M. Stancheva, A. Merdzhanova

Abstract. The aim of the present study was to determinate the fatty acid composition of two commercially important freshwater fish species – rainbow trout (Oncorhynchus mykiss) and carp (Cyprinus carpio L.) and one Black Sea fish – grey mullet (Mugil cephalus). Lipid extraction was done according to the Bligh and Dyer method. Methyl esters were prepared according to method EN ISO 5508:2000. The fatty acid (FA) composition was analyzed by GC-MS. The total lipid content in rainbow trout was 11.50 g/100g raw weight (r.w.), in carp – 12.74g/100 g r.w. while grey mullet showed a value of 3.80g/100g r.w. In comparison with other groups, the polyunsaturated FA (PUFA) showed the highest level in trout – 43.13 % including ω3 such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids followed by grey mullet –29.1%, whereas the carp presented lowest level – 17.55%. The amounts of total ω6 PUFAs were higher than the total ω3 PUFAs in all analyzed fish samples. A ω3 /ω6 and PUFA/SFA ratios were determined in all three fish species.