Aflatoxin M1-Binding Ability of Selected Lactic Acid Bacteria Strains and Saccharomyces boulardii in the Experimentally Contaminated Milk Treated with Some Biophysical Factors

Abstract

There is a growing concern regarding the recurrent observation of aflatoxins (AFs) in the milk of lactating animals. Regarding this, the present study was conducted to assess the aflatoxin M1 (AFM1)-binding ability of three species, namely Lactobacillus rhamnosus, L. plantarum, and Saccharomyces boulardii, inAFM1-contaminatedmilk. The mentioned species were administeredatthe concentrations of107 and 109 CFU/mLto skimmed milk contaminated with 0.5 and 0.75 ng/mL AFM1 within the incubation times of 30 and 90 min at 4°C and 37°C. Lactobacillus rhamnosus was found to have the best binding ability at the concentrations of 107 and 109 (CFU/ml), rendering 82% and 90% removal in the milk samples with 0.5 and 0.75 ng/ml AFM1, respectively. Accordingly, this value at 107 and 109 CFU/ml of L. plantarum was obtained 89% and 82% with 0.75 ng/ml of AFM1, respectively. For S. boulardii at 107 and 109 CFU/ml, the rates were respectively estimated at 75% and 90% with 0.75 ng/ml of AFM1. The best AFM1-binding levels for L. rhamnosus, L. plantarum, and S. boulardii were 91.82±10.9%, 89.33±0.58%, and 93.20±10.9, respectively, at the concentrations of 1×109, 1×107, and 1×107 CFU/ml at 37, 4, and 37°C, respectively. In this study, the maximum AFM1 binding (100.0±0.58) occurred while a combination of the aforementioned probiotics was employed at a concentration of 1×107 CFU/ml at 37°C with 0.5 ng/ml AFM1, followed by the combination of L. rhamnosus and L. plantarum (95.86±10.9) at a concentration of 1×109 CFU/ml at the same temperature with 0.75 ng/ml AFM1. It was concluded that the use of S. boulardii in combination with Lactobacillus rhamnosus and L. plantarum, which bind AFM1 in milk, can decrease the risk of AFM1 in dairy products.

Keywords: AFM1; Lactobacillus plantarum; Lactobacillus rhamnosus; Milk; Saccharomyces boulardii; decontamination.

Figure 1

A schematic representation of in vitro experimentation on the exposure of some probiotics to AFM1-contaminated skim milk at different concentrations, temperatures, and incubation times.