N-METHYLENEPHOSPHONIC CHITOSAN (NMPC) EXERTS CITOTOXICITY IN FUNGAL CELLS

MESAS, FLORENCIA; ALBERTENGO, LILIANA; ZUÑIGA, ADRIANA; DEBBAUT, ADRIANA; RODRIGUEZ, MARIA SUSANA; CASALONGUE, CLAUDIA; TERRILE, MARIA CECILIA; SILVEYRA, MARIA XIMENA; MENDIETA, JULIETA RENEE

Buenos Aires

Congreso; Reunion Conjunta de Sociedades de Biociencias; 2017

The aqueous solubility of chitosan depends on the degree of protonationof the NH2 group by acid treatment, which limits its versatilityin biological fluids. However, N-methylenephosphonic chitosan(NMPC) is a chitosan derivative which hydrosolubility is improveddue to the addition of aminoalkylphosphonic ligands. The aim ofthis study was to study whether NMPC has antifungal properties onphytopathogenic fungus Fusarium solani f sp. eumartii (F. solani).Firstly, we analyzed the effect of NMPC on germination of F. solanispores. In vitro quantitative assays showed that NMPC exertedantifungal properties in a dose dependent manner, displaying anestimated IC50 value=2.5 µg/ml. To investigate whether NMPC hasa lethal effect on fungal spores, different experimental approacheswere performed. F. solani spores were incubated in the presenceof different concentrations of NMPC for 24 h. Fungal viability wascalculated counting the number of colony forming units (CFU). Inaddition, the effect of NMPC on cell plasma membrane validatedcitoxicity based on the uptake of the fluorogenic dye SYTOX Green.ROS production was in vivo measured by DAB staining in fungalspores upon 4 h post incubation with 2.5 µg/ml NMPC. Beside, tomatocell cultures were incubated with 2.5 and 5 µg/ml NMPC, andcell viability was tested with Evans blue dye. The results showedthat at fungicide doses, NMPC did not produce tomato cell death.Simultaneous analysis of cell viability, cell permeabilization and activationof ROS generation explained integrative citotoxic propertiesmediated by NMPC on fungal cells.