Phospholipid and fatty acid composition of Bulgarian nut oils

Abstract

The phospholipid and fatty acid composition of three Bulgarian nut oils were investigated. Phospholipids were separated by Folch′s method and two-directional thin-layer chromatography. Their content was determined spectrophotometrically. Phospholipids were present at levels of 0.8% in almond oil, 2.8% in hazelnut oil, and 0.9% in walnut oil. Phosphatidylcholine (18—50%), phosphatidylinositol (18—45%), and phosphatidylethanolamine (8—16%) were found to be the major components. Small amounts of phosphatidylserine, phosphatidic acids, phosphatidylglycerols, lysophosphatidylcholine, and lysophosphatidylethanolamine were also detected. The fatty acid composition of glyceride oils and of the four main phospholipids, namely phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidic acids was identified by capillary gas chromatography of their methyl esters. The predominant fatty acid present in almond and hazelnut oils was linoleic (83.2% and 80.8%, respectively). Oleic acid (18.7%), linoleic acid (48.5%), and linolenic acid (15.8%) were the major components in walnut oil. Higher quantities of saturated fatty acids (27.8—81.2%) were found to be in the phospholipids than in the corresponding oils (9.5—16.7%).