文摘
Phenolic and cyanide compounds, which frequently appear mixed in several industrial effluents, are difficult to be biodegraded under certain conditions. In this work, salicylic acid (SA) and thiocyanate (SCN−) were selected as model pollutants of these two families and experiments of biodegradation with specific microorganisms were developed. It was found that the best well-known bacteria able to biodegrade each one of these pollutants, Pseudomonas putida for SA and Paracoccus thiocyanatus for SCN−, do not biodegrade the other one. Therefore, the co-culture was required, producing interesting interaction phenomena. When both pollutants were simultaneously biodegraded, a commensalism effect was observed improving SCN− removal. Experimental data for SCN− and SA removals were successfully fitted to zero reaction kinetic orders, with induction time in the case of SCN−, and substrate dependences were fitted to Tessier models. A flow cytometry method was developed and employed to obtain the evolution of the viable, damaged and dead cells for different substrate concentration and the degree of agglomeration in the co-culture experiments.