Structural and Thermodynamic Characteristics of Starches from Near-Isogenic and Substituted Wheat Lines

The results of studies of the morphology, thermodynamic, and physicochemical properties of starches extracted from grains of soft wheat lines carrying recombinant regions in chromosomes 2A and 7D and the foreign chromosome 4Th of wheatgrass containing genes that control the synthesis of anthocyanin compounds in wheat grain are presented. The presence of recombinant regions in the genome of the studied lines is shown to promote the formation of starch granules of a more regular rounded shape compared to starch from the maternal wheat line Saratovskaya 29 and contributes to an increase of the fraction of larger granules (A-type granules). It is found that the polymorphic structure in all the studied starches does not change and is characterized by the A-type. The thermodynamic parameters of amylopectin melting in wheat starches carrying recombinant chromosome regions and foreign wheatgrass chromosomes have increased compared to the corresponding parameters for starch from the Saratovskaya 29 maternal line, which is accompanied by the formation of a greater number of structurally ordered structures. Recombinant regions in chromosomes have caused an increase in the complex dynamic elastic modulus of starch gel compared to starch gel from maternal wheat. Aqueous gels from wheat starches carrying recombinant regions and foreign wheatgrass chromosomes are characterized by different rates of chemical exchange of water protons when interacting with hydroxyl protons in starch gels.