araban and polygalacturonic-acid

Topics: Cell Wall; Cellulose; Chemical Phenomena; Chemistry; Galactans; Glucans; Glycoproteins; Models, Molecular; Pectins; Phytoalexins; Plant Cells; Plant Extracts; Plant Growth Regulators; Plant Physiological Phenomena; Plant Proteins; Plants; Polysaccharides; Protease Inhibitors; Sesquiterpenes; Terpenes; Xylans

Sugar beet pectins (SBPs) are known for their emulsifying properties, but it is yet unknown which structural elements are most important for functionality. Recent results indicated that the arabinose content has a decisive influence, but the approach applied did not allow causality to be established. In this study, a mostly intact SBP was selectively modified and the obtained pectins were analyzed for their molecular structure and their emulsifying properties. De-esterification only resulted in a moderate increase in droplet size. The length of the pectin backbone only influenced the emulsifying properties when the homogalacturonan backbone was cleaved to a higher extent. By using different arabinan-modifying enzymes, it was demonstrated that both higher portions and chain lengths of arabinans positively influence the emulsifying properties of SBPs. Therefore, we were able to refine the structure-function relationships for acid-extracted SBPs, which can be used to optimize extraction conditions.

Topics: Arabinose; Beta vulgaris; Esterification; Pectins

Platycodonis Radix is widely used as homology of medicine and food in China; polysaccharides are thought to be one of its functional constituents. In this study, a pectic polysaccharide, PGP-I-I, was obtained from the root of the traditional medicine plant Platycodon grandiflorus through ion exchange chromatography and gel filtration. This was characterized being mainly composed of 1,5-α-L-arabinan and both arabinogalactan type I (AG-I) and II chains linked to rhamnogalacturonan I (RG-I) backbone linked to longer galacturonan chains. In vitro bioactivity study showed that PGP-I-I could restore the intestinal cellular antioxidant defense under the condition of hydrogen peroxide (H

Topics: Animals; Antioxidants; Cell Line; Chromatography, Gel; Chromatography, Ion Exchange; Dietary Carbohydrates; Galactans; Hydrogen Peroxide; Pectins; Plant Extracts; Plant Roots; Platycodon; Polysaccharides; Swine

The contribution of ATR-FTIR spectroscopy to study cell wall polysaccharides (CWPs) was carefully investigated. The region 1800-800 cm

Topics: Cell Wall; Cellulose; Galactans; Monosaccharides; Pectins; Plants; Polysaccharides; Principal Component Analysis; Spectroscopy, Fourier Transform Infrared

Plant cell walls contain cellulose embedded in matrix polysaccharides. Understanding carbohydrate structures and interactions is critical to the production of biofuel and biomaterials using these natural resources. Here we present a solid-state NMR study of cellulose and pectin in

Topics: Arabidopsis; Cell Wall; Cellulose; Magnetic Resonance Spectroscopy; Methyltransferases; Pectins; Polysaccharides

The chemical structure of pea pectin was delineated using pectin-degrading enzymes and biochemical methods. The molecular weight of the pea pectin preparation was 488,000, with 50 % arabinose content, and neutral sugar side chains attached to approximately 60 % of the rhamnose residues in rhamnogalacturonan-I (RG-I). Arabinan, an RG-I side chain, was highly branched, and the main chain was comprised of α-1,5-l-arabinan. Galactose and galactooligosaccharides were attached to approximately 35 % of the rhamnose residues in RG-I. Long chain β-1,4-galactan was also present. The xylose substitution rate in xylogalacturonan (XGA) was 63 %. The molar ratio of RG-I/homogalacturonan (HG)/XGA in the backbone of the pea pectin was approximately 3:3:4. When considering neutral sugar side chain content (arabinose, galactose, and xylose), the molar ratio of RG-I/HG/XGA regions in the pea pectin was 7:1:2. These data will help understand the properties of pea pectin.

Topics: Arabinose; Galactans; Galactose; Glycoside Hydrolases; Hexuronic Acids; Molecular Structure; Pectins; Pisum sativum; Polysaccharides; Rhamnose; Xylose

Exotic fruits and their co-products may be valuable sources of antioxidant dietary fibres (DF) which are useful for food industry and human health. In this study, we aimed to characterize DF obtained from guavira fruit pomace and investigate its antioxidant potential employing TEAC assay as well as a cell model. The DF were chemically characterized as containing arabinan, highly-methoxylated homogalacturonan and arabinogalactan. The DF-containing fraction (CPW) presented ABTS free radical scavenger activity. MTT and DCFH-DA assay were performed to assess, respectively, changes in cell viability and the potential intracellular antioxidant activity against H

Topics: Animals; Antioxidants; Cell Survival; Dietary Fiber; Fibroblasts; Fruit; Galactans; Hydrogen Peroxide; Mice; NIH 3T3 Cells; Oxidative Stress; Pectins; Polysaccharides

Topics: Blood Proteins; Cell Membrane; Cell Wall; Citrus; Fruit; Galactans; Galectins; Humans; Hydrolysis; MCF-7 Cells; Pectins; Plant Cells; Polysaccharides; Protein Binding; Solubility; Structure-Activity Relationship; Water

The aim of this study was to investigate the chemical structure and biological activity of a pectic fraction isolated from the aerial parts of A. campestris L. subsp. maritima Arcangeli. The chemical and spectroscopic analyses of the pectic fraction (ACP-E10) demonstrated that ACP-E10 was composed of homogalacturonan (HG) (60%) and rhamnogalacturonan-I (RG-I) (29%) regions. Side chains of the RG-I included mainly branched arabinans and type II arabinogalactans (AG-II). The molar mass of ACP-E10 determined by HPSEC-MALLS was 16,600g/mol. ACP-E10 was evaluated for its gastroprotective effect against ethanol-induced gastric lesions in rats. Oral pretreatment of animals with ACP-E10 (0.3, 3 and 30mg/kg) significantly reduced gastric lesions by 77±7.9%, 55±11.1% and 65±11.8%. ACP-E10 also maintained mucus and glutathione (GSH) contents in the gastric mucosa. In addition, ACP-E10 demonstrated antioxidant activity in vitro by the DPPH assay. These results demonstrated that the pectin from A. campestris had significant gastroprotective effects in vivo, which were likely attributable to their capacity to increase the protective defenses of gastric mucosa.

Topics: Animals; Anti-Ulcer Agents; Artemisia; Ethanol; Gastric Mucosa; Humans; Mucoproteins; Pectins; Phytotherapy; Plant Leaves; Plant Proteins; Polysaccharides; Rats; Stomach Ulcer

Primary cell wall polysaccharides from aqueous extract of buriti fruit pulp (Mauritia flexuosa, an exotic tropical palm) were isolated and characterized. After freeze-thaw and α-amylase treatments, extracted polysaccharides were purified by sequential ultrafiltration through membranes. Two homogeneous fractions were obtained, SBW-100R and SBW-30R (Mw of 126 kDa and 20 kDa, respectively). Monosaccharide composition, methylation and (13)C NMR analysis showed that fraction SBW-100R contained a (1 → 5)-linked arabinan, branched at O-3 and O-2 positions, linked to a type I rhamnogalacturonan. Low amounts of these polymers were also present in fraction SBW-30R according to (13)C NMR analysis and monosaccharide composition. However, a high methyl esterified homogalacturonan (HG) was present in higher proportions. These results reinforce previous findings present in literature data which indicate that pectic polysaccharides are found in high amounts in primary cell walls of palms, which are commelinid monocotyledons.

Topics: Arecaceae; Cell Wall; Fruit; Magnetic Resonance Spectroscopy; Molecular Structure; Monosaccharides; Pectins; Plant Extracts; Polysaccharides

While it is kno3wn that complex tissues with specialized functions emerged during land plant evolution, it is not clear how cell wall polymers and their structural variants are associated with specific tissues or cell types. Moreover, due to the economic importance of many flowering plants, ferns have been largely neglected in cell wall comparative studies.. To explore fern cell wall diversity sets of monoclonal antibodies directed to matrix glycans of angiosperm cell walls have been used in glycan microarray and in situ analyses with 76 fern species and four species of lycophytes. All major matrix glycans were present as indicated by epitope detection with some variations in abundance. Pectic HG epitopes were of low abundance in lycophytes and the CCRC-M1 fucosylated xyloglucan epitope was largely absent from the Aspleniaceae. The LM15 XXXG epitope was detected widely across the ferns and specifically associated with phloem cell walls and similarly the LM11 xylan epitope was associated with xylem cell walls. The LM5 galactan and LM6 arabinan epitopes, linked to pectic supramolecules in angiosperms, were associated with vascular structures with only limited detection in ground tissues. Mannan epitopes were found to be associated with the development of mechanical tissues. We provided the first evidence for the presence of MLG in leptosporangiate ferns.. The data sets indicate that cell wall diversity in land plants is multifaceted and that matrix glycan epitopes display complex spatio-temporal and phylogenetic distribution patterns that are likely to relate to the evolution of land plant body plans.

Topics: Antibodies, Monoclonal; Cell Wall; Epitopes; Ferns; Fluorescent Antibody Technique, Indirect; Galactans; Glucans; Mannans; Microarray Analysis; Organ Specificity; Pectins; Phloem; Phylogeny; Plant Extracts; Polysaccharide-Lyases; Polysaccharides; Xylans

In seed plants, the ability of guard cell walls to move is imparted by pectins. Arabinan rhamnogalacturonan I (RG1) pectins confer flexibility while unesterified homogalacturonan (HG) pectins impart rigidity. Recognized as the first extant plants with stomata, mosses are key to understanding guard cell function and evolution. Moss stomata open and close for only a short period during capsule expansion. This study examines the ultrastructure and pectin composition of guard cell walls during development in Funaria hygrometrica and relates these features to the limited movement of stomata.. Developing stomata were examined and immunogold-labelled in transmission electron microscopy using monoclonal antibodies to five pectin epitopes: LM19 (unesterified HG), LM20 (esterified HG), LM5 (galactan RG1), LM6 (arabinan RG1) and LM13 (linear arabinan RG1). Labels for pectin type were quantitated and compared across walls and stages on replicated, independent samples.. Walls were four times thinner before pore formation than in mature stomata. When stomata opened and closed, guard cell walls were thin and pectinaceous before the striated internal and thickest layer was deposited. Unesterified HG localized strongly in early layers but weakly in the thick internal layer. Labelling was weak for esterified HG, absent for galactan RG1 and strong for arabinan RG1. Linear arabinan RG1 is the only pectin that exclusively labelled guard cell walls. Pectin content decreased but the proportion of HG to arabinans changed only slightly.. This is the first study to demonstrate changes in pectin composition during stomatal development in any plant. Movement of Funaria stomata coincides with capsule expansion before layering of guard cell walls is complete. Changes in wall architecture coupled with a decrease in total pectin may be responsible for the inability of mature stomata to move. Specialization of guard cells in mosses involves the addition of linear arabinans.

Topics: Biological Evolution; Bryopsida; Cell Wall; Pectins; Plant Stomata; Polysaccharides

To enable structural characteristics of individual cell wall polysaccharides from rapeseed (Brassica napus) meal (RSM) to be studied, polysaccharide fractions were sequentially extracted. Fractions were analysed for their carbohydrate (linkage) composition and polysaccharide structures were also studied by enzymatic fingerprinting. The RSM fractions analysed contained pectic polysaccharides: homogalacturonan in which 60% of the galacturonic acid residues are methyl-esterified, arabinan branched at the O-2 position and arabinogalactan mainly type II. This differs from characteristics previously reported for Brassica campestris meal, another rapeseed cultivar. Also, in the alkali extracts hemicelluloses were analysed as xyloglucan both of the XXGG- and XXXG-type decorated with galactosyl, fucosyl and arabinosyl residues, and as xylan with O-methyl-uronic acid attached. The final residue after extraction still contained xyloglucan and remaining (pectic) polysaccharides next to cellulose, showing that the cell wall matrix of RSM is very strongly interconnected.

Topics: Brassica napus; Carbohydrate Sequence; Cell Wall; Chromatography, Ion Exchange; Enzyme Assays; Galactans; Glucans; Hexuronic Acids; Molecular Sequence Data; Pectins; Polysaccharides; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Xylans

Plant cell wall polysaccharides vary in quantity and structure between different organs and during development. However, quantitative analysis of individual polysaccharides remains challenging, and relatively little is known about any such variation in polysaccharides in organs of the model plant Arabidopsis thaliana. We have analysed plant cell wall pectic polysaccharides using polysaccharide analysis by carbohydrate gel electrophoresis. By highly specific enzymatic digestion of a polysaccharide in a cell wall preparation, a unique fingerprint of short oligosaccharides was produced. These oligosaccharides gave quantitative and structural information on the original polysaccharide chain. We analysed enzyme-accessible polygalacturonan (PGA), linear beta(1,4) galactan and linear alpha(1,5) arabinan in several organs of Arabidopsis: roots, young leaves, old leaves, lower and upper inflorescence stems, seeds and callus. We found that this PGA constitutes a high proportion of cell wall material (CWM), up to 15% depending on the organ. In all organs, between 60 and 80% of the PGA was highly esterified in a blockwise fashion, and surprisingly, dispersely esterified PGA was hardly detected. We found enzyme-accessible linear galactan and arabinan are both present as a minor polysaccharide in all the organs. The amount of galactan ranged from ~0.04 to 0.25% of CWM, and linear arabinan constituted between 0.015 and 0.1%. Higher levels of galactan correlated with expanding tissues, supporting the hypothesis that this polysaccharide is involved in wall extension. We show by analysis of mur4 that the methods and results presented here also provide a basis for studies of pectic polysaccharides in Arabidopsis mutants.

Topics: Arabidopsis; Arabidopsis Proteins; Carbohydrate Epimerases; Cell Wall; Electrophoresis, Polyacrylamide Gel; Galactans; Hydrolases; Pectins; Plant Leaves; Plant Roots; Plant Stems; Polysaccharides; Seeds

Cnr (colorless non-ripening) is a pleiotropic tomato (Lycopersicon esculentum) fruit ripening mutant with altered tissue properties including weaker cell-to-cell contacts in the pericarp (A.J. Thompson, M. Tor, C.S. Barry, J. Vrebalov, C. Orfila, M.C. Jarvis, J.J. Giovannoni, D. Grierson, G.B. Seymour [1999] Plant Physiol 120: 383-390). Whereas the genetic basis of the Cnr mutation is being identified by molecular analyses, here we report the identification of cell biological factors underlying the Cnr texture phenotype. In comparison with wild type, ripe-stage Cnr fruits have stronger, non-swollen cell walls (CW) throughout the pericarp and extensive intercellular space in the inner pericarp. Using electron energy loss spectroscopy imaging of calcium-binding capacity and anti-homogalacturonan (HG) antibody probes (PAM1 and JIM5) we demonstrate that maturation processes involving middle lamella HG are altered in Cnr fruit, resulting in the absence or a low level of HG-/calcium-based cell adhesion. We also demonstrate that the deposition of (1-->5)-alpha-L-arabinan is disrupted in Cnr pericarp CW and that this disruption occurs prior to fruit ripening. The relationship between the disruption of (1-->5)-alpha-L-arabinan deposition in pericarp CW and the Cnr phenotype is discussed.

Topics: Microscopy, Electron, Scanning; Mutation; Pectins; Polysaccharides; Solanum lycopersicum