Permeation of steryl ferulates through an in vitro intestinal barrier model.

Steryl ferulates (SFs) belong to the bioactive lipids contributing to the health promoting effects of whole grains. However, their intestinal absorption remains unclear. We investigated the permeation of individual SFs using an in vitro intestinal barrier model. An in vitro Caco-2 cell monolayer, mimicking the intestinal barrier, was used to evaluate the permeation of eight SFs from different sources. A method based on ultra-performance LC with high-resolution mass spectrometric detection was developed for their quantification. Although only a negligible amount (< 0.5%) permeated across the Caco-2 cell monolayer, some differences in the permeability coefficients were observed between individual SFs. Permeation mechanism was mainly passive diffusion. This work indicates that the permeation of SFs across the gut is very low. Therefore, cholesterol lowering and antioxidant activity-related health benefits of SFs most likely occur in the gut independently from absorption.