological studies of hetero polysaccharide isolated from the alkaline extract of Tricholoma crassum (Berk.) Sacc.

An immunoenhancing water-soluble hetero polysaccharide was isolated from an alkaline extract of the fruit bodies of an ectomycorrhizal edible mushroom, Tricholoma crassum (Berk.) Sacc. The structure of the molecule was investigated using acid hydrolysis, methylation analysis; periodate oxidation study, and NMR spectroscopy techniques ((1)H, (13)C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HSQC, and HMBC). On the basis of the above-mentioned experiments the structure of the repeating unit of the polysaccharide was established as: This polysaccharide exhibited splenocyte, thymocyte as well as macrophage activations.

NMR and MALDI-TOFMS analysis of a heteroglycan isolated from hot water extract of edible mushroom, Volvariella bombycina.

A water-soluble polysaccharide, isolated from the hot aqueous extract of an edible mushroom, Volvariella bombycina, consists of d-glucose, d-mannose, and d-galactose in a molar ratio 2:1:1. On the basis of total hydrolysis, methylation analysis, periodate oxidation, and NMR studies ((1)H, (13)C, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), and MALDI-TOFMS analysis, the repeating unit of the polysaccharide is established as [table in text].