Comprehensive Analysis of Fatty Acid and Oxylipin Patterns in n3-PUFA Supplements

Supplementing long-chain omega-3 polyunsaturated fatty acids (n3-PUFA) improves health. We characterized thepattern of total and non-esterified oxylipins and fatty acids in n3 supplements made offish, krill, or micro-algae oil by LC-MS. Allsupplements contained the declared amount of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA); however, theircontent per capsule and the concentration of other fatty acids varied strongly. Krill oil contained the highest total n3 oxylipinconcentration (6000 nmol/g) and the highest degree of oxidation (EPA 0.7%; DHA 1.3%), while micro-algae oil (Schizochytriumsp.) showed the lowest oxidation (<0.09%). These oils contain specifically high amounts of the terminal hydroxylation product ofEPA (20-HEPE, 300 nmol/g) and DHA (22-HDHA, 200 nmol/g), which can serve as an authenticity marker for micro-algae oil.Refined micro-algae andfish oil were characterized by NEFA levels of <= 0.1%. Overall, the oxylipin and fatty acid pattern allowsgaining new insights into the origin and quality of n3-PUFA oils in supplements

Automated summary

This study analyzed n3 supplements made from fish oil, krill oil, and micro-algae oil using LC-MS. The results showed significant variations in total oxylipins and non-esterified fatty acid content among the supplements, with krill oil having the highest concentration and micro-algae oil having the lowest. The study also identified terminal hydroxylation products as authenticity markers for micro-algae oil. Refined micro-algae and fish oil had low levels of non-esterified fatty acids.