Tetradecyltrimethylammonium degradation by free and immobilized Pseudomonas putida

BERGERO, MF; ESTEVEZ, G; LIFFOURRENA AS; LUCCHESI GI

San juan

Congreso; Segunda Reunión Conjunta de Sociedades de Biología de la República Argentina; 2011

Tetradecyltrimethylammonium bromide (TTAB) degradation by immobilized P. putida A ATCC 12633 and free cells suspension was studied under controlled conditions. For suspended cells culture, exponentially growing cells were added to Erlenmeyer flasks containing M9 medium. For immobilized cells, 20mM HCl-Tris pH 7.4 plus KCl 44mM, NaCl 85mM, was used. In both conditions, TTAB 50, 100 and 170 mg l-1 was added. The degradation process was carried out at 30ºC on a rotary shaker at 100 rpm. Samples from the culture were withdrawn under sterile conditions at different incubation period for the analysis of residual TTAB and trimethylamine (TMA), an intermediate product in the degradation of TTAB. The free cells degraded 28 mg l-1 of TTAB after 48 h of incubation from an initial 50 mg l-1 TTAB and they lost their degrading activity when the initial concentration was increased to 100 mg l-1. The alginate-immobilized cells degraded 117 mg l-1 TTAB after 24 h of incubation from an initial 150 mg l-1 of TTAB. An inhibitory effect of the intermediary TMA from TTAB degradation was observed in free cells but it was not presented in the immobilized system. This effect was countered after additions of AlCl3 0.1 mM. Overall, these results revealed that the immobilized cell systems are more efficient than suspended cells for TTAB degradation.