ena-STUDY-CIIMAR - Interdisciplinary Centre of Marine and Environmental Research-05-07-2020-22:31:37:495-1128
Deep sea microbial community: potential to remediate petroleum hydrocarbons
The present work aims to contribute for the study of deep sea microbial resources and for their exploitation for the development of biotechnological tools that can be used for bioremediation of petroleum hydrocarbon polluted environments.Deep sea sediment samples (~1000 m depth) were collected from four sample sites in North Atlantic Ocean. Autochthonous seafloor microbial assemblages were initially described by next-generation sequencing of the V4–V5 hypervariable region of the 16S ribosomal RNA (rDNA) gene.Then, the remediation potential of microorganisms previously isolated from the sentiment sampled and enriched in petroleum for 15 days was tested.A total of 26 isolates recovered from the enrichment process were identified. Among them, 8 strains from the first location (L1) were then assembled, and their degradation potential was tested in bioremediation experiments. The abundance of hydrocarbon degrading bacteria (HD), in the beginning and the end of the experiment, was estimated based on most probable number method (MPN). Prior to bioremediation experiments, petroleum and acetate enrichments were performed, with the assembled microbial consortia, in Bushnell-Haas medium (supplemented with 2% of NaCl) for 4 days. Then, in a microcosm experiment, 4 different treatments were tested: natural attenuation (N), biostimulation (BS), bioaugmentation with petroleum enrichment (BAp) and bioaugmentation with acetate enrichement (BAa) for 15 days.  Additionally, the microbial composition of cultures from the treatments BAp and BAa were analysed. At end of the experiment, 14 morphological different isolates were recovered from the two treatments, including most of those that were initially used to establish the microbial consortium. Furthermore, total petroleum hydrocarbons (TPHs) were determined by Fourier transform infrared spectroscopy analysis (FTIR) showing rates of crude oil degradation between 18% and 30%. Despite these degradation rates being relatively low, when compared with other studies, this is one of the first studies to describe the use of deep-sea microorganism for bioremediation experiments.
The present work aims to contribute for the study of deep sea microbial resources and for their exploitation for the development of biotechnological tools that can be used for bioremediation of petroleum hydrocarbon polluted environments.Deep sea sediment samples (~1000 m depth) were collected from four sample sites in North Atlantic Ocean. Autochthonous seafloor microbial assemblages were initially described by next-generation sequencing of the V4–V5 hypervariable region of the 16S ribosomal RNA (rDNA) gene.Then, the remediation potential of microorganisms previously isolated from the sentiment sampled and enriched in petroleum for 15 days was tested.A total of 26 isolates recovered from the enrichment process were identified. Among them, 8 strains from the first location (L1) were then assembled, and their degradation potential was tested in bioremediation experiments. The abundance of hydrocarbon degrading bacteria (HD), in the beginning and the end of the experiment, was estimated based on most probable number method (MPN). Prior to bioremediation experiments, petroleum and acetate enrichments were performed, with the assembled microbial consortia, in Bushnell-Haas medium (supplemented with 2% of NaCl) for 4 days. Then, in a microcosm experiment, 4 different treatments were tested: natural attenuation (N), biostimulation (BS), bioaugmentation with petroleum enrichment (BAp) and bioaugmentation with acetate enrichement (BAa) for 15 days.  Additionally, the microbial composition of cultures from the treatments BAp and BAa were analysed. At end of the experiment, 14 morphological different isolates were recovered from the two treatments, including most of those that were initially used to establish the microbial consortium. Furthermore, total petroleum hydrocarbons (TPHs) were determined by Fourier transform infrared spectroscopy analysis (FTIR) showing rates of crude oil degradation between 18% and 30%. Despite these degradation rates being relatively low, when compared with other studies, this is one of the first studies to describe the use of deep-sea microorganism for bioremediation experiments.