Wax esters: major marine metabolic energy sources

The importance of polyunsaturated wax esters as metabolic reserves in marine copepods has been recognized by Lee et al. (1970). These major zoo- plankton of the world's oceans convert the highly unsaturated triglycerides ofdiatom and dinoflagellate algae on which they graze into wax esters comprised of polyunsaturated fatty alcohols and polyunsaturated fatty acids. Metabolic-turnover experiments have revealed that the animals first utilized the triglyceride components of their stored lipids and then more slowly metabolized their wax ester reserves. Although all copepods store wax ester, those of temperate and polar waters have adapted to their environment and long unproductive winters by accumulating up to 75% of their body weight as wax ester. In warm tropical waters the continuity of the food supply makes long-term energy supplies unnecessary and wax ester storage is minimal.