Recovery of mangrove sediment contaminated with fuel oil by endogenous microbial consortium

This work aimed to select a microbial consortium enriched with isolated microorganisms of mangrove sediment as to its capacity to recover sediment contaminated by lubricating oil. The promising microorganisms were selected using the colorimetric dichlorophenol indophenol technique (DCPIP) using lubricating oil as the carbon source, to evaluate the emulsifying and enzymatic activity of the microorganisms. The antagonism test was also used for further evaluation of the consortia. The fractional factorial experimental design methodology (2n) was used to establish the process conditions for the subsequent accomplishment of the degradation kinetics of the lubricating oil by the selected microorganisms and consortium. Eight bacteria and three fungi were evaluated, of which five were selected with a 36 h turn of the DCPIP indicator. Eleven microorganisms produce emulsifying substances and five produce enzymes. The results showed that the best consortium was B5F2F4, with a degradation rate of 95% of the phenol at 70 rpm in 250 μL of the oil. The kinetics of oil degradation showed a phenol degradation rate of 65% after 24 days of treatment. The microorganisms are suitable for the degradation of phenol, the main constituent of the oil, and can be used as a recovery model for environments contaminated with hydrocarbons.