Abstract

The evaluation of the antioxidant activity of ten aqueous and methanol extracts of the red seaweeds, Pterosiphonia complanata, Boergeseniella thuyoides, Sphaerococcus coronopifolius, Asparagopsis armata, Halopitys incurvus, Hypnea musciformis, Gelidium spinulosum, Plocamium cartilagineum, Gelidium pulchellum and Ceramium rubrum was realized through three different tests. Using the DPPH (2,2-diphényl-1-picrylhydrazyl)  test, four methanol extracts allowed the transformation of DPPH radical in reduced form with an EC₅₀ between 96 and 862 µg.mL^-1. With respect to the β-carotene test, 7 methanol extracts showed activity against peroxide radicals with an EC₅₀ between 9 and 176 µg.mL^{-1. In the deoxyribose test, the inhibition percentage of hydroxyl radicals varies between 25 and 68% for five aqueous extracts; the most important being the extract of A. armata.}

Key words: Red algae, antioxidant activity, DPPH, Deoxyribose, β-carotene–linoleic acid system.