Maya Crude-Oil Degradation by a Bacillus licheniformis Consortium Isolated from a Mexican Thermal Source Using a Bubble Column Bioreactor

Abstract

Thermophile microorganisms play an important role in hydrocarbon degradation due to being adapted to extreme conditions of temperature, and different species are capable of resisting thermophile conditions. In this study, we evaluated the oil-degrading capacity of seven thermophilic bacterial strains. Maya crude oil, a type of Mexican heavy oil, was selected as carbon source, and residual hydrocarbon concentration (TRH) was used as indicator of microbial degradation crude oil. Only four strains presented could degrade hydrocarbons, and these strains were molecularly identified using 16s region amplification and showed homology with Bacillus licheniformis. Using a bubble column reactor, the identified strains were evaluated (together in a consortium) for hydrocarbon degradation at 45, 50 and 55 °C. Concentration of TRH was decreased to 77.70, 58.19 and 51.90 % at 50, 45 and 55 °C, respectively. The consortium showed substantial potential for degrading Maya crude oil at 50 °C.