Photoinactivation of microorganisms using bacteriochlorins as photosensitizers

• Published in: Brazilian journal of microbiology 2024-06, Vol.55 (2), p.1139-1150
• Main Authors: da Cruz Rodrigues, Andréia, Bilha, Juliana Kafka, Pereira, Priscila Romero Mazzini, de Souza, Clóvis Wesley Oliveira, Passarini, Michel Rodrigo Zambrano, Uliana, Marciana Pierina
• Format: Article
• Language: English
• Subjects: Bacteria - drug effects; Bacteria - radiation effects; Biomedical and Life Sciences; Biotechnology and Industrial Microbiology - Research Paper; Candida albicans - drug effects; Candida albicans - radiation effects; Food Microbiology; Life Sciences; Light; Medical Microbiology; Microbial Ecology; Microbial Genetics and Genomics; Microbial Viability - drug effects; Microbial Viability - radiation effects; Microbiology; Micrococcus luteus - drug effects; Micrococcus luteus - radiation effects; Mycology; Photochemotherapy - methods; Photosensitizing Agents - chemistry; Photosensitizing Agents - pharmacology; Porphyrins - chemistry; Porphyrins - pharmacology; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - radiation effects; Staphylococcus aureus - drug effects; Staphylococcus aureus - radiation effects
• ISSN: 1517-8382; 1678-4405; 1678-4405
• DOI: 10.1007/s42770-024-01278-1

In recent years, some microorganisms have shown resistance to conventional treatments. Considering this increase in resistant pathogens, treatment alternatives are needed to promote greater treatment efficiency. In this sense, antimicrobial photodynamic therapy (aPDT) has been an alternative treatment. This technique uses a photosensitizer that is activated by light with a specific wavelength producing reactive species, leading to the death of pathogenic microorganisms. In this study, bacteriochlorophyll derivatives such as bacteriochlorin metoxi (Bchl-M) and bacteriochlorin trizma (Bchl-T) obtained from purple bacterium ( Rhodopseudomonas faecalis ), were evaluated as photosensitizers in the aPDT. Photodynamic inactivation (PDI) of the microorganisms Staphylococcus aureus , Micrococcus luteus, Candida albicans and Pseudomonas aeruginosa was investigated with both bacteriochlorins (Bchl-M and Bchl-T) at different concentrations (1, 15 and 30 µM for S. aureus; 1, 15, 30, 45, 60 and 75 µM for M. luteus ; 30, 60, 90, 105, 120 and 150 µM for C. albicans; and 200 µM for P. aeruginosa ) and different doses of light (20 and 30 J/cm 2 for S. aureus and M. luteus; 30 and 45 J/cm 2 for C. albicans; and 45 J/cm 2 for P. aeruginosa) to inactivate them. Both photosensitizers showed good activation against S. aureus and for M. luteus, we observed the inactivation of these microorganisms at approximately 3 log, showing to be a good photosensitizers for these microorganisms.