Lipid composition and deposition during grain filling in intact barley ( Hordeum vulgare) mutant grains as studied by 1H HR MAS NMR

Abstract

Conventional barley has an excellent nutritional value, but a lower content of lipids than oat. Nevertheless, barley lipids deserve a focused interest due to their fatty acid composition and their vitamin E composition. In this study, 1H HR MAS NMR was used to monitor the deposition of lipids during grain filling of conventional barley, and of two barley endosperm mutants with increased lipid content. The lipids in the mutants are primarily synthesized between days 9 and 13, whereas the lipid biosynthesis in the conventional barley took place ten days later. GC analysis on barley flour lipids showed that the mutants and the control exhibit comparable relative levels of the major fatty acids: C16:0, C18:1 and C18:2 despite the higher content of lipids in the mutants. Differences in the minor fatty acid composition between control and mutants were also observed. The degree of unsaturation was found to be increasing during grain filling for both conventional barley and the two mutants.