EFFECT OF BIOFILM FORMATION BY PSEUDOMONAS 8909N ON THE BIOAVAILABILITY OF SOLID NAPHTHALENE

The effect of biofilm formation by Pseudomonas 8909N (DSM no. 11634) o n the dissolution and biodegradation rates of solid naphthalene was qu antified. Biofilms were cultivated on solid naphthalene as a model pol ycyclic aromatic hydrocarbon in continuous cultures. After different p eriods of incubation, the dissolution rate of naphthalene was determin ed by batch dissolution tests with active or inactivated biofilms and without biofilms. Results show that the naphthalene dissolution rate t o the bulk liquid phase was reduced by over 90% after 7 days of biofil m formation. The degradation of naphthalene in the biofilm proved to b e insignificant compared to the decrease in the bulk liquid conversion of naphthalene, and the overall biodegradation rate of the solid naph thalene decreased.