Conifer seed oils: Distribution of Δ5 acids between α and β chains by13C nuclear magnetic resonance spectroscopy

Nine seed oils from three different conifer families, already examined by gas chromatography and known to contain diene, triene, and tetraene C18 and C20Δ5 acids, have been reexamined by high‐resolution13C nuclear magnetic resonance spectroscopy. The Δ5 acids are apparent only in the α‐chains. This location is independent of chainlength, double‐bond number, and the species considered and is probably a general factor of conifer seed oils. The spectra confirm the presence of oleic, linoleic, α‐linolenic, and of Δ5 acids and give quantitative information about (total) n‐6, n‐3, and Δ5 acids that is in accord with that obtained by gas chromatography.