Kinetics model for growth of Pseudomonas putida F1 during benzene, toluene and phenol biodegradation

The effect of adaptation of Pseudomonas putida F1 ATCC 700007 (Pp F1) to the biodegradation of benzene (B), toluene (T) and phenol (P) was studied. The adaptation of microorganism to BTP decreased the biodegradation time from 24 to 6 It for benzene (90 mg/1) and toluene (90 mg/1), and from 90 to 18 It for phenol (50 mg/1). Andrews kinetics model for single substrate was solved to obtain maximum specific growth rates, half saturation and substrate inhibition constant. Cell growth using toluene (mu(max.T) = 0.61) and benzene (mu(max.B) = 0.62) as carbon sources were better and faster than the growth in phenol (mu(max.P) = 0.051). For the substrate mixtures, a sum kinetics model was used and the interaction parameters were determined. These models provided an excellent prediction of the growth kinetics and the interactions between these substrates. Toluene inhibited the utilization of benzene (I-T, B = 5.16) much more than benzene inhibits the utilization of toluene (I-B.T = 0.49). Benzene (I-B.P = 0.27) and toluene (I-T.P= 0.14) enhance the biodegradation of phenol, and phenol inhibits the biodegradation of benzene (I-P.B = 1.08) and toluene (I-P.T = 1.03). (C) 2003 Elsevier Ltd. All rights reserved.