Plasma responses in human subjects after ingestions of multiple doses of natural α-cryptoxanthin: a pilot study

Abstract

Xanthophylls have attracted a lot of interest since their health benefits were documented. Unfortunately, studying their intestinal absorption is often affected by high baseline levels present in the fasting plasma. As α-cryptoxanthin is rarely found in the traditional European diet, its concentration in human plasma is extremely low. A pilot human intervention study was designed using α-cryptoxanthin for the first time as a marker xanthophyll in a minimally formulated cellulose-based supplement. α-Cryptoxanthin was administered in gelatin soft-gel capsules in multiple doses of 156μg/d to three male volunteers (age 27·3 (sd 4·7) years; BMI 21·6 (sd 0·3) kg/m 2 ) for 16d after a 2-week carotenoid depletion period. Fasting blood samples were taken before the intervention and after 3, 6, 9, 13 and 16d. Plasma HPLC analyses allowed for determination of the concentration; liquid chromatography–MS in the single ion monitoring mode was used to confirm peak assignment. The concentrations of α-cryptoxanthin increased significantly after only 3d of supplementation. The concentration-time plots showed a characteristic shape with a first maximum after day 6, a decline until day 9 and a gradual second rise until the end of the study. Standardisation of plasma α-cryptoxanthin concentrations to triacylglycerol or total cholesterol did not influence the characteristics. The maximum concentrations reached at the end of the intervention period ranged from 0·077 to 0·160μmol/l. These results suggest a high intestinal absorption and an enrichment of α-cryptoxanthin in the plasma even from a minimally formulated cellulose-based supplement.