Increase of the Trametes versicolor efficiency in bioremediation process for diclofenac biodegradation in aquatic environments

Résumé

Diclofenac (DCF) is a non-steroidal anti-inflammatory drug and, as pollutant, it represents a persistent residue hazard to health and to the environment. Trametes versicolor was previously selected for its ability in diclofenac biodegradation (up to 20%) during cultivation in submerged system under aerobic conditions at an initial DCF concentration of 10 mg L-1. The influence of some factors such as nitrogen sources glucose, MnSO4·H2O, CuSO4·5H2O, inoculum level, initial DCF concentration and incubation time, upon the biodegradation potential was examined by Plackett-Burman analysis. The parameters significantly influencing the DCF biotransformation were found to be yeast extract, glucose, CuSO4·5H2O and inoculum level. In these optimum conditions, the DCF biotransformation yield was 80%. This result was 60% superior in comparison with the medium without optimization. Analysis of variance exhibited a high coefficient of determination (R2) value of 0.9987 and ensured that the polynomial model with the experimental data was a satisfactory one. Optimal conditions obtained in this work led to a solid foundation for further use of Trametes versicolor in biotreatment of high strength
DCF pollutant effluents in water wastes.