Sesamin as a potential modulator of fatty acid composition in common carp (Cyprinus carpio)

Sesamin enhances the DHA content of tissue lipids in salmonid fish. We have examined whether this effect also occurs in common carp (Cyprinus carpio). Two-year-old common carps were fed a diet containing 5.8 g sesamin kg-1 feed for 69 days. No significant differences were found in the fish weight, specific growth rate, food conversion ratio and lipid content in white muscle. The experimental diet with sesamin increased the percentage of 18:3 n-3 and decreased 18:4 n-3, 22:5 n-3, 22:6 n-3 as well as the desaturation index reflecting the ratio of n-3 long-chain polyunsaturated fatty acids/18:3 n-3 in the triacylglycerol fraction. Sesamin increased the total cytochrome P450 content in hepatopancreatic microsomes as well as 7-ethoxyresorufin O-deethylase (EROD) activity. However, a detailed microarray analysis using 26K gene probes failed to establish any significant pattern of transcriptional response, including lipid biosynthetic genes. Together, these results indicate that under conditions of our study, sesamin was ineffective in the common carp as a means of achieving the changes in the tissue lipid composition as were seen in salmonids.