title: Starch structure in developing barley endosperm.
abstract: Barley spikes of the cultivars/breeding lines Gustav, Karmosé and SLU 7 were harvested at 9, 12 and 24 days after flowering in order to study starch structure in developing barley endosperm. Kernel dry weight, starch content and amylose content increased during development. Structural analysis was performed on whole starch and included the chain-length distribution of the whole starches and their β-limit dextrins. Karmosé, possessing the amo1 mutation, had higher amylose content and a lower proportion of long chains (DP ≥38) in the amylopectin component than SLU 7 and Gustav. Structural differences during endosperm development were seen as a decrease in molar proportion of chains of DP 22-37 in whole starch. In β-limit dextrins, the proportion of Bfp-chains (DP 4-7) increased and the proportion of BSmajor-chains (DP 15-27) decreased during development, suggesting more frequent activity of starch branching enzymes at later stages of maturation, resulting in amylopectin with denser structure.
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Källman
authors.affiliation: Food Science Department, University of Guelph, Guelph, ON N1G 2W1, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Bertoft
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden.
authors.forename: Kristine
authors.initials: K
authors.lastname: Koch
authors.affiliation: Department of Plant Biology and Forest Genetics, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, P.O. Box 7080, S-750 07 Uppsala, Sweden.
authors.forename: Chuanxin
authors.initials: C
authors.lastname: Sun
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Åman
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, P.O. Box 7051, S-750 07 Uppsala, Sweden. Electronic address: Roger.Andersson@slu.se.
authors.forename: Roger
authors.initials: R
authors.lastname: Andersson
mesh_terms: D015061:1,4-alpha-Glucan Branching Enzyme / Q000737:chemistry; D000688:Amylose / Q000737:chemistry; D001947:Breeding; D056625:Endosperm / Q000737:chemistry*; D001467:Hordeum / Q000737:chemistry* / Q000235:genetics; D009154:Mutation; D013213:Starch / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D013213:Starch; D000688:Amylose; D015061:1,4-alpha-Glucan Branching Enzyme
keywords: Amylopectin structure; Barley; Endosperm development; Starch