Inhibition of fish oil oxidation and the radical scavenging activity of New Zealand seaweed extracts

Abstract

► Extracts form four algae ( Ecklonia radiata , Macrocystis pyrifera , Champia sp. and Porphyra sp.) were assessed for anti oxidative capacity. ► Brown algae lipid-soluble seaweed extracts generally displayed greater antioxidative capacity than red algae species. ► E. radiata is the most likely antioxidant for use as an oil systems as it perform better than commercially BHT. ► Potential use of seaweed extracts as an antioxidant in marine oils has been demonstrated. This study describes the potential use of New Zealand seaweed extracts as antioxidants in fish oils. The extracts from two brown seaweeds ( Ecklonia radiata , Macrocystis pyrifera ) and two red species ( Champia sp. and Porphyra sp.), were added to hoki ( Macruronus novaezelandiae ) oil and assessed by production of oxidation products in an elevated temperature (60 °C) storage trial. Antioxidant assays ORAC and DPPH were conducted to elucidate the radical scavenging activity of the seaweed extracts. The results showed that all the lipid-soluble seaweed extracts had some antioxidative capacity, with brown algae generally outperforming red algae species. Extracts from E. radiata performed best with significantly lower primary, secondary and total oxidation products, and higher DPPH radical scavenging ability than the commercial antioxidant, BHT. This study demonstrated the potential of brown algae seaweed extracts, in particular E. radiata , for use as antioxidants in fish oil products.