Due to widespread overuse, pharmaceutical compounds, such as antibiotics, are becoming increasingly prevalent in greater concentrations in aquatic ecosystems. In this study, we investigated the capacity of the white-rot fungus, Coriolopsis gallica (a high-laccase-producing fungus), to biodegrade ampicillin under different cultivation conditions. The biodegradation of the antibiotic was confirmed using high-performance liquid chromatography, and its antibacterial activity was evaluated using the bacterial growth inhibition agar well diffusion method, with Escherichia coli as an ampicillin-sensitive test strain. C. gallica successfully eliminated ampicillin (50 mg L⁻¹) after 6 days of incubation in a liquid medium. The best results were achieved with a 9-day-old fungal culture, which treated a high concentration (500 mg L⁻¹) of ampicillin within 3 days. This higher antibiotic removal rate was concomitant with the maximum laccase production in the culture supernatant. Meanwhile, four consecutive doses of 500 mg L⁻¹ of ampicillin were removed by the same fungal culture within 24 days. After that, the fungus failed to remove the antibiotic. The measurement of the ligninolytic enzyme activity showed that C. gallica laccase might participate in the bioremediation of ampicillin.

Continued widespread use of antibiotics, especially fluoroquinolones, raises environmental concerns, as its driving bacterial resistance and disrupts microbial ecosystems. Here we investigate the biodegradation of ten fluoroquinolone antibiotics (six for medical use and four for veterinary use) by ligninolytic fungi, including Trametes versicolor, Bjerkandera adusta, Porosterum spadiceum, Irpex lacteus, Pleuroteus ostreatus, Phanerochaete chrysosporium, Pycnoporus cinnabarinus, Ganoderma lucidum, and Gloeophyllum trabeum. The results show significant variations between strains in the efficiency of antibiotic transformation. B. adusta and P. spadiceum were the fungi that most efficiently reduced antibiotic concentrations and were able to totally degrade eight and six antibiotics, respectively, within a 15-day period. T. versicolor and P. ostreatus also showed the ability to effectively degrade antibiotics. Specifically, T. versicolor degraded six out of the ten fluoroquinolone antibiotics by more than 70 %, while P. ostreatus degraded the tested antibiotics between 43 % and 100 %. The remaining antibiotic activity did not always correlate with a reduction in antibiotic concentrations, which points to the presence of post-transformation antimicrobial metabolites. This study also explores the potential mechanisms used by these fungi to remove selected models of fluroquinolones via enzymatic routes, such as oxidation by laccases, heme-peroxidases, and cytochrome P450, or via adsorption on fungal biomass.

The over use of pharmaceutical compounds, essentially antibiotics, led to an increase of their concentrations in aquatic ecosystems. In this study, the white-rot fungus Coriolopsis gallica (high-laccase-producing fungus) was investigated for the biodegradation of ampicillin (AMP) under different cultivation conditions. The biotransformation of the antibiotic was confirmed by means of high-performance liquid chromatography (HPLC), and the antibacterial activity was evaluated via the bacterial growth inhibition agar well diffusion method using Escherichia coli as an ampicillin-sensitive test strain. The results showed that AMP (50 mg L-1) was totally removed by C. gallica after 6 days of incubation in a liquid medium. The antibiotic removal rate was maximal with a fungal culture aged 9 days. Such a culture achieved the removal of a higher concentration of up to 500 mg L-1 of ampicillin in 3 days. This higher antibiotic removal rate was concomitant with the maximal laccase production in culture supernatant. In addition, four consecutive doses of 500 mg L-1 of ampicillin were transformed by the same fungal culture in 24 days. After that, the fungus was unable to remove the antibiotic. The measurement of ligninolytic enzyme activity showed that laccase of C. gallica might participate in the biotransformation of AMP.

Background/Objectives: Wastewaters containing antibiotics pose risks to human health and soil ecosystems. In this study, the white-rot fungus Coriolopsis gallica (a basidiomycete exhibiting high laccase production) was used for the biotransformation of three antibiotics (50 mg L⁻¹): tetracycline, chloramphenicol, and sulfanilamide. Methods: The biotransformation process was investigated in liquid and solid media using high-performance liquid chromatography (HPLC) and the bacterial growth inhibition agar well diffusion method, respectively. Results: Among the three antibiotics tested, tetracycline showed the highest biotransformation efficiency, achieving a 100% removal rate in the liquid medium and a 100% decrease in the growth inhibition of Escherichia coli in the solid medium. Chloramphenicol and sulfanilamide were partially removed (20% and 16%, respectively) after 12 days of treatment in more than one step without the loss of their antibacterial activities. The presence of these antibiotics in the culture medium of C. gallica enhanced laccase activity, indicating that this ligninolytic enzyme might participate in the biotransformation process. Conclusions: Thus, the results reported in this article extend our knowledge of the catalytic potential of C. gallica and give further perspectives for its application in the biodegradation of antibiotics. To the best of our knowledge, this is the first study wherein C. gallica was used for the treatment of tetracycline, chloramphenicol, and sulfanilamide.

Antibiotics play a crucial role in human and animal medical healthcare, but widespread use and overuse of antibiotics poses alarming health and environmental issues. Fluoroquinolones constitute a class of antibiotics that has already become ubiquitous in the environment, and their increasing use and high persistence prompt growing concern. Here we investigated a fungal secretome prepared from the white-rot fungus Coriolopsis gallica, which is able to effectively degrade the environmentally persistent fluoroquinolone, levofloxacin. We tested various physical–chemical factors such as concentrations of 1-hydroxybenzotriazol (HBT), of enzyme, and of antibiotic, and pH and temperature of the reaction for biotransformation of the antibiotic. We compared the free with the immobilized Coriolopsis gallica secretome proteins, and analyzed the collective reaction products for residual activity against E. coli (growth inhibition test). We also performed HPLC analysis. The results show that treatment with the free secretome yielded a highest removal efficiency of 50 mg L⁻¹ levofloxacin in the presence of 2.5 mM HBT, whereas the immobilized secretome was only able to degrade 10 mg L⁻¹ levofloxacin with the same concentration of mediator, but presenting the advantage of being reusable.