Carotenoid Composition and Two New 4-ketolutein Isomers in the Integuments of the Red Tilefish Branchiostegus japonicus

Abstract

Carotenoids in the integuments of the red tileflsh Branchiostegus japonicus were investigated. Two new keto carotenoids, 4-ketolutein D [(3S, 3'S, 6'S)-3, 3'-dihydroxy-β, ε-caroten-4-one] and 4-ketolutein F [(3S, 3'R, 6'S)-3, 3'-dihydroxy-β, e-caroten-4-one] have been isolated along with the 19 known carotenoids. Astaxanthins (35.8% of the total carotenoid) and tunaxanthins (34.5%) were found to be major components. However tilefishxanthins I, II, III, and IV have not been found in our analysis.