The Efficacy of Photodynamic Inactivation of the Diode Laser in Inactivation of the Candida albicans Biofilms With Exogenous Photosensitizer of Papaya Leaf Chlorophyll

Abstract Introduction: N Photodynamic inactivation has been developed to kill pathogenic microbes. In addition, some techniques have been introduced to minimize the biofilm resistance to antifungal properties in inhibiting cell growth. The principle of photodynamic inactivation different to antifungal drugs therapy which is resistant to biofilms. The presence of reactive oxygen species (ROS) that generating in photodynamic inactivation mechanisms can be damaging of biofilm cells and the principle of light transmission that could be penetrating in matrix layers of extracellular polymeric substance (EPS) until reaching the target cells at the base layers of biofilm. The present work aims to explore the potential of chlorophyll extract of papaya leaf as an exogenous photosensitizer to kill the Candida albicans biofilms after being activated by the laser. The potential of chlorophyll photosensitizer was evaluated based on the efficacy of inactivation C. albicans biofilm cell through a cell viability test and an organic compound test.Methods: The treatment of photoinactivation was administered to ۱۲ groups of C. albicans biofilm for four days using the ۴۴۵ nm laser and the ۶۵۰ nm laser. The ۴۴۵ nm and ۶۵۰ nm lasers activated the chlorophyll extract of the papaya leaf (۰.۵ mg/L) at the same energy density. The energy density variation was determined as ۵, ۱۰, ۲۰, ۳۰ and ۴۰ J/cm۲ with the duration of exposure of each laser adjusted to the absorbance percentage of chlorophyll extract of the papaya leaf.Results: The absorbance percentage of chlorophyll extracts of the papaya leaf on wavelengths of ۶۵۰ nm and ۴۴۵ nm respectively were ۲۲.۲۶% and ۶۰.۲۹%, respectively. The most effective treated group was a group of the laser with the addition of chlorophyll, done by the ۶۵۰ nm lasers with inactivation about ۳۲% (P = ۰.۰۰۱), while the ۴۴۵ nm lasers only ۲۵% (P = ۰.۰۶۱). The maximum malondialdehyde levels by treatment of the laser ۶۵۰ nm were (۰.۰۴۶±۰.۰۰۴) nmol/mg.Conclusion: The use of chlorophyll extract of the papaya leaf as a photosensitizer, resulted in the maximum spectrum of absorption at ۴۱۴ nm and ۶۶۸ nm, which produced a maximum reduction effect after photoinactivation up to ۳۲% (with chlorophyll) and ۲۵% (without chlorophyll). The utilization of chlorophyll extract of the papaya leaf would increase the antifungal effects with the activation by the diode laser in the biofilm of C. albicans.Keywords: Candida albicans biofilms; Chlorophyll extract; Photoinactivation Keywords: Candida albicans biofilms Chlorophyll extract Photoinactivation.