Hydrocarbon-Degrading Microbial Consortia for Oil Drilling Waste Treatments in Arid Environments

Bioremediation is a promising environmental friendly strategy for the treatment of oil drilling waste, which is particularly challenging in arid areas concerned by high petroleum production activities. Microbial consortia adapted to such environmental conditions are required for the implementation of bioaugmentation treatments. Here four metal(loid)s-resistant hydrocarbon-degrading microbial consortia growing at 40 °C were obtained from oil drilling waste maintained in different phyto-management conditions. The microbial consortia exhibited different microbial compositions with the capacity to degrade 15 to 35% of total petroleum hydrocarbon in 15 days. The hydrocarbon degradation resulted in different hydrocarbon fraction profiles underpinned by the presence of 14 specific OTUs revealed by linear discriminant analysis effect size (LEfSe). Each consortium was characterized by the presence of genera groups, defined according to their correlation with the hydrocarbon fractions, explaining their different degradation capacity and the resulting hydrocarbon fraction profiles. Thus, these consortia can be used in combination or successively to implement bioremediation strategies for the treatment of multi-contaminated oil drilling waste in arid environments.