glabrata biofilms were not PIT-dependent and showed higher absorbance values commonly found under most of the experimental conditions presented. Regarding C. dubliniensis biofilms results, after 4 min of irradiation, there was no clear tendency to be PIT-dependent, showing a different behaviour from

C. albicans. A recent study also found that C. dubliniensis tended to be more resistant to PDT effects when compared to C. albicans. 55 The authors showed that higher concentrations of erythrosine were necessary to achieve the same microbial reduction observed for C. albicans and only a 0.21 log10 reduction on CFU/mL of C. dubliniensis biofilms where obtained when exposed to PDT mediated by 400 μM erythrosine and a green LED. 55 Therefore, more studies are necessary to identify biological reasons of different response to PDT among different species of Candida. Cur-mediated PDT was shown to be effective Gemcitabine in vitro against Candida biofilms. Reductions of 94%, 89% and 85% in cell viabilities were observed for C. albicans, C. glabrata and C. dubliniensis, respectively. Photosensitisers may need a longer time to penetrate into the depth of the biofilms 12 to achieve intimate contact with the specimens in order to obtain more

effective action. The 20 min PIT associated with 40 μM Cur resulted in the highest reductions in cell viability. Whilst it is not suggested A-1210477 concentration that PDT will replace conventional therapy, improvements may be obtained using the photodynamic approach in the clinical treatment of local infection,30 and Cur-mediated PDT may exhibit benefits in the treatment of oral candidiasis of immunocompromised patients and/or in cases of long-term use of medications, in Farnesyltransferase which the emergence of resistant strains is likely to occur. Based on the experimental conditions of this study and in accordance with the methodology used, it was possible to conclude that PDT with the association of Cur and blue LED light was effective in decreasing cell viabilities of the three Candida

species evaluated. For the planktonic cultures, photoinactivation was concentration-dependent, but not PIT-dependent. The further combination of 20 μM Cur and LED light at 5.28 J/cm2 output promoted complete inactivation of the suspensions after 5, 10 and 20 min time intervals of PIT. On the other hand, Cur-mediated PDT was shown to be effective against Candida biofilms, with reductions of 94%, 89% and 85% in the cell viabilities of C. albicans, C. glabrata and C. dubliniensis, respectively. As observed in CLSM images, Cur needed a longer time to show a more intense brightness deeper in the biofilm, and, in this way, achieve intimate contact with the organisms and obtain more effective action. Thus, the highest reductions in cell viability for the biofilm cultures were achieved after associating 40 μM Cur with 20 min of PIT. CAPES/DS (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior). None to declare.