title: Structure of building blocks in amylopectins.
abstract: Building blocks represent the smallest, branched units found inside clusters of amylopectins. The building blocks from clusters of 10 different amylopectins, representing a wide variety of plants, were isolated and size-fractionated. The unit chain compositions were then analysed. It was found that the number of chains in building blocks increased in proportion to their size similarly in all samples regardless plant source. The smallest blocks (DP 5-9) consisted of 2 chains and the largest blocks (DP ≥45), of which generally only little existed, possessed ≥10 chains. Generally, the degree of branching increased with building block size, but the organisation of chains inside the blocks was unique for each sample. Nevertheless, compared to other plants, amylopectins from cereals (represented by rye, oats, rice and waxy maize) possessing elevated number of the shortest internal B-chains (DP 3-7), tended to have blocks with a lower ratio of A:B-chains, indicative of a preferred Haworth type of structure as opposed to the Staudinger configuration.
authors.affiliation: Department of Food Science, Swedish University of Agricultural Sciences, PO Box 7051, S-750 07 Uppsala, Sweden.
authors.forename: Eric
authors.initials: E
authors.lastname: Bertoft
authors.forename: Kristine
authors.initials: K
authors.lastname: Koch
authors.forename: Per
authors.initials: P
authors.lastname: Man
mesh_terms: D000687:Amylopectin / Q000737:chemistry*; D002236:Carbohydrate Conformation
chemical_list: D000687:Amylopectin