The Use of Chitosan to Enhance Photodynamic Inactivation against Candida albicans and Its Drug-Resistant Clinical Isolates

International Journal of Molecular Sciences

Hsiung-Fei Chien³  Chueh-Pin Chen¹  Yee-Chun Chen⁴  Po-Han Chang¹  Tsuimin Tsai² 

[1] Department of Biochemical Science and Technology, National Taiwan University, Taipei 106, Taiwan; E-Mails:;Graduate Institute of Biomedical Materials and Tissue Engineering, College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan; E-Mail:;Department of Surgery, National Taiwan University College of Medicine, Taipei 100, Taiwan; E-Mail:;Department of Internal Medicine, National Taiwan University College of Medicine, Taipei 100, Taiwan; E-Mail:

关键词: chitosan;    Candida;    antimicrobial;    photodynamic inactivation;   

DOI  :  10.3390/ijms14047445

来源: mdpi

【 摘 要 】

Drug-resistant Candida infection is a major health concern among immunocompromised patients. Antimicrobial photodynamic inactivation (PDI) was introduced as an alternative treatment for local infections. Although Candida (C.) has demonstrated susceptibility to PDI, high doses of photosensitizer (PS) and light energy are required, which may be harmful to eukaryotic human cells. This study explores the capacity of chitosan, a polycationic biopolymer, to increase the efficacy of PDI against C. albicans, as well as fluconazole-resistant clinical isolates in planktonic or biofilm states. Chitosan was shown to effectively augment the effect of PDI mediated by toluidine blue O (TBO) against C. albicans that were incubated with chitosan for 30 min following PDI. Chitosan at concentrations as low as 0.25% eradicated C. albicans; however, without PDI treatment, chitosan alone did not demonstrate significant antimicrobial activity within the 30 min of incubation. These results suggest that chitosan only augmented the fungicidal effect after the cells had been damaged by PDI. Increasing the dosage of chitosan or prolonging the incubation time allowed a reduction in the PDI condition required to completely eradicate C. albicans. These results clearly indicate that combining chitosan with PDI is a promising antimicrobial approach to treat infectious diseases.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland