Antifungals from Zuccagnia punctata cav.: isolation, identification and usefulness for control of toxigenic ear rot pathogens

JIMENEZ, C.M.; SAMPIETRO, D.A.; SGARIGLIA, M.A.; SOBERÏ¿½N, J.R.; VATTUONE, M.A.

NATURAL PRODUCT COMMUNICATIONS

NATURAL PRODUCTS INC

Lugar: Westerville, Ohio; Año: 2014 vol. 9 p. 1461 - 1464

1934-578X

Infusion, tincture and decoction from leaves of Zuccagnia punctata Cav. were assayed on Fusarium verticillioides, Fusarium graminearum sensu stricto, Fusarium boothii, Fusarium meridionale, Fusarium subglutinans and Fusarium thapsinum growth. The tincture showed the lowest IC50 on mycelial growth. A diethyl ether fraction of the tincture showed the highest antifungal activity on F. verticillioides and F. graminearum in microdilution assays. The antifungal constituents were separated by silica gel chromatography and identified as 2´,4´-dihydroxychalcone, 2´,4´-dihydroxy-3´-methoxychalcone and 7-hydroxy-3´,4´-dimethoxyflavone. Chalcones had the lowest MIC and MFC values on F. verticillioides and F. graminearum sensu stricto. The 2´,4´-dihydroxychalcone was mildly toxic and the remaining identified compounds were non-toxic in the brine shrimp assay. 2´,4´-dihydroxychalcone in mixtures with commercial food preservatives showed additive effects on F. graminearum sensu stricto and synergistic ones on F. verticillioides. The 2´,4´-dihydroxy-3´-methoxychalcone showed synergistic effects in mixtures. Our results suggest that addition of chalcones to food preservatives allows to reduce the doses of the laters required for control of Fusarium species.