Decontamination of aflatoxin M1 in yogurt using Lactobacillus rhamnosus LC‐4

This study aimed to evaluate the ability of the Lactobacillus rhamnosus strain LC‐4 to bind aflatoxin M1 (AFM1) in phosphate‐buffered saline (PBS) and yogurt. Bacterial cells were subjected to heat, acid, and alkali treatments. The AFM1‐binding rate of acid‐treated bacteria was of 78.63 ± 0.52%. The binding of L. rhamnosus LC‐4 to AFM1 was partially reversible and the binding of AFM1 was more stable when treated bacteria were used. The involved components of the cell wall in AFM1 binding were determined, with peptidoglycan playing a critical role. The integrity of the bacteria was also highly important for detoxification ability, and this ability was influenced by different factors such as temperature, pH, and toxin concentration, and so on. L. rhamnosus LC‐4 retained its detoxification ability in yogurt. The pH and bacterial concentration slightly affected the binding of AFM1 to L. rhamnosus LC‐4 during storage time. These results indicate that L. rhamnosus LC‐4 may be applied to reduce the concentration of AFM1 in yogurt. PRACTICAL APPLICATIONS: In the present work, we determined the involved components of the cell wall in AFM1 binding and different factors influencing the binding process. The integrity of the cell wall is indispensable for AFM1 binding and peptidoglycans were critical components. Understanding the mechanism of AFM1 binding by probiotic bacteria is contributed to further optimizing decontamination processes. Our study provides potential future applications to reduce AFM1 bioavailability by L. rhamnosus LC‐4 in yogurt.