Abstract:

Lipids in the dorsal muscle of Japanese seabass Lateolabrax japonicus grown in seawater and freshwater fortified with the same feed were extracted by reflux extraction with “Folch” solvent, esterified with KOH-BF3 method and analyzed by gas chromatography. The results indicated that an obvious difference in fatty acid profile was observed between the muscles of Japanese sea basses grown in seawater and freshwater. The muscle of Japanese seabass from seawater exhibited higher contents of monounsaturated fatty acids (MUFA), n-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acids (EPA, C20:5 n-3) and docosahexaenoic acids (DHA, C22:6 n-3), and lower levels of saturated fatty acids (SFA), n-6 PUFA and arachidonic acids (AA, C20:4 n-6). The ratios of n-6/n-3 fatty acids in the muscles of seawater and freshwater sea basses were 0.27 and 0.42, respectively. both significantly lower than maximum safety standard (4.0) recommended by the UK Department of Health.

Key words: Japanese sea bass Lateolabrax japonicus, fatty acids, seawater, freshwater