Electrochemistry-guided isolation of antioxidant metabolites from Sargassum elegans

► Use of cyclic and square-wave voltammetry in the isolation of antioxidants. ► Guided by oxidation potential and area under anodic peak. ► Isolation of antioxidant metabolites from Sargassum elegans. ► Main antioxidant compounds were fucoxanthin and sargaquinoic acid derivatives.