Biorefinery as a tool to obtain multiple seaweed extracts for cosmetic applications

Abstract

Seaweeds have been identified as a valuable source of natural ingredients and their use in cosmetics is being studied increasingly. This work sought to understand the possible uses of three species of brown algae present along the Portuguese coast: Bifurcaria bifurcata, Saccorhiza polyschides and Fucus spiralis. Considering the idea of more sustainable use of resources, two extracts (water (W) and ethanol (E)) and two fractions (polysaccharides (P) and residues (R)) were obtained employing a biorefinery process. The extracts and fractions were evaluated in terms of antioxidant capacity (ABTS•+, DPPH•, •NO, O2•− and FRAP assays), anti-hyperpigmentation capacity (tyrosinase inhibition), and evaluated in terms of biocompounds (phenolic compounds and pigment content). The biochemical analysis revealed that F. spiralis contain more lipids and carbohydrates than the other species, while S. polyschides has more proteins and ashes. Fucus spiralis showed the most promising results, regarding the antioxidant assays, tyrosinase inhibition, highest phenolic compound concentration, total chlorophylls and total carotenoids. In a biorefinery concept, F. spiralis from the autumn season would be the most promising candidate as all extracts and fractions have potential commercial value. Bifurcaria bifurcata also has its merits in antioxidant activities and the content of phenolic compounds.