Chemical Composition and Nutritional Value of Different Seaweeds from the West Algerian Coast

Abstract

Analysis of proximate composition, lipid fraction (fatty acids and lipid classes), macroelements, and trace elements was carried out on brown (Cystoseira stricta; Cystoseira compressa), red (Corallina elongata), and green (Enteromorpha compressa; Ulva lactuca) seaweeds collected from the west Algerian coast to assess their nutritional value. Protein, lipid, carbohydrate, and ash content (g kg−1 dry alga) was in the ranges 58.5–141.4, 6.4–27.1, 134.0–461.1, and 246.1–764.2, respectively. The lowest caloric value was obtained for C. elongata (827.6 kcal kg−1 dry alga); the remaining values being in the range 2,106–2,479 kcal kg−1 dry alga. C. elongata and C. stricta provided the highest polyunsaturated fatty acid content, while a valuable n-6/n-3 ratio of between 0.95 and 4.20 was obtained for all species. α-Tocopherol was present in all seaweeds; the highest level was obtained in U. lactuca. Macroelements K and Na were predominant in C. compressa and C. stricta; while Mg and Ca were most abundant in E. compressa and C. elongata, respectively. In all cases, a healthy Na/K value < 0.7 was observed, and a profitable ion quotient ratio was observed in all cases, except for C. elongata. Estimated daily intake of most minerals from the algae studied is lower than the corresponding recommended daily intake.