Potencial para produção de biossurfactantes em bactérias isoladas de macrófita aquática na Amazônia

Abstract

In the process of petroleum hydrocarbon biodegradation is a direct relationship between the degradation of these compounds and the production of biosurfactants. These molecules have attracted much commercial interest because its lower cost and higher efficiency than synthetic surfactants. This study verified the potential for the production of biosurfactants by evaluating emulsification activity in bacterial strains isolated in selective medium from the Amazon macrophyte Eichornnia crassipes and selected those with the greatest potential. Growth of strains was evaluated in mineral medium with hydrocarbon mixture and mineral medium with crude oil. The index of toxicity was evaluated in extracts of media with hydrocarbon mixture of five linhagenss that showed better growth. In the middle with crude oil there was better bacterial growth, highlighting the strain Stenotrophomonas sp. which reached about 13,4x106 CFUs / mL. The bacterial growth in the media used indicated the degradation of petroleum hydrocarbons, considering that these were the only carbon source. The strains that showed best results were Stenotrophomonas sp., Klebsiella sp., Enterobacter sp., Methylobacterium radiotolerans and Acinetobacter baumannii. They stood out in the production of biosurfactants the Stenotrophomonas sp strains and Methylobacterium radiotolerans, with better results in the middle with oil. The indices of toxicity showed better results in extracts of bacterial growth compared to the extracts controls. Thus, it is considered that the studied strains have significant potential as biosurfactants producing deserves additional studies to prove this production. Keywords: Bacteria; macrophyte, biosurfactants bioremediation, Amazon.