SMALL-MOLECULE ANTIOXIDANTS IN MARINE ORGANISMS - ANTIOXIDANT ACTIVITY OF MYCOSPORINE-GLYCINE

The antioxidant activities of aqueous extracts of tissues from four di fferent marine species containing mycosporine-like amino acids were ex amined by their peroxyl radical-trapping abilities using the phosphati dylcholine peroxidation inhibition assay, The coral trout (Plectropomu s leopardus) lens extract had low oxidation inhibition activity; Porph yra tenera and Lissoclinum patella extracts had moderately strong inhi bition activities while the aqueous extract of Palythoa tuberculosa sh owed the greatest oxidation inhibition activity of the extracts tested ; the last two extracts contained mycosporine-glycine. In these sample extracts, mycosporine-glycine was reactive to peroxyl radicals wherea s the iminomycosporine-like amino acids, shinorine, porphyra-334, paly thine, asterina-330 and palythinol, were oxidatively robust. Purified mycosporine-glycine inhibited peroxyl radical-initiated autoxidation o f phosphaditylcholine in a concentration-dependent manner. These resul ts suggest that mycosporine-glycine may function as a biological antio xidant in marine organisms.