What oil for which vitamin?

The absorption efficiency of fat-soluble vitamins (and other lipophilic compounds present in fat) depends on many physicochemical and biological factors. The type of food is a particularly important factor, releasing these compounds more or less easily during digestion, making them more or less absorbable. In order to study this release, a microfluidic chip was developed to monitor in real time the digestion of oil drops containing a fat-soluble vitamin, beta-carotene or vitamin A.

This lab-on-a-chip makes it possible to generate and immobilize these oil drops, then to digest them under a continuous flow of different digestive fluids (buccal, gastric, then intestinal). Oil digestion and vitamin release are then monitored in real time by confocal fluorescence microscopy. The results show that the release of fat-soluble vitamins during digestion is dependent on the oil used, with the final release always reaching a high value. These release rates may partly account for the large effect of the type of fat consumed on the absorption of fat-soluble vitamins, and this provides hope that their absorption efficiency can be controlled by adjusting the type of fat consumed.

After this development phase, this microfluidic chip can now be used as a screening tool for many lipophilic compounds in our diet, in order to better understand their behavior during digestion.

This work was carried out within the framework of H.T. Nguyen's thesis funded by INRA and the Pays de la Loire Region.