title: Characterization of cereal β-glucan extracts from oat and barley and quantification of proteinaceous matter.
abstract: An extraction method for mixed-linkage β-glucan from oat and barley was developed in order to minimize the effect of extraction on the β-glucan structure. β-Glucan were characterized in terms of molecular size and molar mass distributions using asymmetric flow field-flow fractionation (AF4) coupled to multiangle light scattering (MALS), differential refractive index (dRI) and fluorescence (FL) detection. The carbohydrate composition of the extracts was analysed using polysaccharide analysis by carbohydrate gel electrophoresis (PACE) and high-performance anion-exchange chromatography (HPAEC). Whether there were any proteinaceous moieties linked to β-glucan was also examined. Purified extracts contained 65% and 53% β-glucan for oats and barley, respectively. The main impurities were degradation products of starch. The extracts contained high molecular weight β-glucan (105-108 g/mol) and large sizes (root-mean-square radii from 20 to 140 nm). No proteins covalently bound to β-glucan were detected; therefore, any suggested functionality of proteins regarding the health benefits of β-glucan can be discounted.
authors.affiliation: Department of Food Technology, Engineering and Nutrition, Lund University, Lund, Sweden.
authors.forename: Claudia
authors.initials: C
authors.lastname: Zielke
authors.affiliation: Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, United Kingdom.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Kosik
authors.affiliation: European Spallation Source ESS AB, Lund, Sweden.
authors.forename: Marie-Louise
authors.initials: ML
authors.lastname: Ainalem
authors.affiliation: Department of Plant Biology and Crop Science, Rothamsted Research, West Common, Harpenden, United Kingdom.
authors.forename: Alison
authors.initials: A
authors.lastname: Lovegrove
authors.affiliation: Department of Physical Chemistry, Lund University, Lund, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Stradner
authors.affiliation: Department of Food Technology, Engineering and Nutrition, Lund University, Lund, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Nilsson
mesh_terms: D018554:Avena / Q000737:chemistry*; D002523:Edible Grain / Q000737:chemistry*; D001467:Hordeum / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry*; D010940:Plant Proteins / Q000032:analysis*; D011509:Proteoglycans / Q000032:analysis*
chemical_list: D010936:Plant Extracts; D010940:Plant Proteins; D011509:Proteoglycans