Program

The cyanobacterium Microcystis aeruginosa can potentially proliferate in a wide range of freshwater bionetworks and create extensive secondary metabolites which are harmful to human and animal health. It is essential to eliminate them from the ecosystem with convenient method. The conventional coagulation and sand filtration can eliminate particulate cyanobacterial cells but it takes more time. In the present study, we examined the growth inhibition effect of green synthesized copper oxide nanoparticles and magnetic nanoparticles against M. aeruginosa. The green synthesized copper oxide nanoparticles exhibit at the inhibition efficiency of 89.7 %.  Furthermore, we analyzed the mechanism behind the cytotoxicity of M. aeruginosa induced by copper oxide nanoparticles through evaluating membrane integrity, reactive oxygen species (ROS), and mitochondrial membrane potential (Δψm) level. The results expose that there is a loss in membrane integrity with ROS formation that leads to alteration in the Δψm, which ends up with severe mitochondrial injury in copper oxide nanoparticles treated cells. The magnetic nanoparticles exhibit at the lower amount and less time enough to remove the cyanobacteria cells. Results show that only small additions (1 mg) of magnetic nanoparticles were found high removal efficiency (~ 93%) with a residual. After magnetic treatment the previously greenish colour water turned to crystal clear, especially when high particle concentration was used, indicating effective removal of microalgae. Hence, green way synthesized copper oxide and engineered nanoparticles may be a useful selective biological agent for the control of M. aeruginosa.

Key words:  Harmful algae, Microcystis aeruginosa and nanoparticles.