Comparison of the photodynamic fungicidal efficacy of methylene blue, toluidine blue, malachite green and low-power laser irradiation alone against Candida albicans.
This study was to evaluate specific effects of photodynamic therapy (energy density 15.8 J/cm(2), 26.3 J/cm(2) and 39.5 J/cm(2)) using methylene blue, toluidine blue and malachite green as photosensitizers and low-power laser irradiation on the viability of Candida albicans. Suspensions of C. albicans containing 10(6) cells/ml were standardized in a spectrophotometer. For each dye, 120 assays, divided into four groups according to the following experimental conditions, were carried out: laser irradiation in the presence of the photosensitizer; laser irradiation only; treatment with the photosensitizer only; no exposure to laser light or photosensitizer. Next, serial dilutions were prepared and seeded onto Sabouraud dextrose agar for the determination of the number of colony-forming units per milliliter (CFU/ml). The results were subjected to analysis of variance and the Tukey test (P < 0.05). Photodynamic therapy using the photosensitizers tested was effective in reducing the number of C. albicans.. The number of CFU/ml was reduced by between 0.54 log(10) and 3.07 log(10) and depended on the laser energy density used. Toluidine blue, methylene blue and malachite green were effective photosensitizers in antimicrobial photodynamic therapy against C. albicans, as was low-power laser irradiation alone.
Souza
Rodrigo C
RC
Department of Biosciences and Oral Diagnosis, School of Dentistry of São José dos Campos, São Paulo State University (UNESP), Francisco José Longo 777, São Dimas, São José dos Campos 12245-000, SP, Brazil.
Junqueira
Juliana Campos
JC
Rossoni
Rodnei D
RD
Pereira
Cristiane A
CA
Munin
Egberto
E
Jorge
Antonio O C
AO
D000935:Antifungal Agents / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects* / Q000472:pathogenicity / Q000528:radiation effects*; D002177:Candidiasis / Q000188:drug therapy / Q000532:radiotherapy; D006801:Humans; D066298:In Vitro Techniques; D028022:Low-Level Light Therapy; D008751:Methylene Blue / Q000494:pharmacology; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000494:pharmacology*; D012394:Rosaniline Dyes / Q000494:pharmacology; D014048:Tolonium Chloride / Q000494:pharmacology
D000935:Antifungal Agents; D017319:Photosensitizing Agents; D012394:Rosaniline Dyes; C005095:malachite green; D014048:Tolonium Chloride; D008751:Methylene Blue