| Nowadays, natural antimicrobial agents using as alternatives for the previous chemical preservatives and reducing the amount of chemical preservatives in food has becoming hot spots of food science researches. It indicated that some lactic acid bacterium have the positive functions to inhibit the growth of the mold and the formation of the toxin in recent reports.756 strains of lactic acid bacteria isolated from many sorts of pickles, bean dregs, chicken and pig intestines were screened for antifungal activity by the agar-well diffusion assay. Among of the 756 strains isolated, 6 strains showed strong inhibitory activity against A.flavus. These isolates were identified by physiological and biochemical characteristics and 16S rRNA gene sequencing. The results showed that 3 strains were Lactobacillus plantarum, 2 strains were L. alimentarius and 1 strain was L. arizonenensis.The 6 strains have the broad-spectrum inhibition of fungi, and all of them have a certain function of inhibitory against Aspergillus niger, Penicillium sp., Rhizopus sp. and Fusarium sp. Among them, the strain of E3 has the positive inhibitory effects against all these four indicator bacterium. Despite of E3, the other five strains have no obvious effects on the Gibberella sp. and Sphaerosporula sp.The antibacterial substances produced by the six lactic acid bacteria were definitely not bacteriocin by saturation ammonium sulfate precipitation and acetone precipitation tested. After the detail measurement, such as their fermentation supernatant of the total acid, the related effects on the growth of A. flavus, the related effects on the antimicrobial activity of lactic acid bacteria and supernatant concentration on the antibacterial effect of Aspergillus flavus, their original pH were about 4, we can conclude that the antibacterial component is a metabolite of lactic acid bacteria. It can inhibit the A. flavus and other fungi, when it is in a low pH value.
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