title: Immunomodulating pectins from root bark, stem bark, and leaves of the Malian medicinal tree Terminalia macroptera, structure activity relations.
abstract: The root bark, stem bark, and leaves of Terminalia macroptera were sequentially extracted with ethanol, 50% ethanol-water, and 50°C water using an accelerated solvent extractor (ASE). Six bioactive purified pectic polysaccharide fractions were obtained from the 50°C crude water extracts after anion exchange chromatography and gel filtration. The root bark, stem bark, and leaves of T. macroptera were all good sources for fractions containing bioactive polysaccharides. The high molecular weight fraction 50WTRBH-I-I, being the most active fraction in the complement fixation test, has a highly ramified rhamnogalacturonan type I (RG-I) region with arabinogalactan type II (AG-II) side chains. The most abundant fractions from each plant part, 50WTRBH-II-I, 50WTSBH-II-I, and 50WTLH-II-I, were chosen for pectinase degradation. The degradation with pectinase revealed that the main features of these fractions are that of pectic polysaccharides, with hairy regions (RG-I regions) and homogalacturonan regions. The activity of the fractions obtained after pectinase degradation and separation by gel filtration showed that the highest molecular weight fractions, 50WTRBH-II-Ia, 50WTSBH-II-Ia, and 50WTLH-II-Ia, had higher complement fixation activity than their respective native fractions. These results suggest that the complement fixation activities of these pectins are expressed mainly by their ramified regions.
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 1068, Blindern, 0316 Oslo, Norway.
authors.forename: Yuan-Feng
authors.initials: YF
authors.lastname: Zou
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 1068, Blindern, 0316 Oslo, Norway.
authors.forename: Hilde
authors.initials: H
authors.lastname: Barsett
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 1068, Blindern, 0316 Oslo, Norway.
authors.forename: Giang Thanh Thi
authors.initials: GT
authors.lastname: Ho
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 1068, Blindern, 0316 Oslo, Norway.
authors.forename: Kari Tvete
authors.initials: KT
authors.lastname: Inngjerdingen
authors.affiliation: Department of Traditional Medicine, BP 1746 Bamako, Mali.
authors.forename: Drissa
authors.initials: D
authors.lastname: Diallo
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 1068, Blindern, 0316 Oslo, Norway.
authors.forename: Terje Einar
authors.initials: TE
authors.lastname: Michaelsen
authors.affiliation: Department of Pharmaceutical Chemistry, School of Pharmacy, University of Oslo, PO Box 1068, Blindern, 0316 Oslo, Norway. Electronic address: b.s.paulsen@farmasi.uio.no.
authors.forename: Berit Smestad
authors.initials: BS
authors.lastname: Paulsen
mesh_terms: D002240:Carbohydrate Sequence; D003165:Complement System Proteins / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007155:Immunologic Factors / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D008969:Molecular Sequence Data; D009005:Monosaccharides / Q000032:analysis; D010368:Pectins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D024301:Plant Bark / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D011096:Polygalacturonase / Q000378:metabolism; D013329:Structure-Activity Relationship; D029766:Terminalia / Q000737:chemistry*; D014197:Trees / Q000737:chemistry*
chemical_list: D007155:Immunologic Factors; D009005:Monosaccharides; D010368:Pectins; D003165:Complement System Proteins; D011096:Polygalacturonase
keywords: Complement fixation activity; Pectins; Rhamnogalacturonan I; Terminalia macroptera