title: Novel arabinan and galactan oligosaccharides from dicotyledonous plants.
abstract: Arabinans and galactans are neutral pectic side chains and an important part of the cell walls of dicotyledonous plants. To get a detailed insight into their fine structure, various oligosaccharides were isolated from quinoa, potato galactan, and sugar beet pulp after enzymatic treatment. LC-MS(2) and one- and two-dimensional NMR spectroscopy were used for unambiguous structural characterization. It was demonstrated that arabinans contain β-(1→3)-linked arabinobiose as a side chain in quinoa seeds, while potato galactan was comprised of β-(1→4)-linked galactopyranoses which are interspersed with α-(1→4)-linked arabinopyranoses. Additionally, an oligosaccharide with two adjacent arabinofuranose units O2-substituted with two ferulic acid monomers was characterized. The isolated oligosaccharides gave further insight into the structures of pectic side chains and may have an impact on plant physiology and dietary fiber fermentation.
authors.affiliation: Department of Food Chemistry and Phytochemistry, Institute of Applied Biosciences, Karlsruhe Institute of Technology Karlsruhe, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Wefers
authors.affiliation: Department of Food Science and Nutrition, University of Minnesota St. Paul, MN, USA.
authors.forename: Catrin E
authors.initials: CE
authors.lastname: Tyl
authors.affiliation: Department of Food Chemistry and Phytochemistry, Institute of Applied Biosciences, Karlsruhe Institute of Technology Karlsruhe, Germany.
authors.forename: Mirko
authors.initials: M
authors.lastname: Bunzel
keywords: NMR; arabinans; cell wall; ferulic acid; galactans; oligosaccharides; pectin; polysaccharides