Posted by The genus Fusarium comprises filamentous fungi widely distributed in soil and plants, representing threats to various organisms, including plants, animals, and humans. Conventional fungicides have limitations, leading to a growing interest in sustainable control methods such as photodynamic inactivation (PDI) of microorganisms. This study evaluates the antifungal photodynamic activity of meso-substituted porphyrin derivatives (H2Pors 1a–3a), which each structure is composed by three thiopyridinium groups and one cyclodextrin group (α-, β-, or γ-CD). These water-soluble porphyrin-cyclodextrin derivatives were prepared and tested on Fusarium oxysporium conidia. Photoinactivation tests were conducted at different concentrations (1.0, 2.5, and 5.0 μM) under white light exposure at an irradiance of 25 mW.cm−2 for 60 min (light dose of 90 J.cm−2). Fungal inactivation was observed for all molecules at the highest tested concentration. H2Por 3a demonstrated the strongest PDI effect, achieving complete inactivation of the conidia (5.0 log10 viability reduction) at 2.5 and 5.0 μM and partially at 1.0 μM (∼3.0 log10 viability reduction).
Claudia P.S. Ribeiro, Isabel N. Sierra-Garcia, Ângela Cunha, Leandro M.O. Lourenço (2026) In vitro eradication of Fusarium oxysporium conidia using light-triggered thiopyridinium porphyrin-cyclodextrin dyes. Journal of Photochemistry and Photobiology A: Chemistry 471, 116719.
https://doi.org/10.1016/j.jphotochem.2025.116719.
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