Résumé
Five freshwater algal species were isolated from Nile River and studied for their biological (cytotoxic and antiviral activity) in order to test their benefit in the Egyptian drinking water source. The algal species were isolated and identified as: Anabaena sphaerica, Chroococcus turgidus, Oscillatoria limnetica, and Spirulina platensis (blue – green algae, Cyanobacteria) and Cosmarium leave (green algae). They were cultivated using a Photobioreactor and purified using BG11 media. Twenty five grams of each of the five powdered algal species were extracted with MeOH till exhaustion to give five methanolic extracts for Anabaena sphaerica, Chroococcus turgidus, Oscillatoria limnetica, Spirulina platensis and Cosmarium leave respectively. The residues left were extracted with distilled H2O at 50oC to give five aqueous extracts respectively. The cytotoxicity of all the extracts was tested on Hep-2 cell line and their antiviral assays were tested on Adenovirus Type 40 as a preliminary testing. Nested PCR was carried out for confirmation of Adenovirus. Antialgal inhibitory effect on algal community was carried out. Results revealed that the non toxic concentrations for all the extracts were 2mg/ml and Spirulina platensis methanol and water extracts were active alga as antiviral (50% and 23.3% of reduction respectively).