First determination of photosynthetic pigments in surface sediments from the continental shelf and slope of the northwestern Gulf of Mexico

ABSTRACT Marine pigments are more commonly used in food, pharmaceuticals, aquaculture and cosmetics industries. Marine pigments have a significant economic importance, constituting a multimillion-dollar industry that is still growing. Considering this, we decided to conduct a descriptive study of the photosynthetic pigments in surface sediments from the continental shelf and slope of 14 sites located in the northwestern Gulf of Mexico, obtained during October-November 2012. These pigments were analyzed using high-performance liquid chromatography. At least one pigment was detected in 10 of the samples examined, and a total of six pigments were identified, including three photosynthetic pigments and three chlorophyll-a degradation products: pheophorbide-a, pyrophaeophytin-a and phaeophytin-a. The pigments with the highest concentration were β-carotene and pheophorbide-a. Significant pigment concentrations were observed in inshore areas exposed to the influence of river discharge (Bravo and Soto La Marina) and Laguna Madre. The pigment composition and concentration were influenced by depth, temperature, salinity, and nickel concentration. Finally, a correlation between Ni, an indirect hydrocarbon contaminant marker, and pigment concentrations was observed. A deeper understanding of marine pigments certainly will fuel advances in biotechnology and bioengineering. We find it crucial to recognize the interactions between marine pigments and other ecosystem components. Despite pigment diversity, exploration in this field is still in its first stages, with many marine compounds awaiting further exploration.