Changes in the fatty acids of neutral and polar lipids of Silurus glanis and Barbus capito capito during an annual cycle

Seasonal changes in the fatty acid composition of neutral (NL) and polar lipid (PL) fractions of immature Wels (Silurus glanis) and bulatmai barbel (Barbus capito capito) were investigated. the most abundant saturated, monounsaturated, and n-3 and n-6 polyunsaturated fatty acids (PUFA) for both fractions were palmitic, oleic, docosahexaenoic (DHA), and linoleic acid, respectively. the maximum n-3/n-6 PUFA ratio and eicosapentaenoic acid (EPA)+DHA content of the NL and PL fractions were found in the hot and cold seasons, respectively. the high n-3/n-6 ratio and the high EPA+DHA content of the NL fraction might be influenced by the composition of ingested food and that high amount in the PL fraction can be explained by the fact that fish acclimatize to the cold. Finally, these species are recommended for human consumption throughout the year, especially in winter due to the high n-3/n-6 ratio and the EPA+DHA content of the PL fraction during this season. Key words: seasonal changes, fatty acid, neutral lipid, polar lipid, Silurus glanis, Barbus capito capito, n-3/n-6 PUFA, EPA+DHA