Triacylglycerol metabolization during germination of sea buckthorn seeds.

Abstract

Dark germination of sea buckthorn seeds was characterized by an initial 3-day-long lag-period, when the con- tents of triacylglycerols (TAGs) and total acyl-containing lipids (ACLs) remained nearly the same due to retardation in the lipid metabolization. Subsequently, TAG content decreased rapidly, and by the 10th day of germination, it did not exceed 5% of total lipids. In this process, total saturated (S) and total unsaturated fatty acids (U), as well as various TAG types such as S2U, SU2, and U3, were consumed at nearly similar relative rates. At the same time, separate TAG groups, which included one of the individual fatty acids, such as palmitic (P), stearic (St), oleic (O), linoleic (L), or linolenic (Le), dif- fered from each other in the intensity of degradation. For L- and Le-TAGs, initial and final concentrations were similar, while initial concentrations of St- and O-TAGs by the 10th day of germination increased 2.3- and 1.5-fold, respectively, and as regards P-TAGs, this value decreased 3.5-fold. Thus, P-TAGs considerably exceeded other TAG groups in their consumption rate in seedlings, while St- and O-TAGs ranked below them in this respect.