Comparative analysis of the nutritional profiles of five edible macroalgae as sustainable food sources

Seaweed aquaculture holds great promise as a solution to the global challenge of sustainable food production by providing alternative, resilient food sources. This study investigated the nutritional and biochemical profiles of five partially underutilized macroalgal species (Botryocladia pseudodichotoma, Caulerpa cylindracea, C. lentillifera, C. racemosa, and Codium taylorii) to assess their potential as sustainable and nutritious food sources. The proximate composition, including moisture, lipid, carbohydrate and protein content, as well as the fatty acid, pigment, and elemental compositions were analyzed along with antioxidant activity and total phenolic content. All species showed high levels of polyunsaturated fatty acids (PUFAs, 39.3–59.6% of total FAs), especially omega-3 FAs. The green algae exhibited strong antioxidant activities and high total phenolic contents with highest values in Caulerpa racemosa (277 mmol Trolox Equivalents (TE) 100 g− 1 dry weight (DW) and 157 mg Gallic Acid Equivalents (GAE) 100 g− 1 DW, respectively). The red alga Botryocladia pseudodichotoma displayed the comparatively highest lutein content (0.07 mg g− 1 DW), almost three times higher than in the green algae. Elemental analysis revealed a promising mineral profile of all species, with high levels of essential minerals such as calcium, magnesium, and potassium. The findings highlight the potential of these macroalgae as sustainable and nutritious dietary resources, capable of addressing health and environmental challenges. The study also emphasizes the importance of species diversification in aquaculture, as no single species provides all essential nutrients.