Photodynamic and Sonophotodynamic inactivation of Rhyzopus oryzae biofilm

Mucormycosis is a highly aggressive fungal disease with high mortality. Traditional treatment involves high doses of antifungal agents and surgical resection, but outcomes remain poor. Photodynamic inactivation (PDI) and Sono-photodynamic inactivation (SPDI) are emerging as promising alternatives or complements to conventional therapies. This study evaluated the antimicrobial effects on Rhizopus oryzae biofilms using PDI and SPDI protocols with Photodithazine (PDZ) as the photosensitizer. Amphotericin B (AMB) was used as a comparative antifungal. Variables included PDZ concentration, associations with surfactants and potassium iodide (KI), and fluence at 660 nm. Complete inactivation was not achieved in any protocol, but PDI and SPDI showed potential as complementary tools for controlling Rhizopus oryzae biofilms. PDI and SPDI reduced viable cells, degraded fungal biomass, and reduced metabolism. However, biofilm eradication was not achieved, highlighting the need for combination treatments with antifungal drugs.