Abstract

As the world population increases, the need for energy resources increases and for decades, petroleum has sustained this demand. Oil spill during petroleum extraction and processing has a negative impact on the environment. Methods that can decrease the impact of xenobiotic compounds on the environment have been developed. Among many bioremediation methods described, microbial remediation is of great importance. Our previous work demonstrated that Organic Waste Composting Unit (OWCU) located at the São Paulo Zoo Foundation (FPZSP) had a great diversity of microorganism. In the present work, we viewed this environment searching for xenobiotic degrading microorganisms by sampling the composting at various stages of the process with the aim of isolating the bacteria that would break down n-hexadecane, a model compound for hydrocarbon degradation. Two bacterial collections were assembled and tested in a 96-well plate model using n-hexadecane as a sole carbon source. Among the 418 isolates screened, eight were selected based on their ability to assimilate n-hexadecane. Molecular identification revealed their genus and species which are associated with xenobiotic degradation activities in different microbial consortia. However, these microorganisms have not being isolated from the same transforming process. Future studies with these isolates may shed light on the bacteria hydrocarbon degradation mechanism.

Key words: Composting, crude oil degrading microorganism, bioremediation, n-hexadecane degrading bacteria.