Structure of long-chain n-3 PUFA found in fish oil

Long-chain n-3 PUFA are almost exclusively derived from seafood sources and include eicosapentaenoic acid (EPA,20:5n-3), docosapentaenoic acid (DPA,22:5n-3), and docosahexaenoic acid (DHA,22:6n-3). Given the long carbon chains and multiple double bonds, these fatty acids have complex 3-dimensional configurations, very different from the relatively straight chains of most other fatty acids.