FATTY-ACIDS OF THE SEEDS FROM PINE SPECIES OF THE PONDEROSA-BANKSIANAAND HALEPENSIS SECTIONS - THE PECULIAR TAXONOMIC POSITION OF PINUS-PINASTER

The fatty acid compositions of pine seed oils were determined from 11 species of the Banksiana subsection and three species of the Ponderosa subsection. All were collected in North America (United States, Mexic o, and Cuba). These analyses also included the seed oils from the uniq ue European species of the Ponderosa-Banksiana section (Banksiana subs ection), Pinus pinaster, and from three pine species of the Halepensis section, which are related to the Banksiana subsection. Emphasis was placed on their Delta 5-olefinic acid content and profile. Principal-c omponent analysis of fatty acid compositions showed that all North Ame rican species constituted a fairly homogeneous group. However, P. jeff reyi was slightly eccentric, and P. pinaster, a west-Mediterranean spe cies, was completely isolated from the North American group. Other spe cies from the Banksiana and Ponderosa subsections could not be disting uished on the basis of their seed oil fatty acid compositions. With re spect to Delta 5-olefinic acids, the North American species (except fo r P. jeffreyi) had 5,9-18:2, 5,9,12-18:3, 5,11-20:2, and 5,11,14-20:3 acid concentrations in the ranges 1.9 to 3.2, 17.7 to 22.9, 0.2 to 0.4 , and 2.0 to 3.5%, respectively (sum, 22.7-28.5%). Levels of correspon ding acids in P. pinaster were 0.9, 7.9, 0.9, and 7.0%, respectively ( sum, 16.7%). Other differences were observed for linoleic acid (42.6 t o 48.6% vs. 52.2%) and alpha-linolenic acid (0.3 to 0.6% vs. 1.4%). Pi nus pinaster was close to species of the Halepensis section (5,9-18:2, 0.5 to 1.0%; 5,9,12-18:3, 3.1 to 4.4%; 5,11-20:2, 0.4 to 0.5%; 5,11,1 4-20:3, 3.6 to 5.4%; sum, 8.6-11.1%), which were clearly separated fro m the ponderosa-Banksiana section. Among ail pines analyzed, P. pinast er presented the highest level of sciadonic (5,11,14-20:3) acid, a com ponent that has three ethylenic bonds in common with arachidonic and e icosapentaenoic acids.