Ryoko Gonda

Characterization of two novel polysaccharides having immunological activities from the root of Panax ginseng.

Two acidic polysaccharides, called ginsenan S-IA and ginsenan S-IIA, were isolated from the root of Panax ginseng C. A. Meyer. They were homogeneous on electrophoresis and gel chromatography, and their molecular masses were estimated to be 5.6 x 10(4) and 1.0 x 10(5), respectively. Ginsenan S-IA is composed of L-arabinose: D-galactose: D-galacturonic acid in the molar ratio of 8:8:1, and ginsenan S-IIA is composed of L-arabinose: D-galactose: D-glucose: D-galacturonic acid in the molar ratio of 15:10:2:5, in addition to small amounts of O-acetyl groups. About a half (ginsenan S-IA) and about a quarter (ginsenan S-IIA) of the hexuronic acid residues exist as methyl esters. Reduction of carboxyl groups, methylation analysis, nuclear magnetic resonance and periodate oxidation studies indicated that their structural features include mainly alpha-1,5-linked L-arabino-beta-3,6-branched D-galactan type structural units. Both polysaccharides showed remarkable reticuloendothelial system-potentiating activity in a carbon clearance test and pronounced anti-complementary activity. These substances are the first examples having a relatively high content of both alpha-3,5-branched L-arabinose and beta-1,4-linked D-galactose units among the acidic arabinogalactans with activities on phagocytosis and anti-complement.

Glycan structures of ganoderans b and c, hypoglycemic glycans of ganoderma lucidum fruit bodies

Abstract Two hypoglycemic principles, ganoderans B and C, isolated from the fruit bodies of Ganoderma lucidum were shown to be peptidoglycans with M ,s of 7400 and 5800, respectively. Physico-chemical and chemical studies demonstrated that the backbone and side chains of ganoderan B contain D -glucopyranosyl β-1 → 3 and β-1 → 6 linkages while those of ganoderan C contain D -glucopyranosyl β-1 → 3 and β-1 → 6 linkages and a D -galactopyranosyl α-1 → 6 linkage.

Structure and anticomplementary activity of an acidic polysaccharide from the leaves of Malva sylvestris var. mauritiana

A main acidic polysaccharide preparation was isolated from the leaves of Malva sylvestris L. var mauritiana Mill. It is composed of L-rhamnose, D-galactose, D-galacturonic acid, and D-glucuronic acid in the molar ratio of 22:6:22:11, and it contains 7.7% peptide. It was homogeneous by electrophoresis and gel chromatography, which gave a value of 11,000 as molecular weight. The structure of the polysaccharide component was elucidated by methylation analysis and partial hydrolysis. The substance showed considerable anticomplementary activity.

Relationship between chemical structure and activating potencies of complement by an acidic polysaccharide, plantago-mucilage A, from the seed of Plantago asiatica

Abstract The structure-complement activation relationship of Plantago-mucilage A, a partially O -acetylated glucuronoarabinoxylan isolated from the seed of Plantago asiatica , has been studied. The anti-complementary activity was markedly enhanced when the polysaccharide was deacetylated, but carboxyl-reduction and partial acid hydrolysis had little effect. Periodate oxidation decreased, but subsequent reduction restored, the activity; the activity of this polyalcohol was not changed in the absence of Ca 2+ . When serum was incubated with the deacetylated polymer, more marked C4 consumption was observed in the presence of Ca 2+ than with Plantago-mucilage A, but the polyalcohol did not show any C4 consumption. After incubation of the serum with the polyalcohol in the absence of Ca 2+ , a cleavage of C3 in the serum was detected by immunoelectrophoresis and by the consumption of complement when rabbit erythrocytes were used in the assay system, and these effects were much higher than for the original polysaccharide. Although the product of carboxyl-reduction did not contain O -acetyl groups, its C4 consumption was almost the same as that of Plantago-mucilage A. Thus, the O -acetyl groups in Plantago-mucilage A prevent the activation of complement via the classical pathway but the carboxyl groups are essential for the activation. The polyalcohol increases the activation of complement via the alternative pathway, but decreases the activation via the classical pathway.

A reticuloendothelial system-activating glycan from the seeds of Malva verticillata

Abstract From the hot water extract of the seeds of Malva verticillata , a polysaccharide (MVS-IIIA) has been isolated by fractionation on DEAE-Sephadex A-25 followed by chromatography on Sephacryl S-500 and Con A-Sepharose columns. Chemical and spectroscopic studies established that the polysaccharide possesses mainly an α-1,5-Iinked l -arabino-3,6-β- d -galactan structure. α-1,3-Linked l -arabinopyranose, β-1,4-linked d -xylose and α-1,4-linked d -galacturonic acid residues were also identified as the component units. The polysaccharide showed remarkable reticuloendothelial system potentiating activity in the carbon clearance test.

A reticuloendothelial system activating glycan from the rhizomes of Curcuma longa.

Abstract From the hot water extract of the rhizomes of Curcuma longa , a glycan, named ukonan A, has been isolated by fractionation on DEAE-Sephadex A-25 followed by chromatography on Con A-Sepharose and Sephacryl S-300 columns. Chemical and spectroscopic studies established that the glycan possesses an α- l -arabino-3,6-β- d -galactan structure. α-1,3-Linked l -arabinopyranose, β-3,4-branched d -xylose, α-1,4-linked d -glucose, α-2,4-branched l -rhamnose and α-1,4-linked d -galacturonic acid residues were also identified as the component sugar units. The glycan showed remarkable reticuloendothelial system potentiating activity in the carbon clearance test.