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 wellknown
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.
