Shigeo Ukai

Anti-inflammatory activity and conformational behavior of a branched (1→3)-β-d-glucan from an alkaline extract of dictyophora indusiata fisch☆

A (1→6)-branched (1→3)-β-d-glucan (T-5-N), isolated from a m sodium hydroxide extract of the fruit bodies of Dictyophora indusiata Fisch., markedly exhibited anti-inflammatory effects on both carrageenan-induced edema and scalded edematous hyperalgesia in rats hindpaws. The activities of T-5-N (25 mg/kg i.p. × 2) were more potent than those of phenylbutazone (25–50 mg/kg i.p. × 2). The conformational behavior of T-5-N was studied. Its molecular weight in neutral solution was about three times that in 0.25m sodium hydroxide. This finding, in addition to the results of optical rotatory measurement and complex-formation with Congo Red, indicated that T-5-N has an ordered, triple-helical structure in neutral or slightly alkaline solution (< 0.15m NaOH), and has single chains in highly alkaline solution (0.25m NaOH). The conformational transition occurs at concentrations of sodium hydroxide in the range of 0.15–0.25m.

(1→3)-α-d-glucan from an alkaline extract of Agrocybe cylindracea, and antitumor activity of its O-(carboxymethyl)ated derivatives

The structure of an alkali-soluble D-glucan (AG-AL) from the fruit body of Agrocybe cylindracea was investigated by a combination of chemical and spectroscopic methods indicating that it was a linear (1----3)-alpha-D-glucan (molecular weight, approximately 560,000), [alpha]20D +195 degrees (c 0.5, M sodium hydroxide). Both water-soluble and gelatinous products obtained by O-(carboxymethyl)ation of AG-AL showed potent antitumor activity against the solid form of Sarcoma 180 in mice, although the native D-glucan had little effect on the tumor.

Structure and antitumor activity of a branched (1→3)-β-d-glucan from the alkaline extract of Amanita muscaria☆

A beta-(1----6)-branched (1----3)-beta-D-glucan(AM-ASN) was isolated from the alkaline extract of the fruiting bodies of Amanita muscaria. AM-ASN had [alpha]D - 11 degrees in 0.5 M sodium hydroxide. Its estimated molecular weight was 95,000 in this alkaline solution and 260,000 in a neutral solution. The branches in the glucan were primarily single, (1----6)-linked D-glucopyranosyl groups, two for every seven residues in the (1----3)-linked main chain. AM-ASN exhibited significant antitumor activity against Sarcoma 180 in mice, and a mixture of AM-ASN with mitomycin C was more effective against the tumor than mitomycin C only.

A minor, protein-containing galactomannan from a sodium carbonate extract of Cordyceps sinensis☆

Abstract A water-soluble, minor, protein-containing galactomannan (CT-4N), [α] D −29.6°, isolated from a 5% sodium carbonate extract of Cordyceps sinensis , showed a homogeneous pattern in gel filtration and one spot in glass-fiber paper-electrophoresis. The molecular weight was estimated by gel filtration to be ∼23,000. It was mainly composed of d -mannose and d -galactose in the molar ratio of 3:5, and contained a small proportion of protein. From the results of methylation analysis, Smith degradation, stepwise hydrolysis, and 13 C-n.m.r. spectroscopy, it was concluded that the polysaccharide has a highly branched structure, and is composed of (1→6)- and (1→2)-linked α- d -mannopyranosyl residues in the main chain. Some of the residues are present as branching points of (1→2,6) and (1→4,6) linkages and the branches contain short chains having a large proportion of (1→5)-linked β- d -galactofuranosyl residues and a small proportion of (1→6)-linked α- d -galactopyranosyl resdues, and the (nonreducing) terminal groups consist of a large proportion of β- d -galactofuranosyl and a small proportion of α- d -mannopyranosyl groups.

A branched (1→3)-β-d-glucan from a sodium carbonate extract of Dictyophora indusiata fisch

Abstract A water-soluble, (1→6)-branched, (1→3)-β- d -glucan (T-4-N), [α] D 20 +19° ( c 0.1, water), was isolated from a 2% sodium carbonate extract of the fruit bodies of Dictyophora indusiata Fisch. T-4-N was homogeneous as judged by gel filtration, Tiselius-type electrophoresis, and ultracentrifugal analysis. By gel filtration on Sepharose CL-2B, with 0.25 m sodium hydroxide as the eluant, the molecular weight of T-4-N was estimated to be ∼5.5 × 10 6 . From the results of methylation analysis, periodate oxidation, Smith degradation (complete, and also mild), partial acetolysis, and enzymic degradation, it was concluded that T-4-N has a main chain composed of β-(1→3)-linked d -glucopyranosyl residues, and two single, β-(1→6)-linked d -glucopyranosyl groups attached as side chains to, on average, every fifth sugar residue of the main chain. In addition, the results of the enzymic hydrolysis suggested that the β-(1→6)-linked d -glucosyl side chains are mainly localized in the neighborhood of the nonreducing end of the main chain. The results of optical rotatory measurement and complex-formation with Congo Red indicated that T-4-N probably takes a triple-helical conformation.

Structure of a new galactomannan from the ascocarps of Cordyceps cicadae shing

Abstract A water-soluble galactomannan (C-3), [α] D 20 +30°, isolated from the rod-like ascocarps of Cordyceps cicadae , was determined to be homogeneous, and the molecular weight was estimated by gel filtration to be 27,000. The polysaccharide is composed of d -mannose and d -galactose in the molar ratio of 4:3. The results of methylation analysis, Smith degradation, stepwise hydrolysis with acid, and 13 C-n.m.r. spectroscopy indicated that the polysaccharide is of highly branched structure, and composed of α- d -(1→2)-linked and α- d -(1→6)-linked mannopyranosyl residues in the core; some of these residues are substituted at O-6 and O-2 with terminal β- d -galactofuranosyl and α- d -mannopyranosyl groups, and with short chains of β- d -(1→2)-linked d -galactofuranosyl units.

Structure of an alkali-soluble polysaccharide from the fruit body of Ganoderma japonicum Lloyd

Abstract A water-insoluble glucan (G-A), [α]D16 + 12.8° (c 0.4, m sodium hydroxide), was isolated from the alkaline extract of the fruit body of Ganoderma japonicum. G-A was homogeneous as judged by gel filtration, electrophoresis, and ultracentrifugal analysis. The molecular weight and degree of polymerization of G-A were respectively estimated to be 82,000 and 330. The 1H-n.m.r. and i.r. spectra, together with the result of chromium trioxide oxidation, indicated that the glucosidic linkages in G-A have the β- d configuration. From the results of methylation analysis, periodate oxidation, Smith degradation, and partial hydrolysis with acid, it was concluded that G-A is composed of a backbone of β-(1 → 3)-linked d -glucopyranosyl residues, and has side-chains of single, β-(1 → 6)-linked d -glucopyranosyl groups attached, on average, to every 30th residue of the backbone.

The location of the O-acetyl groups in the (1→3)-α-d-mannan from Dictyophora indusiata fisch

Abstract A linear (1→3)-α- d -mannan (T-2-HN) isolated from the hot, 70% aqueous ethanol extract of the fruit bodies of Dictyophora indusiata Fisch. contained about one O-acetyl group per two d -mannosyl residues in the molecule. The locations of the O-acetyl groups were elucidated by the methyl-replacement method involving the use of (1-methoxyethyl) protecting groups. The results indicated that most of the acetyl groups (∼88%) are located solely at O-6 of the α-(1→3)-linked d -mannopyranosyl residues in T-2-HN. In addition, small proportions of acetyl group are located on O-2,6, O-4,6, O-2, and O-4 of the d -mannosyl residues, and this conclusion was well supported by the results of a 13C-n.m.r.-spectral study. The molecular weights ( M w) of T-2-HN and its deacetylated product (water-insoluble) were, by gel chromatography on Sepharose CL-2B with 0.1 m sodium chloride and 2 m sodium hydroxide as the eluants, respectively determined to be 620,000 and 550,000.

A branched (1→3)-β-d-glucan from a water extract of Dictyophora indusiata Fisch

Abstract A water-soluble, (1→6)-branched, (1→3)-β- d -glucan (T-3-G), [α]D27 +40.8° (c 0.123, water), was isolated from a hot-water extract of the fruit bodies of Dictyophora indusiata Fisch. T-3-G was homogeneous as judged by ultracentrifugal analysis, Tiselius-type electrophoresis, and gel filtration. By gel filtration on Sepharose CL-2B, with 0.25 m sodium hydroxide as the eluant, the molecular weight ( M w) of T-3-G was estimated to be ∼5.1 × 105. From the results of methylation analysis, periodate oxidation, Smith degradation, and enzymic hydrolysis, it was concluded that T-3-G has a main chain composed of β-(1→3)-linked d -glucopyranosyl residues, and two single, β-(1→6)-linked d -glucopyranosyl groups attached as side chains to, on average, every five sugar residues of the main chain. In addition, the results of enzymic hydrolysis indicated that the branching of T-3-G occurs regularly at O-6 of the β-(1→3)-linked backbone. The results of optical rotatory measurements and complex-formation with Congo Red suggested that T-3-G probably takes a triple-helical conformation.

The decrease of thaumatin's sweetness intensity upon interaction with carrageenan

Abstract Carrageenan was added at various ratios to thaumatin, a sweet protein, and the interactions between thaumatin and λ−, κ− and ι-carrageenan were investigated from the following standpoints: pH, turbidity at 550 nm, CD spectral change (Δ∈) and the decrease in sweetness intensity. Decrease in thaumatin sweetness intensity was observed with lower pH ( κ-carrageenan. There was no correlation between sweetness intensity decrease and turbidity. With the increase in carrageenan concentration, CD spectral change (Δ∈) was distinctly observed at pH 3–4. Thaumatins sweetness intensity decreased simultaneously.