In our previous study it was demonstrated that the
active principal antimicrobial compound extracted from
the cyanobacterium Nostoc muscorum was a phenolic
compound (El-Sheekh et al., 2006). The present work is
an attempt to demonstrate the antibacterial and antifungal
activity of Anabaena wisconsinense and Oscillatoria
curviceps. These species were isolated from Abbassa fish
farm in Egypt and are the dominant species in the farm.
The extracts from these algae were also used in vivo
to protect the fish from pathogenic bacterial and fungal
infections.