2008 Volume 19 Issue 1 Pages 13-17
We investigated the reductive metabolism of Carophyll-yellow, which is the cold-water soluble beadlets of the β-apo-8'-carotenoic acid ethyl ester, to retinol.
Thirty male rats (STD Wistar, 3-weeks old) were Fed a Vitamin A deficient diet (AIN-76) for 35 days prior to experiment. They were than divided into 5 groups, 2 of which were used as the control group. Each of the remaining 3 groups was fed a diet containing β-carotene, Carophyll-yellow, or retinyl acetate for 8 days, and the changes in there body weights during the experiment period were investigated. After a one-day fast, the concentrations of retinol, 3,4-didehydroretinol and retinyl ester in the plasma and liver were measured.
The increased body weight of the Carophyll-yellow group was 1.4 times that of the control group. In the Carophyll-yellow group, the retinol content was 1.9 nmol/ml in the plasma and 1.9 nmol/ml in the liver, and that of 3,4-didehydroretinol was 1.8 nmol/ml in the plasma and 1.6 nmol/ml in the liver.
Based on these results, it is apparent that the 3,4-didehydro-β- apo-8'- carotenoic acid ethyl ester in Carophyll- yellow is converted into retinol by the reductive metabolism via 3,4-didehydroretinol.
