Adaptation of Litoral Halophytes to the Conditions of the Coastal Territories of the White Sea: Involvement of Fatty Acid Composition of Lipids

The authors studied the composition of fatty acids (FAs) in four species of dominant obligate halophytes— Triglochin maritima , Plantago maritima , Tripolium pannonicum subsp. tripolium , and Lysimachia maritima —growing in different flood conditions in the littoral zone of the White Sea. It was found that the content of total FA varied from 13 to 22 mg/g a.d.w. with maximum values in L. maritima and minimal in P. maritima . All species have high values of UFA content (74–77%), double bond index (1.6–1.8), and a significant contribution of triene FAs (45–55%). A high diversity of long-chain FAs (C20–24) was established: 14 FAs. This analysis showed the similarity of all halophytes in the main parameters of FA composition and the high functional activity of halophyte membrane systems. Two clusters of species with different adaptive responses have been identified: the first includes P. maritima, Triglochin maritima and Tripolium pannonicum and the second includes L. maritima . A comparison of data for two clusters showed that there are FAs that are involved in the adaptation of all types of C18:3(n-3), C16:0, C18:2(n-6), and FAs that differ among clusters. For species of the first cluster, 1 FA is C20:4(n-4), and, for the second cluster, 4 FAs are C18:1(n-9), C18:3(n-4), C20:1(n-9), and C22:0. The revealed differences may be associated with different ways of adaptation of halophytes of the two clusters to littoral conditions.