title: Relationship between structure and activity of the "ramified" region in anti-complementary pectic polysaccharides from Angelica acutiloba Kitagawa.
abstract: One of the anti-complementary pectic polysaccharides (AR-2IIa) isolated from the root of Angelica acutiloba Kitagawa gives the "ramified" region (PG-1a,rhamnogalacturonan with neutral side-chains) in addition to oligogalacturonides on digestion with endo-alpha-D-(1--4)-polygalacturonase. When the neutral side-chains in PG-1a were digested with both exo-alpha-L-arabinofuranosidase and exo-beta-D-galactosidase, approximately 70% of the arabinosyl chains and approximately 30% of the galactosyl chains were released. The resistant product E-PG-1a had the same anti-complementary activity as PG-1a. E-PG-1a gave long (d.p. greater than or equal to 5) and short (d.p. less than or equal to 4) neutral galactosyl chains after degradation of the GalA moiety by base-catalysed beta-elimination in the presence of sodium borodeuteride followed with lithium-mediated degradation. Methylation analysis showed that the long galactosyl chains consisted mainly of terminal, 6-linked and 3,6-disubstituted Gal, and that the short chains were rich in 6-linked Gal. Degradation of the GalA moieties in PG-1a markedly decreased the anti-complementary activity, but the long and short galactosyl chains still expressed approximately 50 and approximately 20%, respectively, of the anti-complementary activity of E-PG-1a.
authors.affiliation: Oriental Medicine Research Center of the Kitasato Institute, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kiyohara
authors.forename: J C
authors.initials: JC
authors.lastname: Cyong
authors.forename: H
authors.initials: H
authors.lastname: Yamada
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D015941:Complement Hemolytic Activity Assay; D003169:Complement Inactivator Proteins; D008401:Gas Chromatography-Mass Spectrometry; D066298:In Vitro Techniques; D008745:Methylation; D008969:Molecular Sequence Data; D010368:Pectins / Q000494:pharmacology*; D010944:Plants / Q000032:analysis*; D012756:Sheep; D013329:Structure-Activity Relationship
chemical_list: D003169:Complement Inactivator Proteins; D010368:Pectins; C003181:polygalacturonic acid