Isolation and Characterization of Oil-Degrading Bacteria from Bilge Water

Twenty-one oil-degrading bacteria were isolated from bilge water. Based on a high growth rate on crude oil and on hydrocarbon degradation ability, 7 strains were selected (from 21 isolated) for further studies. 16S rRNA gene sequencing showed that isolated strains were affiliated to Bacillus, Pseudomonas and Halomonas genera; in particular, isolate BW-B12 (Bacillus sp., 99%), BW-C12 (Halomonas boliviensis, 99%) and BW-E12 (Halomonas boliviensis, 98%) were the best crude-oil degraders; after 10 days of cultivation in ONR 7a mineral medium supplemented with crude oil as single carbon source BW-B12, BW-C12 and BW-E12 showed a degradation rate of 80, 60 and 59%, respectively. The strains showed…