title: Differential effects of genetically distinct mechanisms of elevating amylose on barley starch characteristics.
abstract: The relationships between starch structure and functionality are important in underpinning the industrial and nutritional utilisation of starches. In this work, the relationships between the biosynthesis, structure, molecular organisation and functionality have been examined using a series of defined genotypes in barley with low (<20%), standard (20-30%), elevated (30-50%) and high (>50%) amylose starches. A range of techniques have been employed to determine starch physical features, higher order structure and functionality. The two genetic mechanisms for generating high amylose contents (down-regulation of branching enzymes and starch synthases, respectively) yielded starches with very different amylopectin structures but similar gelatinisation and viscosity properties driven by reduced granular order and increased amylose content. Principal components analysis (PCA) was used to elucidate the relationships between genotypes and starch molecular structure and functionality. Parameters associated with granule order (PC1) accounted for a large percentage of the variance (57%) and were closely related to amylose content. Parameters associated with amylopectin fine structure accounted for 18% of the variance but were less closely aligned to functionality parameters.
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Regina
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Blazek
authors.affiliation: Bragg Institute, Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232, Australia.
authors.forename: Elliot
authors.initials: E
authors.lastname: Gilbert
authors.affiliation: Centre for Nutrition and Food Sciences, University of Queensland, St. Lucia, Qld 4072, Australia.
authors.forename: Bernadine M
authors.initials: BM
authors.lastname: Flanagan
authors.affiliation: Centre for Nutrition and Food Sciences, University of Queensland, St. Lucia, Qld 4072, Australia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gidley
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
authors.forename: Colin
authors.initials: C
authors.lastname: Cavanagh
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Ral
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
authors.forename: Oscar
authors.initials: O
authors.lastname: Larroque
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Food and Nutritional Sciences, Kintore Avenue, Adelaide, SA, Australia.
authors.forename: Anthony R
authors.initials: AR
authors.lastname: Bird
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
authors.forename: Zhongyi
authors.initials: Z
authors.lastname: Li
authors.affiliation: CSIRO Food Futures National Research Flagship, GPO Box 1600, Canberra, ACT 2601, Australia; CSIRO Plant Industry, GPO Box 1600, Canberra, ACT 2601, Australia.
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Morell
mesh_terms: D000688:Amylose / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002850:Chromatography, Gel; D019075:Electrophoresis, Capillary; D017343:Genes, Plant; D001467:Hordeum / Q000737:chemistry / Q000235:genetics*; D010710:Phosphates / Q000378:metabolism; D025341:Principal Component Analysis; D012542:Scattering, Radiation; D013213:Starch / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D010710:Phosphates; D013213:Starch; D000688:Amylose