Enrichment of lecithin with n-3 fatty acids by acidolysis using immobilized phospholipase A1

A commercial phospholipase A1 (Lecltase® Ultra) was Immobilized by physical adsorption on Duolite®and then used to mediate the incorporation of omega-3 fatty acids into lecithin. Adsorption isotherms showed that 12 h of contact were sufficient to deposit most of the enzyme onto the carrier. A pH of 7 and 50°C were the best conditions for adsorption. Reaction mixtures consisting of lecithin and a saponified fish oil concentrate (78.4 mol % EPA+DPA+DHA) were prepared at molar ratios ranging from 1:2 to 1:10. Typically 2 g of total substrates and 200 mg of enzyme preparation were employed in batch reactor trials. The fastest reaction rates were observed when a substrate mole ratio of 1:8 (lecithin:total fatty acids) was employed. Use of the enzyme preparation dried at pH 8 and reaction temperatures of 50 and 60°C produced the greatest extent of incorporation of the indicated n-3 fatty acids into the phospholipid after 24h of reaction.