Fatty acid profile of Cystoseira C. Agardh (Phaeophyceae, Fucales) species from the Tunisian coast: Taxonomic and nutritional assessments

A screening of the total lipids and fatty acids (FAs) of 11 brown algae species of the genus Cystoseira (Phaeophyceae, Fucales) from the Tunisian coast is presented and discussed. Cystoseira species showed low total lipid content, ranging from 19.8 to 68.2 mg.g(-1) dry weight. Fourteen major FAs were detected in the lipid extract of Cystoseira. The FA profile of lipid extracts was characterized by high amounts of saturated FAs (SFAs) ranging from 40.51% to 57.91% of total FAs, with predominance of the lipid fraction of palmitic acid (>30% of total FAs). The arachidonic acid (C20:4n-6) levels were found to be significantly high, ranging from 8% to 16% of total FAs. Multivariate analyses of FA composition showed low geographic differentiation, providing further evidence of intraspecific diversity. Cystoseira crinita, Cystoseira schiffneri, Cystoseira amentacea var. stricta, and Cystoseira sedoides stood out for their low polyunsaturated fatty acid (PUFA)/SFA ratios, low n-6/n-3 PUFA ratios, high unsaturation, and low atherogenicity and thrombogenicity indices, suggesting high nutritional value.