Abstract
Lactobacillus acidophilus isolated from newly born infant's stool, purified and identified by studding the morphological and biochemical tests then compared with Bergey's manual for the Holt et al (1994). Also studied the impact of the inhibitory to the extracted filtrate of the bacteria Lactobacillus acidophilus on some types of pathogenic bacteria, as found the inhibition area (inhibition zone) to the Staphylococcus aureus 14 mm and were the species most resistant is Escherichia coli and Salmonella typhi amounting to 12 mm. Also studied the effect of bacteria Lactobacillus acidophilus on the growth of fungus Aspergillus parasiticus and production of aflatoxins B1, B2 and G1, G2 in the media component MRS and extract corn as the results show for high acidity and low pH due to the growth ofLactobacillus acidophilus which produced antibacterial activity (bacteriocine) and led to a reduction in mold growth and toxin production to 6 days of incubation and then increased in the mold growth and acidity decreased with increase in pH and the amount production of aflatoxin poison B1, G1.