Identification of Culturable Bacteria from Biofilms Formed on Steel Panels Immersed in Two Different Marine Sites in Northern Coast of Tunisia

Biofouling, has considerable economic consequences. The present study describes identification of fouling bacteria obtained from two different geographic areas in northern coast of Tunisia. Isolated strains were also investigated for their enzyme producing capacity. Treated steel panels were immersed in shallow water for seven days. To specify microbial communities of culturable bacteria, microscopic approaches and 16S rDNA sequencing were used and bacterial species diversity was characterized. Phylogenetic analysis indicated that they belonged to Firmicutes, Proteobacteria, and Actinobacteria phyla. All of biofilm isolated bacteria produced amylase and 67% of tested strains produced cellulase. The highest levels of enzymatic activities found in the polluted area with strains isolated from La Goulette Harbor. Significant variations of enzymatic activities were detected in relation to different geographical regions. The present study gives information about marine bacteria from southern Mediterranean sea, at first stage forming biofilm. It highlights their extracellular enzymatic activity as potential source for biotechnologic uses.