Antioxidant activity and related chemical composition of extracts from Brazilian beach-cast marine algae: opportunities of turning a waste into a resource

Beach-cast marine algae are a potential biomass for several biofunctional products and occur in large volumes in some coastal regions due to natural current processes or drifting algae like pelagic Sargassum. Antioxidant activity and chemical composition of methanolic and aqueous extracts from fifteen beach-cast marine algae from the Brazilian Coast were evaluated. In general, the highest antioxidant activities were found in extracts from brown macroalgae followed by the extracts of red algae, and the lowest activities were detected in the green beach-cast algae. The concentrations of phenolic compounds and carbohydrates exhibited a positive correlation with the antioxidant activities of the tested extracts. To the best of our knowledge, this is one of the few worldwide studies concerning beach-cast seaweeds and antioxidant activity and related antioxidant metabolites. This study suggests that these algae are potential sources for obtaining extracts with antioxidant properties, rich in phenolic compounds and sulfated carbohydrates. Beach-cast macroalgae are unused biomass and the beneficial utilization of this biomass for prospection of natural products and functional foods is suggested.

Automated summary

The study evaluated the antioxidant activity and chemical composition of methanolic and aqueous extracts from fifteen beach-cast marine algae from the Brazilian Coast. It found that brown macroalgae exhibited the highest antioxidant activities, followed by red algae, while green beach-cast algae had the lowest activities. The concentrations of phenolic compounds and carbohydrates showed a positive correlation with the antioxidant activities of the tested extracts.