Isomerization of lycopene in the gastric milieu

There is considerable interest in the bioavailability of carotenoids from t he diet and their bioactivity in vivo. Little is known, however, of the pre absorption events in the gastric lumen on the breakdown or isomerisation of dietary carotenoids, In this study the effects of the acidic environment f ound in the gastric milieu on lycopene have keen investigated. The results show that under these conditions all-trans-lycopene is isomerised to cis-is omers, which may be implicated in enhanced absorption from the small intest ine. Furthermore the pH, as well as the food matrix, seems to have an influ ence on the level of isomerisation of this carotenoid. (C) 2001 Academic Pr ess.