Intestinal absorption of lycopene from different types of oleoresin capsules

After a 2-wk depletion period, 24 volunteers, divided into 3 groups, ingested 5 mg/d lycopene for 4-wk from 5 capsules containing tomato oleoresin or synthetic lycopene. Plasma samples were analyzed on carotenoids using C-18 HPLC with diode array detection. Basal lycopene levels (0.19 to 0.31 mumol/L) in plasma of the 3 groups were in a comparable range (p > 0.05) and significantly decreased after the 2-wk diet low in lycopene to 21 to 52 % of the basal values. Four out of 5 investigated capsules significantly (p < 0.05) enhanced the plasma lycopene levels relative to the depleted state after I wk of supplementation to 0.20 to 0.27 mumol/L. Increasing the surface of lycopene crystals by reducing the particle size was the most effective processing step to enhance intestinal absorption of lycopene. However, presence of tomato oil in oleoresin and partly removal of selective fatty acids affected the intestinal absorption of lycopene, too.