Characterization of hydrocarbon degrading bacteria at EPEA Station (38º 28’ S – 57º 41’ O) Atlantic coast

Abstract

Hydrocarbon degrading bacteria (HDB) were monitored since 2006 to 2018 at the Permanent Environmental Studies Station (EPEA), in order to analyze its abundance and the potentiality to metabolize these pollutants. The presence of HDB was detected with counts values ranging between 103 and 105 UFC ml-1. A slight increase was observed over time, which could be linked to changes in marine temperature reported within the last years. Thirty-six HDB were tested for growth on various hydrocarbons and some of them showed a broad biodegradation profile. Moreover, from phenanthrene (Phe) enrichment cultures, five strains were phylogenetically identified as Halomonas sp. E1, E2 and E3; Rhodococcus sp. E4 and Pseudomonas sp. E5. Complete Phe degradation was demonstrated for E4 and E5 strains, while E1, E2, E3 and E4 strains displayed surfactant production. This study contributed with the first knowledge about the intrinsic HC biodegradation potential by bacterial communities at EPEA. Some of the strains exhibited physiological properties that might have ecological significance on environmental alterations as the presence of pollutants. Particularly, Rhodococcus sp. E4 could be an alternative for microbial selection in the degradation of PAHs. Further studies are needed to evaluate the impact of the climate change on microbial-mediated detoxification processes.