Abstract
Aflatoxin M(1) (AFM(1) ) is a potent mycotoxin which causes serious health concerns in developing countries, where it is mainly found in milk, meat, and other foods. Biological detoxification is a promising method for eliminating AFM(1) . The aim of this work was to search for AFM(1) -degrading bacterial strains from animal waste, soil, and activated sludge. High-performance liquid chromatography and Fourier-transform infrared spectroscopy were used to analyze the AFM(1) degradation products. A strain designated E-1-1-1 was obtained from African elephants feces, with the degradation ratio of AFM(1) reaching 89.55% in 12 hr. Based on morphology, physiological and biochemical tests, and 16S rRNA gene sequence analysis, strain E-1-1-1 was identified as Bacillus pumilus. The culture supernatant of B. pumilus E-1-1-1 degraded AFM(1) effectively, whereas the cells and cell extracts of B. pumilus E-1-1-1 were far less effective. Carbon and nitrogen sources had highly significant effects on the degradation of AFM(1) by B. pumilus E-1-1-1. The AFM(1) -degrading strain, B. pumilus E1-1-1, could have great potential in industrial applications.