Effect of route of administration and carrier on bioavailability and kinetics of astaxanthin in Atlantic salmon Salmo salar L.

This study examined astaxanthin bioavailability and kinetics in adult Atlantic salmon Salmo salar L., following two different routes of astaxanthin administration (oral vs. intraperitoneal (i.p.) injection) using two different carriers of the pigment (gelatin vs. sesame oil). The dorsal aorta of adult Atlantic salmon (mean initial weight 950 g) was cannulated. The fish received a single dose of astaxanthin (572 mug kg(-1)) in sesame oil or (514 mug kg(-1)) in gelatin via the oral or i.p. route, Plasma was sampled regularly up to 72 h post oral administration and up to 510 h post i.p. injection. The astaxanthin concentration-time curves from plasma were best fit to a one-compartment pharmacokinetic model for each of the four treatments. The gelatin carrier resulted in higher availability of astaxanthin compared to the sesame oil carrier. The bioavailability for astaxanthin in sesame oil was only 38.7% of that in gelatin by i.p. injection, and only 53.5% of that in gelatin by oral administration. Higher availability of astaxanthin was observed when i.p. injection was used compared to oral administration. The bioavailability for astaxanthin administered orally was only 12% of that by i.p. injection in sesame oil, and only 8.7% of that by i.p. injection in gelatin.