Abstract: Lactobacillus acidophilus(L. aci.) is a probiotics strains in the human intestinum, also is a important activitymicroorganisms in the milk products. The main aim of this work was to study ability of binding sterigmatocystin(ST) byLactobacillus acidophilus cells and the mixed proteins from it’s cytoplasm. The results shown that the rate of binding ST for theL. aci. mixed proteins may represent up to 75.8%, but 48.9% of the yeast’s mixed proteins and 32.5% of BSA. After treated withtrypsin or pepsin, the activity of the L. aci. mixed proteins binding ST decreases form 52.2% to 34.3% or 36.1% compared withcontrol test. The rate of binding ST were determined after incubated the mixed proteins with ST for 1,2,3,4 and 5 hours, the rateof L. aci. mixed proteins is higher level (57.2% to 75.7%), but rate of BSA is lower level (14.6% to 34.3%), the rate of yeast’smixed proteins is 70.6% at 1hour down to 19.8% at 5 hours. Treating with heat or HCl may increases the rate of L. aci. bind STfrom 60.5% up to 71.2% or 69.5%. These results apply value reference dates for removing stergmatocystin and processing food.

Key words: sterigmatocystin, Lactobacillus acidophilus, detoxification