Cooperative and competitive antimicrobial photodynamic effects induced by a combination of methylene blue and curcumin

Autor(es)

Dias, Lucas D. ^[1] ; Correa, Thaila Q. ^[1] ; Bagnato, Vanderlei S. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13566590 Sao Carlos - Brazil

^[2] Texas A&M Univ, Dept Biomed Engn, College Stn, TX 77843 - USA

• Tipo de documento: Artigo Científico
• Fonte: LASER PHYSICS LETTERS; v. 18, n. 7 JUL 2021.
• Citações Web of Science: 0

Resumo

Alternatives techniques to combat bacteria and their resistance mechanisms are urgently needed in health and industrial sectors such as hospital environments and the food industry. Antimicrobial photodynamic therapy produces oxidative stress via multiple cell death mechanisms which are less prone to the development of resistance mechanisms by bacteria. We evaluate the simultaneous use of two photosensitizers (a nitrogen based-photosensitizer namely methylene blue and curcumin) at the same photodynamic protocol against Staphylococcus aureus bacteria and show their competitive and cooperative effects. We demonstrate that the use of two photosensitizers concomitantly used on bacterial reduction may produce effects that depend on: (a) attenuation of light by photosensitizers molecules; (b) shielding effect and steric hindrance by photosensitizers; (c) inter- and intra-photobleaching. Furthermore, we observe that the combined use of methylene blue and curcumin, both being photoactivated simultaneously (at 450 nm and 660 nm) is not an additive process. This study paves the ways and also shows the challenges for simultaneous use of two photosensitizers in an antimicrobial photodynamic protocol. (AU)

• Processo FAPESP: 14/50857-8 - INCT 2014 - de Óptica Básica e Aplicada às Ciências da Vida
• Beneficiário: Vanderlei Salvador Bagnato
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/07276-1 - CEPOF - Centro de Pesquisa em Óptica e Fotônica
• Beneficiário: Vanderlei Salvador Bagnato
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 19/13569-8 - Estudo dos Mecanismos de Ação em Terapia Fotodinâmica: Do Fotossensibilizador à Aplicação Prática
• Beneficiário: Lucas Danilo Dias
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado