Season affects three insufficiently studied seaweed species (Bifurcaria bifurcata, Codium sp., Ericaria selaginoides): bioactivity alterations

Abstract

The biological activity and nutraceutical potential of two brown seaweed species (Bifurcaria bifurcata, Ericaria selaginoides) and one green seaweed (Codium sp.) were evaluated taking seasonal effects into account. The phenolic content of B. bifurcata was higher than those of the other two species regardless of season, 10.13–11.01 mg Gallic Acid Equivalent (GAE) g–1 dw seaweed. The ethanol extracts of B. bifurcata were more antioxidant as measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) technique than the equivalent extracts from E. selaginoides, 0.428–0.442 mg Ascorbic Acid Equivalent (AA Eq) g dw seaweed–1 vs 0.338–0.361 mg AA Eq g dw seaweed–1. Regarding Ferric Ion Reducing Antioxidant Power (FRAP), the highest activity was measured in Codium sp. extracts and no difference was detected between B. bifurcata and E. selaginoides. The 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) results differed from the FRAP values in that the ethanol extracts from Codium sp. were less antioxidant as measured by ABTS than those of the other two species. Summer E. selaginoides extracts were more antioxidant. The most anti-inflammatory extract was obtained from E. selaginoides harvested in Summer, exhibiting 94.2 ± 4.0% inhibition of cyclooxygenase-2 (COX-2). The extracts from Codium sp. had the lowest activity, 13.6–15.5%. For both B. bifurcata and E. selaginoides, Summer extracts were more anti-inflammatory than Winter extracts.