Phosphatidylethanolamine, oleic acid and gondoic acid enhance lutein bioavailability: A hybrid static-dynamic-in vivo study.

Lutein has low stability and limited bioaccessibility in infant formulas. By integrating in vitro (static and dynamic) and in vivo digestion models, oleic acid (OA), gondoic acid (GA) and phosphatidylethanolamine (PE) were identified as agents that raise lutein bioaccessibility by 6-13% under static in vitro conditions. During digestion the additives reduced emulsion droplet size (0.3% PE most effective), inhibited lipid-droplet aggregation and enhanced micellar stability. PE additionally accelerated intestinal free fatty acid release. Dynamic digestion gave higher absolute values but identical trends. In neonatal mice, OA, GA and PE increased lutein accumulation in small intestine, liver and eye, with PE the most potent. These findings provide three critical agents and a mechanistic rationale for stable, bioavailable lutein-fortified infant formulas.