Aflatoxin is a natural toxin produced by some fungi that commonly contaminate agricultural products such as corn and peanut. There are few approaches to control aflatoxin occurrence in pre or post-harvest stages, either by physical, chemical, and microbiological methods. Some lactic acid bacteria, including Lactobacillus acidophilus have been reported to bind aflatoxin B1 (AFB1) in an aqueous medium. This research aimed to evaluate the effects of AFB1 concentration, temperature, and pH on the ability of L. acidophilus SNP-2 to bind AFB1. Initial AFB1 concentration were 20 ppb, 40 ppb, 60 ppb, and 80 ppb. AFB1 binding by L. acidophilus SNP-2 was carried out in phosphate saline buffer with pH ranged from 4.0 to 7.3; and temperature 40C, 280C, and 370C for incubation time of 24 hr. The amounts of initial and unbound AFB1 were determined by using High Performance Liquid Chromatography (HPLC). The results indicated that increasing initial AFB1 concentration in the medium did not significantly affect the percentage of AFB1 binding, but affected the AFB1 binding velocity. The highest AFB1 binding on the cell was obtained at temperature of 370C. Binding of AFB1 by L. acidophilus SNP-2 in phosphate saline buffer pH 5.0 at 370C was rapid, and about 50% AFB1 was bound throughout a 24-h incubation period.
Keywords: Aflatoxin, Lactobacillus acidophilus, concentration, pH, temperature