The Biosynthesis of Astaxanthin-XIII

Abstract

The carotenoids of crab, Portunus trituberculatus, have been separated by absorption chromatography and further characterized by their absorption spectra and their behavior on the column. In some cases, reactions for specific functional groups were performed. The existence of canthaxanthin, 4-hydroxy-echinenone, 3-hydroxy-canthaxanthin and astaxanthin was confirmed in the carapaces of crab. In the internal organs, β-carotene, echinenone, isocryptoxanthin and astaxanthin were found. The following metabolic path-way from β-carotene to astaxanthin was proposed. β-carotene ?? isocryptoxanthin ?? echinenone ?? 4-hydroxy-echinenone ?? canthaxanthin ?? 3-hydroxy-canthaxanthin ?? astaxanthin