Investigating the Impact of Flavonoids on Aspergillus flavus : Insights into Cell Wall Damage and Biofilms

• Published in: Journal of fungi (Basel) Vol. 10; no. 9; p. 665
• Main Authors: Castano-Duque, Lina, Lebar, Matthew D, Mack, Brian M, Lohmar, Jessica M, Carter-Wientjes, Carol
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 23.09.2024; MDPI
• Subjects: aflatoxin; Aflatoxins; Antifungal agents; Antioxidants; apigenin; Aspergillus; Aspergillus flavus; Bacteria; Biofilms; Biosynthesis; Carcinogens; cell wall; Cell walls; Climate change; Cocoa; Flavonoids; Food contamination & poisoning; Fungal infections; Genes; Investigations; Isoflavones; luteolin; Metabolites; Osmotic stress; Pathogens; Physiological aspects; Plant breeding; Plant protection; Plants; Public health; Quercetin; RNA sequencing; Sequence analysis; Sorghum; Toxicity; United States > US; apigenin; Aspergillus; luteolin; quercetin; aflatoxin; cell wall
• ISSN: 2309-608X; 2309-608X
• DOI: 10.3390/jof10090665

, a fungus known for producing aflatoxins, poses significant threats to agriculture and global health. Flavonoids, plant-derived compounds, inhibit proliferation and mitigate aflatoxin production, although the precise molecular and physical mechanisms underlying these effects remain poorly understood. In this study, we investigated three flavonoids-apigenin, luteolin, and quercetin-applied to NRRL 3357. We determined the following: (1) glycosylated luteolin led to a 10% reduction in maximum fungal growth capacity; (2) quercetin affected cell wall integrity by triggering extreme mycelial collapse, while apigenin and luteolin caused peeling of the outer layer of cell wall; (3) luteolin exhibited the highest antioxidant capacity in the environment compared to apigenin and quercetin; (4) osmotic stress assays did not reveal morphological defects; (5) flavonoids promoted cell adherence, a precursor for biofilm formation; and (6) RNA sequencing analysis revealed that flavonoids impact expression of putative cell wall and plasma membrane biosynthesis genes. Our findings suggest that the differential effects of quercetin, luteolin, and apigenin on membrane integrity and biofilm formation may be driven by their interactions with fungal cell walls. These insights may inform the development of novel antifungal additives or plant breeding strategies focusing on plant-derived compounds in crop protection.