Lipid Structure Influences the Digestion and Oxidation Behavior of Docosahexaenoic and Eicosapentaenoic Acids in the Simulated Digestion System

Abstract

<p>Omega-3 fatty acids such as eicosapentaenoic acid (EPA)and docosahexaenoicacid (DHA) are essential for human health but prone to oxidation.While esterification location is known to influence the stabilityof omega-3 in triacylglycerols (TAGs) in oxidation trials, their oxidativebehavior in the gastrointestinal tract is unknown. Synthesized ABA-and AAB-type TAGs containing DHA and EPA were submitted to static <i>in vitro</i> digestion for the first time. Tridocosahexaenoinand DHA as ethyl esters were similarly digested. Digesta were analyzedby gas chromatography, liquid chromatography-mass spectrometry,and nuclear magnetic resonance spectroscopy. Besides the formationof di- and monoacylglycerols, degradation of hydroperoxides was detectedin ABA- and AAB-type TAGs, whereas oxygenated species increased intridocosahexaenoin. Ethyl esters were mainly unaffected. EPA was expectedlyless susceptible to oxidation prior to and during the digestion process,particularly in sn-2. These results are relevantfor the production of tailored omega-3 structures to be used as supplementsor ingredients.<br></p>