LAUSR

BACKGROUD In recent years, research on the bioactive properties of macroalgae has increased, due to the great interest in exploring new products that can contribute to improve human health and well-being. In the present study, the antioxidant and antimicrobial potential of six different brown algae of the Fucales order were evaluated, namely Ericaria selaginoides, Ericaria amentacea, Gongolaria baccata, Gongolaria usneoides, Cystoseira compressa and Sargassum vulgare (collected along the Mediterranean and Atlantic coasts). The antioxidant capacity was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, the Oxygen Radical Absorbent Capacity (ORAC) and the Ferric reducing antioxidant power (FRAP) and were related to the total phenolic content (TPC). The antimicrobial activity was evaluated measuring the growth inhibition of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans. RESULTS The highest antioxidant capacity was obtained for Ericaria selaginoides revealing the highest capacity to scavenge DPPH radical (EC50  = 27.02 μg/mL), highest FRAP (1761.19 μM FeSO4 E/ g extract), high ORAC (138.92 μmol TE/g extract), alongside to its high TPC (121.5 GAE/ g extract). This species also reported the highest antimicrobial capacity against Staphylococcus aureus (IC50  = 268 μg/mL). CONCLUSIONS Among all studied seaweed, Ericaria selaginoides reveals the highest antioxidant and antimicrobial activities, and thus should be explored as a natural food additive and/or functional ingredient. This article is protected by copyright. All rights reserved.