Variation in polar lipid composition among near-isogenic wheat lines possessing different puroindoline haplotypes

• Published in: Journal of cereal science 2010, Vol.51 (1), p.66-72
• Main Authors: Finnie, S.M., Jeannotte, R., Morris, C.F., Faubion, J.M.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Cereal and baking product industries; Electrospray ionization tandem mass spectrometry; Food industries; Fundamental and applied biological sciences. Psychology; haplotypes; line differences; lines; lipid composition; lipids; plant proteins; Polar lipids; Puroindoline; puroindolines; Triticum aestivum; Wheat; wheat flour; wheat starch
• ISSN: 0733-5210; 1095-9963
• DOI: 10.1016/j.jcs.2009.09.006

The exact mechanism underlying wheat ( Triticum aestivum L.) kernel hardness is unknown. Similar to puroindoline proteins, polar lipids are present on the surface of starch granules. The objective of this research was to determine the specific polar lipid species present on the surface of wheat starch from near-isogenic wheat lines that have different puroindoline haplotypes and endosperm hardness. Four near-isogenic wheat lines were used in this study, all derived from the soft cultivar Alpowa. Direct infusion tandem mass spectrometry was used to identify the lipid species in whole-meal, flour and starch samples. Endosperm hardness had no significant effect on the polar lipid contents in wheat whole-meal, a slight influence on the polar lipid contents of the flour fractions and a significant influence on the polar lipid composition of the polar lipids located on the surface of wheat starch. The greatest quantities of polar lipids on the starch-surface occurred when both puroindoline proteins were present in their wild-type form. Starch-surface polar lipid content dramatically decreased when one of the puroindoline proteins was null or if pin-B was in the mutated form. The least amount of polar lipids was present when pin-B was in its mutated form and pin-A was in its wild-type form.