Secondary metabolites and pigments in the tissues and diet of the sea cucumber, Holothuria atra from the Great Barrier Reef

Three specimens of Holothuria atra were collected from Palfry Island in the Lizard Island group in December 1995, a week before mass spawning occurred. The sea cucumbers were kept alive in an aerated tank with running seawater, which contained sand, coral rubble and sediment from their natural habitat. After 14 days, the sea cucumbers were frozen and then the ovaries, epidermal tissues, viscera and gut content were removed. Additional sediment from the natural habitat was also collected.Tissue samples, gut contents and sediment were then processed to extract, separate and identify the metabolites and pigments present. This research was undertaken to determine the identity and concentration of metabolites and pigments occurring in the dorsal skin, gut contents, viscera and mature eggs of Holothuria atra and in the sediments of its natural habitat. The distribution of these metabolites and pigments within each tissue type, the gut contents and the sediment may give some insight into the origin and roles of these compounds.