Efficient and eco-friendly mixed bacterial consortium for petroleum wastewater treatment: Effect of the bio-augmentation and biosurfactant addition on hydrocarbon biodegradation

Abstract

In the present investigation, we aimed to study biological petroleum wastewater treatment. A bioprocess based on the use of a mixed bacterial consortium along with the addition of Biosurfactant (BioS) and bioaugmentation with BioS producing strains were evaluated. The consortium was the combination of two bacterial strains with the capacity to metabolize hydrocarbons, Baci and B201. Two other strains BH1 and BSS2 selected for their ability to degrade hydrocarbons as well as to produce BioS were also exploited. The effect of ex-situ and in-situ produced BioS on hydrocarbon biodegradation were compared. Obtained results demonstrated a moderate capacity to remove crude oil from contaminated water of about 47% for the consortium. The best improvement of hydrocarbon biodegradation of about 84% was obtained when adding BH1 derived BioS solely. However, ex-situ produced BioS exhibited better results. Regarding the wastewater characteristics, we note a decrease of the COD/BOD5 Ratio to reach 2.64. Thus, the wastewater became easily biodegradable. The described bioprocess is of great interest for the bioremediation of petroleum effluents. BioS addition as well as bioaugmentation enhanced crude oil removal.

Graphical abstract

Keywords:

• Biodegradation
• petroleum effluent
• bioprocess
• bacterial consortium
• biosurfactant

Acknowledgements

This work has been supported by grants from the Tunisian Ministry of Higher Education, Scientific Research and Technology. It is a part of a research project on BioS production, characterization and application.

Authors’ contributions

All authors directly participated in the planning, execution, or analysis of this study. All authors read and approved the final manuscript. The first Author Doctor Ameni Ktata realized and wrote the paper. The second author Doctor Inès Mnif designed the experimental part of the present work and participates in the redaction and interpretation of the results. The third and fourth Authors Doctor Sameh Ben Mabrouk and Doctor Ons Mrabet contributed in the realization of the work. The fifth author Doctor Aida Karray contributed in the design and redaction of the work. The sixth author Professor Slim Cherif is the head of laboratory and the project working on BioS production and valorization.

Consent for publication

All authors read the final manuscript and approved its submission to Journal of Dispersion Science and Technology.

Data availability statements

The data sets supporting the conclusions of this article are included in the article.

Disclosure statement

The authors declare that they have no competing interests.

Novelty statement

The present work valorized a novel bacterial consortium for the efficient biodegradation of crude oil contaminated water. Accordingly, bio-augmentation with biosurfactant producing strain and biosurfactant addition increase the biodegradation potency.

Additional information

Funding

Funding for this research work was granted by the Ministry of Higher Education and Research of Tunisia.