Fatty acid composition of pinaceae as taxonomic markers

Abstract

Following our previous review on Pinus spp. seed fatty acid (FA) compositions, we recapitulate here the seed FA compositions of Larix (larch), Picea (spruce), and Pseudotsuga (Douglas fir) spp. Numerous seed FA compositions not described earlier are included. Approximately 40% of all Picea taxa and one-third of Larix taxa have been analyzed so far for their seed FA compositions. Qualitatively, the seed FA compositions in the three genera studied here are the same as in Pinus spp., including in particular the same delta5-olefinic acids. However, they display a considerably lower variability in Larix and Picea spp. than in Pinus spp. An assessment of geographical variations in the seed FA composition of P. abies was made, and intraspecific dissimilarities in this species were found to be of considerably smaller amplitude than interspecific dissimilarities among other Picea species. This observation supports the use of seed FA compositions as chemotaxonomic markers, as they practically do not depend on edaphic or climatic conditions. This also shows that Picea spp. are coherently united as a group by their seed FA compositions. This also holds for Larix spp. Despite a close resemblance between Picea and Larix spp. seed FA compositions, principal component analysis indicates that the minor differences in seed FA compositions between the two genera are sufficient to allow a clear-cut individualization of the two genera. In both cases, the main FA is linoleic acid (slightly less than one-half of total FA), followed by pinolenic (5,9,12-18:3) and oleic acids. A maximum of 34% of total delta5-olefinic acids is reached in L. sibirica seeds, which appears to be the highest value found in Pinaceae seed FA. This apparent limit is discussed in terms of regio- and stereospecific distribution of delta5-olefinic acids in seed triacylglycerols. Regarding the single species of Pseudotsuga analyzed so far (P. menziesii), its seed FA composition is quite distinct from that of the other two genera, and in particular, it contains 1.2% of 14-methylhexadecanoic (anteiso-17:0) acid. In the three genera studied here, as well as in most Pinus spp., the C18 delta5-olefinic acids (5,9-18:2 and 5,9,12-18:3 acids) are present in considerably higher amounts than the C20 delta5-olefinic acids (5,11-20:2 and 5,11,14-20:3 acids).

Structures, practical sources (gymnosperm seeds), gas-liquid chromatographic data (equivalent chain lengths), and mass spectrometric characteristics of all-cis Δ5-olefinic acids

“…On the contrary, they are the rule. This was observed in earlier and more recent systematic studies of gymnosperm leaf [28,29] and seed lipids [30], and for the latter, extended to practically all species analysed so far (approximately 170 species analysed by author Wolff and co-workers [26,27,[31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46]). They also occur in wood [47][48][49][50][51][52] lipids, but the number of species analysed for these tissues is much more limited.…”

“…This profile may be used as a chemometric means for the taxonomy of conifer families and genera [33][34][35][44][45][46], that generally coincide with the same taxa characterised by botanical criteria. Though of apparent academic interest, this feature has practical implications in that it allows prediction of species in which a given category of ∆5-UPIFA is likely to be present, but unfortunately not systematically prediction of its abundance.…”

Overexpression of an Isoprenyl Diphosphate Synthase in Spruce Leads to Unexpected Terpene Diversion Products That Function in Plant Defense

“…The occurrence of phytyl esters is also common in plants, as mentioned above (Csupor, 1970;Liljenberg, 1977;Anderson et al, 1984;Pereira et al, 2002;Gaude et al, 2007), indicating that esterification of prenyl alcohols to fatty acid esters is a widespread phenomenon. The unusual anteiso fatty acid found as a component of these esters, anteisoheptadecanoic acid (14-methylhexadecanoic acid), has also already been reported from other conifers of the Pinaceae (Wolff et al, 1997(Wolff et al, , 2001.…”

Novel fatty acid elongases and their use for the reconstitution of docosahexaenoic acid biosynthesis

“…Expressions were carried out for 4 days at 20ЊC in the presence of exogenously supplied fatty acids of commercial origin (250-500 M). Pinolenic acid (18:3 ⌬5,9,12 ) was part of a fatty acid mixture isolated from Larix decidua seeds (25). For the coexpression of elongases and desaturases, the yeasts were additionally transformed with the ⌬5-desaturase from Phaeodactylum tricornutum (26) and the ⌬4-desaturase from Euglena gracilis (11).…”