A new insight into the influence of habitat on the biochemical properties of three commercial sea cucumber species

This work makes a comparative evaluation of the biochemical profile of three sea commercial cucumber species (Holothuria mammata, H. polii and H. tubulosa) caught from different locations of the Mediterranean Sea (SE Spain). All species had high levels of moisture (from 73.6% in H. mammata to 81.2% in H. tubulosa), crude ash (from 9.61% in H. mammata to 14.7% in H. tubulosa) and protein (3.01% in H. tubulosa to 11.1% in H. mammata). They also had a low fat content, from 0.21% in H. tubulosa to 0.55% in H. mammata. Holothuria polii had intermediate values between the other two species, for all considered variables. All species had adequate protein/lipid ratios (H. mammata, 20:1; H. polii, 23:1; H. tubulosa, 14:1) and low lipid levels, enriched in omega-3 polyunsaturated fatty acids, especially arachidonic acid. The fatty acid profile suggests that H. polii is feeding on sediments more influenced by terrestrial inputs than the remaining species. Holothuria mammata and H. tubulosa are feeding on marine food sources mainly, but also with some terrestrial influence. The most abundant amino acids detected were alanine, arginine, glutamic acid, and glycine. All species had similar contents of essential amino acids (EAA) and ratios of EAA/non-essential amino acids. Holothuria tubulosa had a high content of toxic metals including Cr, Pb and Ni. This work highlights differences in compositional characteristics between different species of the same genus (Holothuria) from different locations.