Crude sulfated polysaccharides extracted from marine cyanobacterium Oscillatoria simplicissima with evaluation antioxidant and cytotoxic activities

Background and Objectives: Microalgae have been widely used as a novel source of bioactive substances. These substanc- es exhibit various biological actions including, antioxidant and antitumor effects material. The present work is carried out to evaluate potential applications of cyanobacterium Oscillatoria simplicissima containing mainly polysaccharides. Materials and Methods: Crude polysaccharides from marine cyanobacteria Oscillatoria simplicissima and Oscillatoria acutissima were extracted and characterized according to their chemical content and cytotoxic activities. The isolated poly- saccharides characterized by the Fourier transmittance infrared spectrum (FT-IR). Results: These polysaccharides constituted 34.68 mg/g of sugar, 0.011 mg/g of protein, and 28.92 mg/g of sulfate contents. The antioxidant property of the methanol extracts of these green microalgae was evaluated by measuring the free radical scavenging activity by the DPPH assay method. The algal extracts were then evaluated for their suppressive effect on tumor cell growth (A-549, MDA-MB-231, PC-3, HT-29, HepG2, and HeLa) by using the SRB assay. At a concentration of 10 mg/ mL, Oscillatoria simplicissima exhibits an antioxidant activity of 45.97%. The cytotoxic activity revealed that Oscillatoria simplicissima polysaccharide shows potent cytotoxic activity against lung cancer (A-549) cell line 49.465 μg/mL. Conclusion: Microalgal polysaccharides have great therapeutically potential in drug development used as antitumor and antioxidant agents in near future.