Radical-scavenging activity of Aegean Sea marine algae

In the present work, thirteen algae from the Aegean Sea were examined for radical-scavenging activity (RSA) using the DPPH and chemiluminescence (CL) tests. Extracts of the brown alga Taonia atomaria exhibited the best RSA in comparison to the extracts of the other investigated species and approached the activity of powerful antioxidant standards. Column chromatography separation of T. atomaria extract, followed by preparative HPLC, resulted in the isolation of six metabolites, which were identified by spectral analyses (1H NMR, 13C NMR and MS). The isolated metabolites taondiol, isoepitaondiol, stypodiol, stypoldione, sargaquinone and sargaol were found to possess marked RSA.