Abstract:

The fatty acid composition and the contents of octadecadienoic acid in corn embryo oil were determined by using gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC), respectively. The corn embryo oil was extracted by soxhlet extraction, then the fatty oil obtained was esterified by sodium hydroxide-methanol. After purification, the methylated fatty acids were subjected to GC-MS analysis. Totally 8 fatty acids were identified in the corn embryo oil, and 74.94% fatty acids were unsaturated fatty acids. Moreover, the unsaturated fatty acids consisted of octadecadienoic acid (46.33%) and the octadecenoic acid (28.01%). In the following, the content of the octadecadienoic acid in corn embryo oil was determinated by HPLC. The column was Kromasil C18. The mobile phase consisted of iso-propyl alcohol and acetonitrile (35:65). The column temperature was 25 ℃, and detected at 205 nm. The regression equation obtained was y = 1×106x +0.7×106, r =0.9999. The coefficient of variation was less than 1.35%, and the recovery of the method was 98.8%－109.1%. The result indicates that the method is simple , accurate and feasible for determination of octadecadienoic acid in corn embryo oil.

Key words: corn embryo oil, fatty acid, GC-MS, HPLC, octadecadienoic acid