Comparison of the Biodegradation Capacity of Two Fungal Strains Toward a Mixture of Phenol and Cresol by Mathematical Modeling

The examined strains of Aspergillus awamori NRRL 3112 and Trametes versicolor 1 were cultured in a culture medium containing phenol, p-cresol and a mixture of them as single carbon substrates. Both strains were able to utilize both examined compounds. The results showed that the strain of Trametes versicolor 1 degraded p-cresol much faster than the strain Aspergillus awamori NRRL 3112. In the experiments on degradation of the mixture of phenol and p-cresol by both strains, complete carbon utilization was also observed. The influence of the mixed substrate on the growth of microbial cultures was studied. A positive influence of phenol on the degradation of cresol by Aspergillus awamori NRRL 3112 and Trametes versicolor 1 was observed. SKIP models (Sum kinetics with interaction parameters) expressing the total kinetics of the degradation of a mixture of phenol/p-cresol in Aspergillus awamori NRRL 3112 and Trametes versicolor 1 were created. The obtained values of the interaction coefficients in the model (Iph/cr and Icr/ph) corresponded to the influence exerted by each of the investigated mixed compounds on the development and degradation capacities of both fungal strains.