Susceptibility of clinical isolates of Candida to photodynamic effects of curcumin
Article first published online: 17 OCT 2011
Copyright © 2011 Wiley Periodicals, Inc.
Lasers in Surgery and Medicine
Volume 43, Issue 9, pages 927–934, November 2011
How to Cite
Dovigo, L. N., Pavarina, A. C., Carmello, J. C., Machado, A. L., Brunetti, I. L. and Bagnato, V. S. (2011), Susceptibility of clinical isolates of Candida to photodynamic effects of curcumin. Lasers Surg. Med., 43: 927–934. doi: 10.1002/lsm.21110
- Issue published online: 17 OCT 2011
- Article first published online: 17 OCT 2011
- Manuscript Accepted: 5 JUL 2011
- Fundação de Amparo a Pesquisa do Estado de São Paulo. Grant Number: FAPESP 2008/03994-9; 2008/00601-6
- Candida albicans;
- Candida glabrata;
- Candida tropicalis;
- photodynamic therapy;
Background and Objective
The resistance of Candida species to antifungals represents a major challenge for therapeutic and prophylactic strategies. This study evaluated photodynamic therapy (PDT) mediated by Curcumin (CUR) against clinical isolates of C. albicans, C. tropicalis, and C. glabrata, both in planktonic and biofilm forms.
Study Design/Materials and Methods
Suspensions of Candida were treated with three CUR concentrations and exposed to four LED fluences. The protocol that showed the best outcomes for inactivation of the planktonic phase was selected to be evaluated against Candida biofilms. In addition, two higher CUR concentrations were tested. The metabolic activity of biofilms was evaluated by means of XTT reduction assay and the biofilm biomass was evaluated using crystal violet (CV) staining assay. Data were analyzed in a mixed model nested ANOVA, Wilcoxon's nonparametric tests, and the Kruskal–Wallis test (α = 5%).
The use of CUR in association with light was able to promote a significant antifungal effect against the planktonic form of the yeasts. When using 40 µM of CUR, the metabolic activity of C. albicans, C. glabrata, and C. tropicalis biofilms was reduced by 85%, 85%, and 73%, respectively, at 18 J/cm2. CUR-mediated PDT also decreased the biofilm biomass of all species evaluated. In addition, CV staining showed that C. albicans isolates were strong biofilm-forming strains, when compared with C. glabrata and C. tropicalis isolates.
The results from the present investigation showed that low CUR concentrations can be highly effective for inactivating Candida isolates when associated with light excitation. Lasers Surg. Med. 43:927-934, 2011. © 2011 Wiley Periodicals, Inc.