Biotechnological potential of microorganisms from landfill leachate: isolation, antibiotic resistance and leachate discoloration

Disposal of municipal solid waste (MSW) can be considered a risk to human health representing a great environmental problem in several countries. MSW landfills are a significant source of toxic elements in the environment. Microorganisms able to thriving in leachate wastewater may exhibit metabolic machinery to synthesize a wide range of enzymes able to degrade and/or discolor toxic compounds from leachate. The use of non-pathogenic microbial cells for human health, recovered from leachate for biotechnological application, can be considered a promising approach in bioremediation processes of toxic compounds found in these environments. The present work aimed to the isolation, antibiotic resistance evaluation and leachate discoloration by microorganisms isolated from landfill leachate of Foz do Iguaçu. Forty bacteria and fifteen filamentous fungi were isolated. From these, six bacterial showed resistance at least one tested antibiotic, while six fungal isolates showed resistance to the antimycotic nystatin. CCMIBA_4L (unidentified bacteria) and Paecilomyces sp. CCMIBA_5N, were able to discolor 19.15% and 25.26% of the leachate, respectively. The results of the present work encourage future studies to characterize the enzymes involved in the discoloration and degradation of the leachate. The findings demonstrated the potential for the use of microorganisms from landfill leachate as bioremediation tools.