title: Furocoumarins and coumarins photoinactivate Colletotrichum acutatum and Aspergillus nidulans fungi under solar radiation.
abstract: The increasing tolerance to currently-used fungicides is a major problem both in clinical and agricultural areas leading to an urgent need for the development of novel antifungal strategies. This study investigated the in vitro antimicrobial photo treatment (APT) of conidia of the plant-pathogenic fungus Colletotrichum acutatum and the ascomycete Aspergillus nidulans with the furocoumarins 8-methoxypsoralen (8-MOP) and isopimpinellin, and a mixture of two coumarins (7-methoxy coumarin and citropten). Subcellular localization of the photosensitizer 8-MOP was also determined in C. acutatum conidia. Additionally, the effects of APT on the leaves of the plant host Citrus sinensis were determined. APT with 8-MOP (50μM) led to a reduction of approximately 4 logs in the survival of the conidia of both species, and the mixture of the two coumarins (12.5mgL(-1)) resulted in a reduction of approximately 4 logs for A. nidulans and 3 logs for C. acutatum. Isopimpinellin (50μM) displayed a reduction of 4 logs for A. nidulans but less than 2 logs for C. acutatum. Washing the conidia to remove unbound photosensitizers before light exposure reduced the photodynamic inactivation of C. acutatum both with 8-MOP and the mixture of the two coumarins. The reduction was smaller for A. nidulans. 8-MOP spread throughout the cytoplasm and accumulated in structures such as lipid bodies of C. acutatum conidia. No damage to orange tree leaves was observed after APT with any of the photosensitizers.
authors: Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors: Henrique D
authors: HD
authors: de Menezes
authors: Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors: Ana C
authors: AC
authors: Pereira
authors: Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors: Guilherme T P
authors: GT
authors: Brancini
authors: Citrosuco S/A Agroindústria, Matão, Brazil.
authors: Helton Carlos
authors: HC
authors: de Leão
authors: Departamento de Fitopatologia e Nematologia, Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, Piracicaba, Brazil.
authors: Nelson S
authors: NS
authors: Massola Júnior
authors: Departamento de Física, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors: Luciano
authors: L
authors: Bachmann
authors: School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool L3 3AF, United Kingdom.
authors: Mark
authors: M
authors: Wainwright
authors: Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
authors: Jairo Kenupp
authors: JK
authors: Bastos
authors: Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil; Research Support Center in Natural and Synthetic Products, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil. Electronic address: gbraga@fcfrp.usp.br.
authors: Gilberto U L
authors: GU
authors: Braga
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D001233:Aspergillus nidulans / Q000187:drug effects*; D002957:Citrus / Q000737:chemistry / Q000382:microbiology; D020231:Colletotrichum / Q000187:drug effects* / Q000472:pathogenicity; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011564:Furocoumarins / Q000302:isolation & purification / Q000494:pharmacology*; D008730:Methoxsalen / Q000302:isolation & purification / Q000494:pharmacology*; D015394:Molecular Structure; D017319:Photosensitizing Agents / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000382:microbiology; D013172:Spores, Fungal / Q000187:drug effects; D013472:Sunlight
chemical_list: D000935:Antifungal Agents; D003374:Coumarins; D011564:Furocoumarins; D017319:Photosensitizing Agents; C015304:isopimpinellin; C037446:5,7-dimethoxycoumarin; D008730:Methoxsalen
keywords: Antimicrobial photo inactivation; Aspergillus nidulans; Colletotrichum acutatum; Coumarins; Furocoumarins; Photoantimicrobial