Control of Aspergillus flavus growth and aflatoxin B1 production using photodegraded eugenol under different conditions of water activity

NESCI, A.; GAMBETTA, C.; MASSAD, W.; GARCÍA, N.; ETCHEVERRY, M.

Edinburgo

Conferencia; IMC9: The Biology of Fungi.; 2010

International Mycological Association

The effects of eugenol and photodegraded eugenol, by direct and sensibilised photolysis, at concentrations of 100, 200 and 300 ppm on growth and aflatoxin B1 production by Aspergillus flavus Link were evaluated. Studies on growth rate and aflatoxin B1 production were carried out in meal extract agar in vitro in relation to a water activity aw of 0.99, 0.97 and 0.95. Eugenol at three time of photolysis at concentrations of 100, 200 and 300 ppm was effective increasing lag phase and inhibiting growth rate of the strain assayed. A. flavus were much more sensitive at all photodegraded eugenol concentrations tested, on growth rate at aw = 0.95. Photodegraded eugenol at 300 ppm completely inhibited aflatoxin B1 production by A. flavus at aw = 0.97 and 0.95. Decreased aflatoxin B1 levels in comparison with the control were observed with 300 ppm at aw = 0.99. The data show that eugenol can be considered as effective fungitoxicant for A. flavus in in vitro assay. The information obtained is part of an ongoing study to develop an integrate management of Aspergillus section Flavi and pest vectors and to diminish the risk of aflatoxin contamination at the storage level.