Bioaccessibility and content of Se in fish and shellfish widely consumed in Mediterranean countries: influence of proteins, fat and heavy metals.

Twenty samples of fish and seafood products were selected for determination of total and bioaccessible Se (i.e. soluble and dialyzable). The Se contents ranged between 0.638-0.052 µg/g. The samples of fatty fish such as mackerel and tuna showed higher contents than the species of lean fish, and mainly the fresh water fish, such as salmon, trout and panga showed the lowest contents. The fraction of soluble Se ranged between 43-84% while that the fraction of dialyzable Se did not exceed 14%. No statistically significant correlation was observed between protein content and total and bioaccessible Se content. In contrast, a negative interaction was observed between bioaccessible Se and fat content, and between bioaccessible Se and presence of heavy metals like Cd.