Metabolism of Carotenoids in the Apple Snail, Pomacea canaliculata

Abstract

Feeding experiments with β,β-carotene, canthaxanthin, (3R,3′R)-zeaxanthin, (3R,3′R,6′R)-lutein and racemic astaxanthin on the apple snail Pomacea canaliculata were investigated. Based on the experimental results, β,β-carotene was oxidatively metabolized, and the resulting principal metabolic product (3S,3′S)-astaxanthin along with other keto carotenoids such as (3S)-3-hydroxy-β-echinenone, canthaxanthin, (3S,3′R)-4-ketozeaxanthin and (3S)-phoenicoxanthin was accumulated in the gonad. Similarly, (3R,3′R,6′R)-lutein was converted into fritschiellaxanthin [(3S,3′R,6′R)-3,3′-dihydroxy-β, ϵ-caroten-4-one]. It was concluded that P. canaliculata had the ability to oxidize the C-3, 4 positions on the β-end group.