Valorizing fungal diversity for the degradation of fluoroquinolones

• Published in: Heliyon 2024-05, Vol.10 (10), p.e30611-e30611, Article e30611
• Main Authors: Akrout, Imen, Staita, Karima, Zouari-Mechichi, Hèla, Ghariani, Bouthaina, Khmaissa, Marwa, Navarro, David, Doan, Annick, Albert, Quentin, Faulds, Craig, Sciara, Giuliano, Record, Eric, Mechichi, Tahar
• Format: Article
• Language: English
• Subjects: Cytochrome P450; Environmental Sciences; Fluoroquinolones; Laccase; Ligninolytic fungi; Peroxidase
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2024.e30611

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. [Display omitted] •Ligninolytic fungi emerge as promising candidates for the biotransformation of fluoroquinolones.•Among the tested fungi, B. adusta and P. spadiceum were the most efficient in fluoroquinolone concentration reduction.•Total reduction of the antibiotic concentration does not necessarily translate a reduction in antimicrobial activity.•Evidence for the involvement of cytochrome P450 system and adsorption process in fluoroquinolone transformation by B. adusta.