Diacetylcurcumin: a new photosensitizer for antimicrobial photodynamic therapy in Streptococcus mutans biofilms

Abstract

This study evaluated the effect of antimicrobial photodynamic therapy (aPDT) on S. mutans using diacetylcurcumin (DAC) and verified DAC toxicity. In vitro, S. mutans biofilms were exposed to curcumin (CUR) and DAC and were light-irradiated. Biofilms were collected, plated and incubated for colony counts. DAC and CUR toxicity assays were conducted with Human Gingival Fibroblast cells (HGF). In vivo, G. mellonella larvae were injected with S. mutans and treated with DAC, CUR and aPDT. The hemolymph was plated and incubated for colony counts. Significant reductions were observed when DAC and CUR alone were used and when aPDT was applied. HGF assays demonstrated no differences in cell viability for most groups. DAC and CUR reduced the S. mutans load in G. mellonella larvae both alone and with aPDT. Systematic toxicity assays on G. mellonella demonstrated no effect of DAC and CUR or aPDT on the survival curve.

Keywords:

• Dental caries
• photodynamic therapy
• biofilms
• Streptococcus mutans
• Galleria mellonella
• diacetylcurcumin

Acknowledgments

The authors would like to thank Mr Antonio Correa for his support with the English version of the manuscript.

Disclosure statement

The authors declare no proprietary or financial interest in any products mentioned in this manuscript.

Funding details

The authors would like to acknowledge the financial support obtained from the Project FOP / Unicamp and State University of Maringá, approved by Edict No. 71/2013 of the National Program for Academic Cooperation (PROCAD) - of the Coordination for the Improvement of Higher Education Personnel (CAPES).