Effects of temperature, pH, and salinity on the growth kinetics of Pseudomonas sp. NB-1, a newly isolated cold-tolerant, alkali-resistant, and high-efficiency nitrobenzene-degrading bacterium

Strain NB-1, which can efficiently degrade nitrobenzene, was identified as Pseudomonas frederiksbergensis. NB-1 was resistant to cold and alkali with the widest temperature (4-35 degrees C) and pH (5-11) adaptive range, compared with other reported nitrobenzene-degrading microorganisms. Based on the Haldane-Andrews model, the real maximum specific growth rate mu(m)', specific affinity a(A), and inhibition coefficient K-i were used in response surface methodology (RSM) simultaneously for the first time to guide NB-1 to treat nitrobenzene wastewater. According to the RSM model, the environmental factors (temperature, pH, salinity) corresponding to the optimal values of mu(m)', a(A), and K-i were determined. By comparing the specific growth rates corresponding to the optimal values of mu(m)', a(A), and K-i, respectively, the optimum growth conditions of NB-1 were determined under different nitrobenzene concentrations. The study of mu(m)', a(A), and K-i by RSM provided a new approach for a more accurate optimization of biological wastewater treatment conditions. [GRAPHICS]