Overproduction of Antioxidants by some Algae under certain Ecological Stresses

In order to explore natural antioxidants and replace harmful synthetic ones, twenty four microalgal species belonging to Cyanophyta and Chlorophyta were screened for the highest levels of antioxidants and their activities. The results showed that the antiInvestigations of the growth, biomass yield and antioxidants under different stress conditions (pH, heavy metals and salinity) of Spirulina platensis and Chlorella ellipsoidea were performed. The maximum production of antioxidants was achieved at 2.5ppm F