Structural investigation of a heteropolysaccharide isolated from the green fruits of Capsicum annuum

A water-soluble polysaccharide isolated from the hot water extract of the green fruits of Capsicum annuum was found to consist of 3-O-acyl-l-rhamnose, d-methyl galacturonate, 6-O-methyl-d-galactose in a molar proportion of nearly 1:2:1. Structural investigation of the polysaccharide was carried out using total hydrolysis, methylation analysis, periodate oxidation followed by GLC-MS, and NMR experiments. On the basis of the above-mentioned experiments it is concluded that the following repeating unit is present in the polysaccharide.     

Structural investigation of a heteropolysaccharide isolated from the pods (fruits) of Moringa oleifera (Sajina)

A water-soluble polysaccharide was isolated from the aqueous extract of pods of Moringa oleifera. The polysaccharide contains d-galactose, 6-O-Me-D-galactose, D-galacturonic acid, l-arabinose, and l-rhamnose in a molar ratio of 1:1:1:1:1. On the basis of total hydrolysis, methylation analysis, periodate oxidation, and NMR ((1)H, (13)C, TOCSY, DQF-COSY, NOESY, ROESY, HSQC, and HMBC) studies, the repeating unit of the polysaccharide is established as [structure: see text].     

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].     

Structural studies of a methyl galacturonosyl-methoxyxylan isolated from the stem of Lagenaria siceraria (Lau)

A water-soluble polysaccharide was isolated from the aqueous extract of the stem of Lagenaria siceraria. The polysaccharide was found to be constituted of methyl d-galacturonate, 2-O-methyl-D-xylose, and d-xylose in a ratio of 1:1:1. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, NMR studies ((1)H, (13)C, 2D-COSY, TOCSY, NOESY, HSQC, and HMBC), and MALDI-TOF MS analysis, the structure of the repeating unit of the polysaccharide is determined as.     

Structural characterization of a heteropolysaccharide isolated from hot water extract of the stems of Amaranthus tricolor Linn. (Amaranthus gangeticus L.)

A water-soluble polysaccharide (PS-I), isolated from the aqueous extract of the stems of Amaranthus tricolor Linn. (Amaranthus gangeticus L.), was found to consist of l-arabinose, methyl-d-galacturonate, d-galactose, and 3-O-Ac-l-rhamnose in a molar ratio of nearly 1:1:1:1. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, and NMR studies (¹H, ¹³C, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit of the PS-I is determined as:     

Structural investigation of a heteroglycan isolated from the fruit bodies of an ectomycorrhizal fungus Astraeus hygrometricus

A polysaccharide fraction (AQS-II) has been isolated from the hot aqueous extract of the fruits of an ectomycorrhizal fungus Astraeus hygrometricus. It was found to contain 63% polysaccharide and 35% protein. The polysaccharide part contains glucose, galactose, and fucose in a 2:1:1 molar ratio. On the basis of total acid hydrolysis, methylation analysis, periodate oxidation, and NMR studies ((1)H, (13)C, DQF-COSY, TOCSY, NOESY, HMBC, and HSQC) the structure of the repeating unit of the polysaccharide was established as [structure: see text].     

Structural characterization of a water-soluble beta-(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 (¹H, ¹³C, TOCSY, DQF-COSY, NOESY, ROESY, HMQC, and HMBC), the structure of the repeating unit was established as→6)-β-d-Glcp-(1→     

Structural elucidation and immuno-stimulating activity of an acidic heteropolysaccharide (TAPA1) from Tremella aurantialba

A novel acidic heteropolysaccharide (TAPA1) was purified from hot water extracts of Tremella aurantialba fruiting bodies by DEAE-Sepharose Fast Flow and Sephacryl S-500 High-Resolution Chromatography. The heteropolysaccharide had a molecular weight of ca. 1.35 × 10⁶ Da, and a carbohydrate content estimated to be ∼98.7% by the phenol-sulfuric acid method. It was composed mainly of d-mannose, d-xylose, and d-glucuronic acid in the ratio of ca. 5:4:1, along with trace amounts of d-galacturonic acid and d-glucose. Monosaccharide compositional analysis and GC-MS of methylated derivatives, combined with ¹H and ¹³C NMR spectroscopies (including COSY, TOCSY, NOESY, HSQC, and HMBC spectra), revealed TAPA1 to consist of an α-(1→3)-linked mannopyranosyl backbone, partially substituted at position 4 with xylose side chains, and at position 2 with side chains composed of either xylose, mannose, and glucuronic acid or of xylose and mannose. Bioactivity testing showed that TAPA1 stimulated the proliferation of mouse spleen lymphocytes in vitro.     

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].     

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 (¹H, ¹³C, 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.     

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.     

Structural elucidation of the polysaccharide moiety of a glycopeptide (GLPCW-II) from Ganoderma lucidum fruiting bodies

A water-soluble glycopeptide (GLPCW-II) was isolated from the fruiting bodies of Ganoderma lucidum by DEAE-Sepharose Fast-Flow and Sephacryl S-300 High Resolution Chromatography. The glycopeptide had a molecular weight of 1.2x10(4)Da (determined by HPLC), and consisted of approximately 90% carbohydrate and approximately 8% protein as determined using the phenol-sulfuric acid method and the BCA protein assay reagent kit, respectively. The polysaccharide moiety was composed mainly of D-Glc, L-Fuc, and D-Gal in the ratio of 1.00:1.09:4.09. To facilitate structure-activity studies, the structure of the GLPCW-II polysaccharide moiety was elucidated using 1H and 13C NMR spectroscopy including COSY, TOCSY, HMBC, HSQC, and ROESY, combined with GC-MS of methylated derivatives, and shown to consist of repeating units with the following structure: [Formula: see text].     

Structural features of an arabinogalactan gum exudates from Spondias dulsis (Anacardiaceae)

The tree Spondias dulcis, located in Venezuela, exudes a light-brown gum. The polysaccharide, isolated from the original gum, contains galactose, arabinose, mannose, rhamnose, glucuronic acid, and its 4-O-methyl derivative. Application of chemical methods, in combination with 1D and 2D NMR spectroscopy afforded interesting structural features of the gum polysaccharide. The unequivocal presence of rhamnose in the polymer structure was confirmed by chemical and spectral data [1H (1.03 ppm); 13C (16.92 ppm)]. Also confirmed was the existence of 3-O- and 6-O-substitutes galactose residues by the spectral data correlations observed in Heteronuclear Multiple Quantum Coherence (HMQC) and Heteronuclear Multiple Bond Correlation (HMBC). Also observed were unequivocal resonances for beta-D-glucuronic acid and its 4-O-methyl derivative, and the presence of 3-O-alpha-L-arabinofuranose and 3-O-beta-L-arabinopyranose residues.     

Structural investigation of a water-soluble glucan from an edible mushroom, Astraeus hygrometricus

A water-soluble glucan, Fraction I, was isolated from the aqueous extract of the fruit bodies of the mushroom Astraeus hygrometricus. On the basis of total hydrolysis, methylation analysis, periodate oxidation, and NMR studies ((1)H, (13)C, 2D-COSY, TOCSY, NOESY, and HSQC), the structure of the repeating unit of the glucan is determined as:This glucan shows strong splenocyte activation.     

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].     

Isolation and characterization of a heteroglycan from the fruits of Astraeus hygrometricus

A water-soluble polysaccharide was isolated from an alkaline extract of the fruits of the ectomycorrhizal fungus, Astraeus hygrometricus. It was found to contain D-mannose, D-glucose, and L-fucose in a molar ratio of 1:2:1. On the basis of total hydrolysis, methylation analysis, periodate oxidation, Smith degradation, and NMR studies (1H, 13C, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC) the structure of the repeating unit of the polysaccharide was established as [Formula: see text]     

Structural elucidation of a 3-O-methyl-D-galactose-containing neutral polysaccharide from the fruiting bodies of Phellinus igniarius

PIP60-1, a novel heteropolysaccharide isolated from fruiting bodies of the medicinal fungus, Phellinus igniarius, has a molecular weight of 1.71 x 10(4)Da and is composed of L-fucose, D-glucose, D-mannose, D-galactose and 3-O-Me-D-galactose in a ratio of 1:1:1:2:1. A structural investigation of PIP60-1 carried out using sugar and methylation analyses, combined with (1)H and (13)C NMR spectroscopy, including COSY, TOCSY, NOESY, HSQC and HMBC experiments, established the repeating unit of the polysaccharide as the following: [structure: see text]