Impact of sub-lethal 2(3)-tert-butyl-4 hydroxyanisole (BHA) microcapsules on behavior of Aspergillus flavus in culture medium and peanut seeds

Abstract

The aim of this work was the evaluation of physiological behavior of Aspergillus flavavus affected by the application of sub-lethal doses of microencapsulated 2(3)-tert-butyl-4 hydroxyanisole (BHA). For this , peanut meal extract agar (PMEA) and peanut kernels with modified water activity (aw) (0.96 and 0.99) and a sub-lethal dose (0.6 mM) of an BHA formulation was used. Fungl physiological aspects as growth rate, tme to growt and AFB1 evolution were modified by the formulation, especially on PMEA at both aw. In general, conidial and vesicle size of the mold only were affected by growth substrate, being higher on sterile seed than on PMEA regardless of aw condition . However, positive correlation (p<0.05) observed in control betweenradius and biomass responses was altedred by the application of the formulation, mainly under the lowest aw in both substrate evaluated. Finally, presence of encapsulated antioxidant showed significant change in Pearson coefficients respect to the controls for all studiend parameters.As conclusin, sub-lethaldoses formulation lead in reduction on growt and toxin accumulation, but conidial and vesicle size were not affected. Results of this work indicate the need to consider both fungal primary and secondary metabolism to determine the effect of food grade antioxidants formulation.