Fungal derived dye as potential photosensitizer for antimicrobial photodynamic therapy

Author(s)

de Lima, Isabelle Almeida ; Lima, Caio de Azevedo ; de Annunzio, Sarah Raquel ; de Oliveira, Fernanda ; da Silva, Silvio Silverio ; Fontana, Carla Raquel ; Santos-Ebinuma, Valeria de Carvalho

• Document type: Journal article
• Source: JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY; v. 264, p. 9-pg., 2025-03-01.

Abstract

Photodynamic therapy (PDT) combines light with a photosensitizing agent to target and destroy abnormal cells or pathogens, offering a non-invasive and precise approach. Applying microbial dyes in PDT presents a great opportunity because these compounds may absorb specific wavelengths of light, generating reactive oxygen species (ROS) that induce oxidative stress, leading to cell or microbial death. This study evaluated the extract of Talaromyces amestolkiae containing azaphilone red dyes obtained from cultivation process as photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT). Initially the crude extract was obtained in incubator shaker varying the culture media composition. Following, the crude extract containing the red dyes exhibited nontoxicity in dark conditions across all concentrations tested. PDT experiments with different amounts of the crude extract at a light dose of 80 J.cm-2 and upon irradiation at 460 nm was studied. A complete reduction of Escherichia coli and approximately 2 log10 reductions of Staphylococcus aureus, Cutibacterium acnes and Enterococcus faecalis was achieved using 25 % (v.v-1) of the crude extract while 50 % (v.v-1) of the crude extract led to a complete reduction of both E. coli and S. aureus, and around 5 log10 reductions of C. acnes and E. faecalis. Importantly, minimal photodegradation of the PS occurred during irradiation across all concentrations studied. These findings highlight the potential of T. amestolkiae-derived red dyes extract for use in aPDT, demonstrating non-toxicity in the absence of light, good aqueous solubility, high photostability, and strong microbial reduction capabilities under specific light conditions. (AU)

• FAPESP's process: 21/06686-8 - Biotechnological process for the development of natural colorants from microbial sources for industrial application: phase II
• Grantee: Valéria de Carvalho Santos Ebinuma
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Young Investigators Grants - Phase 2
• FAPESP's process: 23/01368-3 - Stabilization and encapsulation of natural colorants and application in the development of packaging and cosmetics
• Grantee: Valéria de Carvalho Santos Ebinuma
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/09088-1 - Assessment of photodynamic therapy against polymicrobial acne biofilms: a preclinical study
• Grantee: Sarah Raquel de Annunzio
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 22/14603-8 - Untargeted metabolomics based on molecular networking aiming the valorization of the fungi colored compounds
• Grantee: Fernanda de Oliveira
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• FAPESP's process: 18/23015-7 - Antimicrobial photodynamic therapy by continuous and switched mode irradiation against Enterococcus faecalis and Cutibacterium acnes
• Grantee: Carla Raquel Fontana
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/09175-4 - BIOREFINERY AS A PLATFORM FOR THE PRODUCTION OF FUNGAL COLORANTS
• Grantee: Fernanda de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/04294-5 - Production of natural colorants by Talaromyces amestolkiae and evaluation of their potential as a photosensitizer for antimicrobial photodynamic therapy
• Grantee: Isabelle Almeida de Lima
• Support Opportunities: Scholarships in Brazil - Scientific Initiation