Behavior of an atrazine degrading bacterial consortium in shake flask and bioreactor culture systems

CALABRO, A; BUSTO, V.; CUADRADO, VL; RODRIGUEZ TALOU , J; GIULIETTI, AM

San Miguel de Tucuman

Congreso; XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009

SAIB

Shake-flasks have been used for decades as simple bioreactors to allow the development of effective growth media for cellular growth processes. On the other hand, stirred tank bioreactors are widely implemented in the industrial production to obtain high cell biomass or desire products. The transfer of shake-flask derived processes to standard stirred tank bioreactors is typically problematic since growth and yields fall significantly at this stage. Bioremediation is a well known tool used to degrade or transform contaminants. To conduce an efficient bioremediation process it is necessary a bioaugmentation phase in order to produce an inoculum with high biomass concentration. In this work we studied the performance of an atrazine degrading bacterial consortium isolated from soils of the Argentinean Humid Pampa in both, Erlenmeyer flasks and stirred tank bioreactors. Shake flask experiments were carried out in 250 ml erlenmeyers utilizing previously optimized conditions. Alternatively, a 1.5 L stirred tank bioreactor operated at the same conditions as in shake flask was employed. The evolution of biomass production and media pH showed similar behavior in both culture systems. Complete degradation of atrazine was observed in all experiments. Results show that the transfer of erlenmeyer optimized conditions to bioreactor was effective and can be use in future bioaugmentation processes.