Stability of resveratrol esters with caprylic acid during simulated in vitro gastrointestinal digestion

Lipophenols, esterified phenols with fatty acids, have attracted increasing attention because of their better protective effects in lipid-based food matrices from oxidation. However, little is known about their digestion. In this study, the digestive stability of resveratrol (RSV) esters with caprylic acid (RCAPs) in a model gastrointestinal digestion system was evaluated. The results demonstrated that RCAPs were relatively stable without hydrolysis in mouth and gastric phases. However, in the intestinal phase, pancreatic lipase rather than phospholipase A2 could hydrolyze monoester and diesters to free RSV. After 120 min of incubation at 37 °C, 53.68% of monoester and 11.36% of diesters were hydrolyzed. However, no hydrolysis of the triester was noticed. Obviously, the level of hydrolysis of RCAPs was negatively correlated with the degree of substitution. Therefore, it was speculated that RSV in fatty acid ester forms could partially be absorbed by intestinal lumen in the form of free RSV.