The Effect of Omega‐3 Fatty Acids Derived from Krill Protein Concentrate on Tissue Deposition and Lipid Peroxidation

Krill protein concentrate (KPC) has been determined to be a high quality protein for human consumption with the advantage of being a rich source of the omega‐3 polyunsaturated fatty acids (ω‐3 PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The ω‐3 PUFAs in krill oil are mainly associated with phospholipids, which have been proposed to result in high incorporation of ω‐3 PUFAs into tissues and to be stable against oxidation. The study objective was to determine tissue deposition and oxidative stability of ω‐3 PUFAs in rats fed KPC. Young female Sprague‐Dawley rats (n=10/group) were fed ad libitum isocaloric diets with either 10% freeze‐dried KPC (~8% oil) containing 4.4% corn oil (KPC + CO) or 10% casein containing 5.3% corn oil (C + CO) for 4 weeks. Fatty acid compositions of various tissues were analyzed by gas chromatography. Lipid peroxidation was determined by TBARS and total antioxidant capacity by enzyme immunoassay. The study results showed even at a KPC contribution of 0.9% lipids to the total diet, EPA and DHA content increased (P<0.01) in adipose and liver tissue while decreasing (P<0.01) the ω‐6 PUFA, arachidonic acid. There was no significant difference in brain tissue deposition of ω‐3 PUFAs, total antioxidant capacity, or lipid peroxidation between groups. Based on the study results, ω‐3 PUFAs associated with KPC resulted in tissue incorporation without changing oxidative stability.