Biocatalytic transesterification of salmon oil in ionic liquid media to obtain concentrates of omega-3 polyunsaturated fatty acids

Abstract

In this study, a biphasic system combining oil and ionic liquid was utilized for lipase-catalyzed transesterification of salmon oil and alcohol to concentrate n-3 PUFAs, notably EPA and DHA. Various process variables, such as enzyme type, quantity, alcohol chain length, temperature, reactant proportions, and ionic liquid selection, were systematically assessed to optimize the process and enhance the yield of these valuable fatty acids. It was found that the Novozym 435 and Lipolase 100L Type EX emerged as the most effective enzymes. The impact of varying alcohol chain lengths (C1–C8) was examined, revealing that the Novozym 435 enzyme displayed its peak synthetic activity with 2-propanol. The results revealed a substantial increase in the overall activity during the transesterification reaction when employing ILs featuring hydrophobic cations and anions with low nucleophilicity. Specifically, the [omim⁺][NTf₂⁻] ionic liquid exhibited the highest level of activity. This research holds promise for more efficiently and sustainably obtaining concentrated n-3 PUFAs from fish oil while reducing environmental impact relative to other existing concentration processes.