Caco-2 cells were grown to confluence and differentiated for 3 weeks on filters (upper panel). The microvilli of cells were on the apical side. Monolayer integrity was evaluated by TEER, measured by using a Millicell-ERS voltohmmeter. Caco-2 cell monolayer could be used when TEER value was over 500 Ωcm2 [18]. The Papp (cm/s) values of ferulic acid were calculated as described in the method (lower panel). Data expressed as Papp values (cm/s), Mean ± SD, where n = 4, each with triplicate samples. **p<0.01 compared to ferulic acid alone. |