Oil from the micro-algae Nannochloropsis oculata contains a significant amount of EPA linked to phospholipids and glycolipids, and no DHA. Krill oil contains EPA and DHA conjugated to phospholipids. The research compares the appearance of fatty acids in blood plasma of healthy humans after consuming a high fat meal followed by either algal oil or krill oil.
Fatty acids derived mainly from the breakfast appeared rapidly in plasma, peaking about 3 hours after consuming the breakfast, and in a pattern that reflected their content in the breakfast. There were time-dependent increases in the concentrations of both EPA and DHA with both algal oil and krill oil. The concentration of EPA was higher with algal oil than with krill oil at several time points. DHA concentration did not differ between oils at any time point. The maximum concentration of EPA was higher with algal oil and both the area under the concentration curve (AUC) and the incremental AUC for EPA were greater with algal oil. There was no difference between oils in the AUC or the incremental AUC for DHA.
Full research here.