Table 1.
Parameters of tocopherol absorption as a function of micellar tocopherol concentrations in differentiated Caco-2 TC-7 cell monolayers.
Vitamin E species | Apparent Qmax (nmole tocopherol absorbed/mg of protein) | Apparent K (μM) |
---|---|---|
RRR-α-T | 7.5 ± 0.6 | 84.3 ± 9.9 |
RRR-γ-T | 6.5 ± 0.5 | 83.9 ± 11.5 |
DL-α-T | 5.6 ± 0.7 | 88.3 ± 15.2 |
Tocopherol uptake was measured at 37°C after apical micellar tocopherol delivery in increasing concentrations. Incubation time was 15 min. Best fitting curves were hyperbolic curves y = ax/(b+x). Qmax represents the maximal amount of tocopherol absorbed, and K represents the concentration of micellar tocopherol required to reach Qmax/2. Data are means ± SD of 3 assays.