Characterization of oil exhibiting high γ-linolenic acid from a genetically transformed canola strain

Abstract

The seed oil from a genetically transformed canola (Brassica napus) containing 43% (w/w) of γ-linolenic acid (G, 18:3n-6), 22% linoleic acid (L, 18:2n-6), and 16% oleic acid (O, 18:1 n-9) was evaluated. In this high γ-linolenic acid canola oil (HGCO), the predominant 18:3n-6-containing triacylglycerol (TG) molecular species were GGL (23%), GLO (20%), and GGG (11%). In the total TG, approximately 75% of the 18:3n-6 was located at the sn-1,3 positions, while only 34% of linoleic acid was at the sn-1,3 positions. The GGL molecular species of HGCO contained approximately equal amounts of GLG and GGL positional isomers, while the GLO molecular species had 95% GOL and 5% GLO isomers. The general characteristics and the tocopherol and phytosterol contents were mostly similar between HGCO and nontransformed canola oil. No detectable amounts of amino acids and nucleotides were observed in the HGCO.