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 contents 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 S 2 U, SU 2 , and U 3 , 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), differed from each other in the intensity of degradation. For Land Le-TAGs, initial and final concentrations were similar, while initial concentrations of Stand 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 Stand O-TAGs ranked below them in this respect.

Stage‐specific metabolization of triacylglycerols during seed germination of Sacha Inchi (Plukenetia volubilis L.)

“…The fresh weight of the cotyledons increased rapidly after 3 DAI, whereas the dry matter showed a prominent decline during the same period (data not shown). Previously, closely associated findings were reported during the seed germination of cotton, buckthorn and linseed . In addition, steady rates of cotyledon reserves were observed during the seed germination of Sacha Inchi.…”

“…10 The consumption of the TAG types at different rates during seed germination was a noted phenomenon in several oil seeds, with varying rates depending on the nature of the seeds. 4 In addition, the occurrence of an initial lag period in the process of TAG mobilization in germinating Sacha Inchi seeds was also observed in several other plant species. 11 At present, it is suggested that this phenomenon can be induced by several causes.…”

“…The possible reason for such an action could be the effective activation of the enzyme esterases and hydrolases on MAG, which aid in the degradation of the lipid components, particularly in degrading the DAG and MAG . The consumption of the TAG types at different rates during seed germination was a noted phenomenon in several oil seeds, with varying rates depending on the nature of the seeds . In addition, the occurrence of an initial lag period in the process of TAG mobilization in germinating Sacha Inchi seeds was also observed in several other plant species .…”

The Enigmatic Aliphatic Acetogenins and Their Correlations With Lipids During Seed Germination and Leaf Development of Avocado (Persea americana Mill.)

“…During post-germination, TAGs were reduced, and the PL pool was increased in cotyledons, while EA maintained the same pool of lipids, prevailing PLs, suggesting membrane synthesis. Similar tendencies were reported in seaberry ( Sea buckthorn) , which fruit contains a considerable portion of oil in both mesocarp and seed and mobilizes TAGs and other glycerolipids from cotyledons during post-germination ( Pchelkin et al, 2009 ).…”

“…Interestingly, this is the time when the seeds showed a root protrusion in our samples. Storage tissues, such as cotyledons, generally start oil mobilization after root protrusion in oilseeds ( Rosental et al, 2014 ), sea buckthorn ( Pchelkin et al, 2009 ), and soybean ( Yoshida, 1984 ). Such changes in oil profiles have also been reported in the starchy Oryza seeds as protrusion occurs ( Kim et al, 2012 ).…”