Comparative characteristics of the lipidome of Cycas revoluta and C. rumphii (Cycadaceae)

A targeted lipidomics analysis of four classes of membrane glycerolipids was carried out in two species of Cycadaceae from the genus Cycas – C. revoluta and C. rumphii. The analysis of the molecular diversity of the main phospholipids, which are the components of extra-chloroplast membranes, has revealed archaic features, including a high level of molecular species containing C18:1 fatty acids (typical of Ginkgo biloba), increased relative content of molecular species with odd fatty acids C17:0 and C19:0 (typical of non-seed plants). At the same time, the analysis of the molecular diversity of the glycolipids which are the components of chloroplast membranes, did not find significant differences from most seed plants, which indicates a higher conservation of lipids of a photosynthetic apparatus. The identified features of the molecular composition of glycerolipids of two species of Cycas indicate the prospectiveness of using lipidomics for taxonomic and phylogenetic studies, with the data on the molecular composition of phosphatidylcholines, for which the greatest heterogeneity and species-specificity was demonstrated, deserving the most attention.