Polysaccharide formulation for improvement of racemic vitamin E bioavailability.

The relative bioavailability of polysaccharide--racemic vitamin E preparation in comparison with a commercial product was assessed in a kinetic study of plasma alpha-tocopherol in rabbits. Six male rabbits were used in a cross-over design. Alpha-Tocopherol levels were determined by the fluorometric method. A secondary peak in alpha-Tocopherol plasma concentration--time profiles was observed in connection with enterohepatic circulation of vitamin E. A simple one-compartment pharmacokinetic model was proposed to explain enterohepatic circulation of alpha-tocopherol in rabbits. On the basis of the results obtained, it is apparent that polysaccharide--vitamin E preparation achieved a higher rate and extent of absorption. The total AUC of experimental preparation was 1.78-fold greater than that of a commercial capsule preparation, suggesting an increase of bioavailability by 78%.