Antibacterial and antifungal activity of curcumin and methylene blue associated with laser on bacterial and fungal strains

Objective: To analyze the effect of methylene blue and 10% curcumin in fungi and bacteria through an in vitro study using photodynamic therapy (PDT). Methods: Curcumin and methylene blue were photosensitized by a Photon Lase III laser applied for 90 s in a dark environment within a laminar flow chamber. Enterococcus faecalis and Candida albicans strains were cultured and standardized. Then, a minimum inhibitory concentration (MIC) assay was conducted for these photosensitizers, with concentration variations and incubation to evaluate their antimicrobial activity. Results: With PDT, Curcumin had significant antibacterial activity against E. faecalis (MIC = 250 µg/mL). In contrast, methylene blue had antibacterial activity against E. faecalis (MIC < 12.5 µg/mL with PDT) and antifungal activity against C. albicans (MIC