Metabolomics of diesel oil contaminated soil after bioremediation

Abstract

The diesel oil is the main fuel in the Brazilian energy matrix, being the most commercialized petroleum derivative in Brazil. This fuel is a complex mix of hydrocarbons and due to its recalcitrance and frequent spill accidents, it is worldwide recognized as a threat to aquatic and terrestrial ecosystems. Several techniques are available for the remediation of hydrocarbon-contaminated sites. However, bioremediation is considered a promising alternative since it is more sustainable, efficient, and cost-effective when compared to other remediation technologies. Our research group has been studying different treatments, aiming at achieving the best result of diesel oil degradation in contaminated soils. The results obtained up to now highlighted the efficiency of the consortium A (composed of two fungi from marine origin) in degrading diesel oil from contaminated soils, and in helping in the understanding of the interaction between the microbial consortium and the soil microbial community, in favor of diesel oil degradation. Due to the immense microbial diversity and the biotic and abiotic processes that regulate microbial activities in the soil, microbial responses during the biodegradation of hydrocarbons are still obscure for this environment. In this way, for metaproteomic analysis, we consolidated a partnership with the renowned researcher in the area, Prof. Mario Sergio Palma (UNESP/Rio Claro), an expert in mass spectrometry that has been working with metaproteomics and structural dynamic studies of proteins and peptides. Although metagenomic and metaproteomic studies provide important information within biological systems, complete understanding will only be gained by engaging the metabolome approach. Metabolites are biomolecules that depend on the environmental context, reflecting on chemical changes from the interaction between the metabolism products of organisms and environmental attributes. Therefore, this study aims to combine data from metagenomics (genes), metaproteomics (proteins) and metabolomics (metabolites) to improve knowledge about global metabolism during the diesel bioremediation process and its transformation pathways, in order to understand more fully the mitigation of this environmental pollutant.