Sea buckthorn (Hippophaë rhamnoides L.) seed oil and pulp oil contain large amounts of unsaturated fatty acids, including the omega-7 fatty acids vaccenic acid (18:1n–7) and palmitoleic acid (16:1n–7). The oils are largely made up of triacylglycerols (TAG). There is evidence suggesting positive effects of the pulp oil on atopic dermatitis.

The aim of this work is to study the biosynthesis of TAGs in developing seeds of sea buckthorn. We target the problem by studying the expression of genes encoding enzymes in the TAG synthesis pathway in a time series collected during two years from two experiments grown in two locations within Finland (south, Turku: 60° N and north, Kittilä: 68° N). Two cultivars (Tytti and Terhi) are included. The study is conducted using quantitative PCR for the genes of interest.

The experimental part of the work is still ongoing. Our first results show the expression levels of different enzyme genes for a period of 12 weeks from early berry development until ripe berries. The expression of several genes changed significantly during the growing season. The most notable increases during seed development were detected in the expression of the genes for Δ⁹-desaturase and diacylglycerol acyltransferase (DGAT) in both of the studied cultivars. These results are being complemented with analysis of fatty acid and TAG composition at the same time points using gas chromatography (GC) and high performance liquid chromatography (HPLC).