Optimization of Lipase Mediated Enrichment of n-3 PUFA Glycerides in Indian Sardine Oil

Indian Sardine oil is a rich source of n-3 polyunsaturated fatty acids (n-3 PUFA) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which exists in the form of glycerides. The current work aims to optimize a process to enhance n-3 PUFA esters in the refined sardine oil by optimizing the enzymatic hydrolysis of glycerides having saturated fatty acid esters, using Pseudomonas cepacia lipase (PCL). Degree of hydrolysis (DOH) of PCL dissolved in solvent (polypropylene glycol) in the presence of surfactants like tween 80 and SDS was observed to be the highest at 40°C, 4 mg/mL enzyme load, surfactant to enzyme ratio of 2:1 (v/v), oil to water ratio of 1:1 (w/w), hydrolyzed for 15 minutes. After hydrolysis, oil was deacidified using methanolic extraction. Upon analysis of oil by using Gas Chromatography with FID, an increase in n-3 PUFA content from 17.91% (w/w) to 22.63% (w/w) was evidenced. RP-HPLC equipped with ELSD showed that most of the fatty acids exist in the form of monoglycerides.