Atividade e dinâmica populacional de um consórcio bacteriano durante biodegradação de óleo diesel no solo

• Autor(a) principal: Leal, Patrícia Lopes
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1548
• topic: Bactérias; Consórcio; Biodegradação; Hidrocarbonetos; Óleo diesel; Solo; Bacterial; Consortium; Biodegradation; Hydrocarbons; Diesel oil; Soil; CNPQ::CIENCIAS AGRARIAS

Bioremediation of environments contaminated with petroleum hydrocarbons is a biotechnological process that usually involves the use of microorganisms capable of metabolizing hydrocarbons and convert them into inert substances (CO2 and water). Bioremediation tends to occur naturally and can be accelerated by the optimization of environmental factors (biostimulation) and or the introduction of microorganisms capable of degrading the contaminants (bioaugmentation). Some factors affect the efficiency of biodegradation of contaminants such as the metabolic capacity of microorganisms to degrade the contaminant, environmental conditions and the bioavailability of the contaminant. In bioaugmentation, the use of different microbial species or strains (consortium) to the occurrence of population dynamics that lead to a succession of attacks on compounds, pollutants, providing efficient degradation of the same quantity and quality when compared to pure cultures of microorganisms. This study aimed to evaluate metabolic activity of bacterial strains Acinetobacter baumannii LBBMA 04, Pseudomonas aeruginosa LBBMA 58, Ochrobactrum anthropi LBBMA 88b, Acinetobacter baumannii LBBMA ES11, Bacillus subtilis LBBMA 155 in pure cultures and consortium in the biodegradation of hydrocarbons alkanes, in culture medium with diesel oil, to analyze the pattern of fluctuations in microbial populations and the pattern of consumption of total petroleum hydrocarbons (THP), in soil contaminated with diesel oil in response to the factors temperature, humidity and nutrient availability, and to evaluate the effect of successive soil contamination with diesel oil in the population dynamics of members of a bacterial consortium and the sequence of degradation of total petroleum hydrocarbons (TPH). The bacterial consortium was more efficient in the degradation of hydrocarbons nonane, decane and undecane present in the culture medium when compared to pure cultures. The degradation of these compounds by the consortium was over 99% after 30 days of incubation. Environmental factors influencing the degradation of HTP in soil contaminated with diesel oil, the best condition found was 35°C, 125:10:1 and 60% for temperature, the C:N:P and moisture content, respectively. Successive soil contamination with diesel oil promoted changes in population structure of the bacterialconsortium and the sequence of grading total petroleum hydrocarbons. However the bacterial consortium was presented as potential candidate for use in operations bioremediation of soils contaminated with diesel oil. After 60 days, the bacterial consortium degraded approximately 55% of TPH soil after repeated contamination with diesel oil.