Screening of Microalgae for Antioxidant Activities, Carotenoids and Phenolic Contents

Ten different microalgal species were screened for their antioxidant activity using 2,2' diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, both total phenolic and carotenoid contents were determined. The ethanolic extract of Oscillatoria sp. showed the highest antioxidant activity (69.1 %), while the green Chlorella sp. showed higher phenolic content (39.1 mg GAE g(-1) dry wt.) and Scenedesmus obliquus recorded higher carotenoid content (3.73 mg L-1), than cyanobacterial species Microalgal biomass plays a great role as a potential source of natural antioxidants, not only due to the carotenoids but also the phenolic compounds.