Bioactive pigments from microalgae Phormidium autumnale

- The characterization of pigments of the microalgae Phormidium autumnale is reported.
- The peroxyl radical scavenging capacity of pigments extracts was assessed.
- Phormidium autumnale can be considered a potential source of bioactive pigments.

The profile of the three classes of pigments (carotenoids, chlorophylls and phycobiliproteins) and the peroxyl radical scavenger capacity of extracts from microalgae Phormidium autumnale were determined. Twenty-four carotenoids, three phycobiliproteins and two chlorophylls were identified. The major carotenoids of biomass were all-trans-β-carotene (225.44 μg·g− 1), all-trans-lutein (117.56 μg·g− 1) and all-trans-zeaxanthin (88.46 μg·g− 1). Furthermore, characteristic carotenoids in cyanobacteria such as echinenone (79.07 μg.g− 1), myxoxanthophyll (18.83 μg.g− 1) and canthaxanthin (1.89 μg·g− 1) were found. The chlorophyll a (2.700 μg·g− 1) and C-phycocyanin (2.05 × 105 μg·g− 1) were predominant pigments in the other fractions of color compounds from biomass. The carotenoid and chlorophyll extracts were shown to be potent scavengers of peroxyl radical, being almost 28 and 85 times more potent α-tocopherol respectively, and for phycobiliproteins, the antioxidant capacity was 274 μmol trolox·g− 1 (dry wt).