Rutin hydrate induces autophagic cell death and oxidative stress response in phytopathogenic fungus Fusarium graminearum

Abstract

Fusarium graminearum infects cereal crops of high commercial and nutritional value such as barley, wheat, and maize, and causes various diseases. Due to the increasing world population and changing climatic conditions, the importance of controlling this pathogen is increasing. The aim of this study was to investigate the potential antifungal effect of the flavonoid compound rutin hydrate (RH) on the F. graminearum PH-1 reference strain at different levels. The EC 50 (half effective concentration) value was determined by the agar dilution method on the PDA (potato dextrose agar) medium containing different concentrations of rutin hydrate. To examine the effect of rutin hydrate on cell viability, the WST-1 toxicity test was performed. To determine the effect of rutin hydrate on genomic stability and methylation profiles, the CRED-RA (coupled restriction enzyme digestion-random amplification) analysis was performed. To determine the expression levels of atg5 , cat , kmet1 , sporulation ( mgv1 ), and apoptosis ( mst20 ) related genes, the qRT-PCR (quantitative real-time polymerase chain reaction) was performed. To detect the presence of oxidative stress and autophagy, the DCF-DA (2’,7’-dichlorofluorescein) and MDC (monodansylcadaverine) staining tests were used. The EC 50 value of rutin hydrate was determined as 580 µg mL −1 . The WST-1 analysis revealed that rutin hydrate caused cytotoxicity (58.53%) in F. graminearum ( p < 0.05). In the CRED-RA analysis, genomic template stability (GTS) decreased by 9.53%, and the methylation levels for Hap II and Msp I enzymes were 11.6% and 5.24%, respectively. There was a significant difference in the atg5 (2.66 ± 0.48; p < 0.01), cat (3.00 ± 0.46; p < 0.01), and kmet1 (6.29 ± 2.24; p < 0.05) expression in the rutin hydrate-treated samples. Autophagy and oxidative stress response with a significant difference ( p < 0.05) in the rutin hydrate-treated F. graminearum was confirmed by DCF-DA and MDC tests. This is the first report demonstrating the antifungal effect of rutin hydrate on F. graminearum at physiological, transcript, and epigenetic levels.