Today, more than 3,000 pharmaceutical and personal care products (PPCPs) are used and released into the environment at low doses but they are barely degraded in wastewater treatment plants. One of the potential alternatives to effectively degrade PPCPs is based on the use of white-rot fungi (WRF) and involves the oxidative action of extracellular fungal enzymes. The aim of this work is to study the potential ability of three WRF strains, an anamorph species of Bjerkandera sp. R1, Bjerkandera adusta and Phanerochaete chrysosporium, to degrade PPCPs belonging to different therapeutic groups: anti-depressants (citalopram and fluoxetine), antibiotics (sulfamethoxazole), anti-inflammatory drugs (diclofenac, ibuprofen and naproxen), anti-epileptics (carbamazepine), tranquilizers (diazepam) and fragrances (celestolide, galaxolide and tonalide). The results reported complete degradation of all the PPCPs except for fluoxetine and diazepam, which were partially removed in percentages from 23 to 57%. In the case of fragrances, these compounds were neither detected in the fungal cultures nor in the abiotic controls, indicating the possibility of volatilization during the experiment.

White-rot fungi are a group of microorganisms capable of degrading xenobiotic compounds, such as polycyclic aromatic hydrocarbons or synthetic dyes, by means of the action of extracellular oxidative enzymes secreted during secondary metabolism. In this study, the transformation of three anti-inflammatory drugs: diclofenac, ibuprofen and naproxen were carried out by pellets of Phanerochaete chrysosporium in fed-batch bioreactors operating under continuous air supply or periodic pulsation of oxygen. The performance of the fungal reactors was steady over a 30-day treatment and the effect of oxygen pulses on the pellet morphology was evidenced. Complete elimination of diclofenac was achieved in the aerated and the oxygenated reactors, even with a fast oxidation rate in the presence of oxygen (77% after 2 h), reaching a total removal after 23 h. In the case of ibuprofen, this compound was completely oxidized under air and oxygen supply. Finally, naproxen was oxidized in the range of 77 up to 99% under both aeration conditions. These findings demonstrate that the oxidative capability of this microorganism for the anti-inflammatory drugs is not restricted to an oxygen environment, as generally accepted, since the fungal reactor was able to remove these compounds under aerated and oxygenated conditions. This result is very interesting in terms of developing viable reactors for the oxidation of target compounds as the cost of aeration can be significantly reduced.

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