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.
Tomoda
M
M
Kyoritsu College of Pharmacy, Tokyo, Japan.
Hirabayashi
K
K
Shimizu
N
N
Gonda
R
R
Ohara
N
N
Takada
K
K
D001089:Arabinose / Q000032:analysis; D002240:Carbohydrate Sequence; D002849:Chromatography, Gas; D002850:Chromatography, Gel; D002855:Chromatography, Thin Layer; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification*; D004590:Electrophoresis, Paper; D005690:Galactose / Q000032:analysis; D005947:Glucose / Q000032:analysis; D006603:Hexuronic Acids / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D008745:Methylation; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010084:Oxidation-Reduction; D005894:Panax / Q000737:chemistry*; D010946:Plants, Medicinal; D011134:Polysaccharides / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D013237:Stereoisomerism
D004365:Drugs, Chinese Herbal; D006603:Hexuronic Acids; D011134:Polysaccharides; C007819:galacturonic acid; D001089:Arabinose; D005947:Glucose; D005690:Galactose