Reduction of Aflatoxin B1 in Stored Peanuts (Arachis hypogaea L.) Using Saccharomyces cerevisiae

Abstract

Aflatoxin B1 is a toxigenic and carcinogenic compound produced by Aspergillus flavus and Aspergillus parasiticus. To inhibit aflatoxin contamination of peanuts, seeds of two peanut breeds, IAC Caiapó and IAC Runner 886, were inoculated with A. parasiticus (1.0 × 106 spores per ml) and the yeast Saccharomyces cerevisiae (3.2 ×107 cells per ml) and incubated at 25°C for 7 and 15 days. Two experiments were conducted for each incubation period separately. The treatments were completely randomized, with three replications per treatment. Treatments included the two cultivars and three types of inoculation (pathogen alone, yeast and pathogen, and yeast 3 h before pathogen). Aflatoxin B1 was quantified with a densitometer at 366 nm after thin layer chromatography. Aflatoxin B1 contamination in peanuts was reduced after the addition of S. cerevisiae. The concentration of aflatoxin B1 decreased by 74.4 and 55.9% after 7 and 15 days, respectively. The greatest aflatoxin reduction was observed when S. cerevisiae was inoculated 3 h before the pathogen in IAC Caiapó seeds and incubated for 7 days at 25°C. The use of S. cerevisiae is a promising strategy for biological control of aflatoxin contamination in peanuts.