Evaluation of kinetic model of aflatoxin B1 adsorption by Saccharomyces cerevisiae treated with acid and ultrasonic in Sangak bread dough

Because food contamination with mycotoxins is a serious problem, in this study, the ability of aflatoxin B1 to bind to the Saccharomyces cerevisiae cell wall was investigated to reduce Sangak bread dough toxicity. For this purpose, aflatoxin B1 at a concentration of 10 μg/kg inoculated to the dough containing 0.27 g of viable saccharomyces cerevisiae, acid treated saccharomyces cerevisiae, and ultrasonicated saccharomyces cerevisiae. Toxin adsorption kinetics were investigated at 24, 28 and 32 °C and 8, 16 and 24 h incubation. The trend for toxin adsorption was as follows: ultrasonicated yeast ˃ acidic yeast ˃ viable yeast. With increasing the incubation temperature and time, toxin adsorption increased in acid treated and ultrasonicated Saccharomyces cerevisiae, while active yeast samples showed the highest toxin removal at 28 °C. The results showed that the adsorption kinetics by active yeast and acid treated yeast could be explained by means of pseudo first order model, while for the ultrasonicated yeast, the data are more consistent with the pseudo second order model. Also, both surface adsorption and intra-particle diffusion contributed to the adsorption rate steps. Therefore, live or non-living yeast cells are suitable biological agents for aflatoxin removal in a contaminated culture medium, however, ultrasonic treatment is more effective.