Binding efficiency of lactic acid bacteria strain Lactobacillus sp. to the reduction of aflatoxin B1 in aflatoxin B1-contaminated peanuts

Abstract

Exposure of aflatoxin B1 (AFB₁) contaminated in foods has been known as a cause of hepatocellular carcinoma. Therefore, this study aimed to investigate the decontamination processes of AFB₁ by using lactic acid bacteria (LAB); Lactobacillus pentosus, L. plantarum and L. casei subsp. rhamnosus to reduce AFB₁ in AFB₁-contaminated peanuts. AFB₁ was extracted and analyzed by high performance liquid chromatography equipped with florescence detector (HPLC-FLD). Results showed ability of LAB to bind AFB₁ (50 ng/ml) through experimental period (0-120 hours) were found. At 24 hours, the maximal binding time, %binding of aflatoxin fraction (%BAF) for L. pentosus, L. plantarum and L. casei subsp. rhamnosus were 55.77%, 51.26% and 47.98%, respectively. However, %BAF for the binding to AFB₁ in AFB₁-contaminated peanuts were 27.48%, 23.93% and 23.58%, respectively when compared to tested samples without LAB, indicating capability of LAB to reduce AFB₁ from peanuts. Further study was performed by using in vivo digestion model to verify the bacterial binding capability in the digestive system. Tested bacterial strains exhibited %BAF at 55.54%, 38.78% and 12.10%, respectively. The increase and decrease of %BAF when compared with the condition devoid of digestive fluids could be accounted from the amount of AFB₁ released from peanuts or condition that affected bacterial stability. Results showed that Lactobacillus sp. were capable of binding AFB₁ in peanuts in the humanmimic digestive system which might imply possibility for the use of LAB to reduce AFB₁ contamination in foods and could be expanded for product development in the future.