Isolation and characterization of Boso fish (Oxyeleotris marmorata) oil and their recovery using enzymatic reaction

Oxyeleotris marmorata (Boso) fish is abundant and widespread in West Java Sea area, primarily in Indramayu. This study was aimed to improve the extraction method of essential fatty acids from Boso fish oil, so it would increase the economic value and the benefits of Boso fish. The extraction of fish oil was carried out by n-hexane for 2, 4, 6, 8, 10 and 12 hours. Fish oil was hydrolyzed by a commercial lipase enzyme at various concentration for 48 hours. The fish oil products were analyzed for acid level, acid value and saponification value. Fatty acid contents of fish oil with and without hydrolysis with lipase were determined by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrophotometry (GC-MS) methods. GC-MS results show that fish oil without lipase hydrolysis contained 6.31% omega-6 and 12.31% omega-9, while fish oil hydrolyzed with lipase contained 10.76% omega-6 and 13.84% omega-9. The optimum methyl linolenic acid concentration of 8276.6 ppm was obtained with 9 units lipase concentration, whereas the optimum EPA (eicosapentaenoic acid) concentration of 3937.6 ppm was obtained with 6 units lipase concentration. Enzymatic reactions using lipase can increase the level of omega-3, omega-6 and omega-9 from Boso fish oil.