Screening of microorganisms strains from native dairy products of the north west of Iran in the detoxification aflatoxin B1 in stimulated gastrointestinal conditions

Abstract

The contamination of foods and feeds with mycotoxins is a significant problem, and acute exposure to a high level of aflatoxins leads to aflatoxicosis, which cause rapid death due to liver failure. It is anticipated that consumption of probiotic microorganisms with capability of binding to aflatoxins, can reduce the risk of Aflatoxin B1 (AFB1) on human health up to a certain level. Therefore, the present study was conducted to assess the ability of probiotic bacteria and yeasts strains isolated from traditional dairy products in the northwest of Iran to reduce AFB1 in gastrointestinal simulated conditions. In this study, the bacteria and yeasts count and AFB1 concentration were adjusted to 1 × 1010 cfu/ml, 2 × 108 cfu/ml and 10 ppb, respectively. Then, the samples were incubated in the simulated medium, human gastric secretions and small intestine. The concentration of residual AFB1 was determined using ELISA. The results were statistically analyzed by SPSS 20 software. The standard curve for AFB1 at concentration range of 0 - 50 ng / ml was drawn by Excel software. Presence of native isolated bacteria and yeasts in the simulated gastrointestinal tract condition showed a significant effect on AFB1 reduction (P<0.05). The ability of native probiotic microorganisms for reduction AFB1 was strain dependent. All strains showed the ability to reduce aflatoxin, with the highest Percentage reduction for the bacterial strains, ranging between 8.38% to 31.14% and 1.96% to 30.46% for yeast. The highest binding ability amang bacteria was belonged to Lactobacillus rhamnosus (31.14%) and amang yeasts belonged to Saccharomyces cerevisiae (30.46%). The probiotic bacteria and yeasts strains isolated from traditional dairy products was a good biological agent for elimination or reduction of AFB1 in the human gastrointestinal tract. They could help to reduce the harmful effects of AFB1 through consumption of contaminated food and or thereby enhance food safety.