Date of Graduation
Davis College of Agriculture, Natural Resources and Design
Human Nutrion and Foods
Janet C Tou
Objective. 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 (o-3 PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The o-3 PUFAs in krill are mainly associated with phospholipids, which have been proposed to result in high incorporation of o-3 PUFAs into tissues and to be stable against oxidation. The study objective was to determine bioavailability, tissue deposition, peroxidation, and metabolism of o-3 PUFAs in rats fed KPC.;Methods. Young female Sprague-Dawley rats (n=10/group) were fed ad libitum isocaloric diets with either 10% freeze-dried KPC containing 0.9% krill oil with 4.4% corn oil (KO + CO) or 10% casein with 5.3% corn oil (C+CO) for 4 weeks. Bioavailability was measured by determining apparent digestibility of dietary lipid during the final week of the study. Fatty acid compositions of diets, various tissues, and feces were analyzed by gas chromatography. Lipid peroxidation was determined by TBARS. Total antioxidant capacity and urinary eicosanoid metabolites were determined by enzyme immunoassay.;Results. Rats fed KO + CO had a low apparent digestibility (%) of AA (22.75+/-6.45), moderate apparent digestibility (%) of EPA (70.12+/-3.52) and high apparent digestibility (%) of DHA (93.42+/-1.64). The 0.9% KO from KPC increased (P<0.01) EPA and DHA content in adipose and liver tissue while decreasing (P<0.01) the o-6 PUFA, arachidonic acid. DHA was increased (P=0.003) in the brain of rats fed KO + CO. There was no significant difference in total antioxidant capacity or lipid peroxidation between diets. Feeding the KO + CO diet decreased (P=0.009) urinary PGE2 metabolites. There was a tendency (P=0.054) for decreased urinary 11-dehydro TXB2 in rats fed KO + CO.;Conclusion. The 0.9% KO from KPC provided by the diet was able to increase o-3 PUFAs and decrease AA tissue accretion resulting in reduced pro-inflammatory eicosanoid metabolites. The results suggest that KPC from krill provides a healthy and sustainable alternative to fish or fish oil supplement.
Bridges, Kayla Marie, "The omega-3 fatty acid content of krill protein concentrate influences bioavailability, tissue deposition, peroxidation, and metabolism in young rats" (2009). Graduate Theses, Dissertations, and Problem Reports. 4443.