Pigmentation and Spectral Absorbance Signatures in Deep-Water Corals from the Trondheimsfjord, Norway

Abstract

The pigmentation and corresponding <em>in vivo</em> and <em>in vitro</em> absorption characteristics in three different deep-water coral species: white and orange <em>Lophelia pertusa</em>, <em>Paragorgia arborea</em> and <em>Primnoa resedaeformis</em>, collected from the Trondheimsfjord are described. Pigments were isolated and characterized by High-Performance Liquid Chromatography (HPLC) analysis and High-Performance Liquid Chromatography Time-Of-Flight Mass Spectrometer (LC-TOF MS). The main carotenoids identified for all three coral species were astaxanthin and a canthaxanthin-like carotenoid. Soft tissue and skeleton of orange <em>L. pertusa</em> contained 2 times more astaxanthin g⁻¹ wet weight compared to white <em>L. pertusa</em>. White and orange <em>L. pertusa</em> were characterized with <em>in vivo</em> absorbance peaks at 409 and 473 nm, respectively. <em>In vivo</em> absorbance maxima for <em>P. arborea</em> and <em>P. resedaeformis</em> was typically at 475 nm. The shapes of the absorbance spectra (400–700 nm) were species-specific, indicated by <em>in vivo</em>, <em>in vitro </em>and the corresponding difference spectra. The results may provide important chemotaxonomic information for pigment when bonded to their proteins <em>in vivo</em>, bio-prospecting, and for <em>in situ</em> identification, mapping and monitoring of corals.

Keywords

• astaxanthin
• canthaxanthin
• optical characteristics
• &lt;em&gt;Lophelia pertusa&lt;/em&gt;
• &lt;em&gt;Paragorgia arborea&lt;/em&gt;
• &lt;em&gt;Primnoa resedaeformis&lt;/em&gt;