Biocontrol Activity of New Lactic Acid Bacteria Isolates Against Fusaria and Fusarium Mycotoxins

Abstract

As significant fungal pathogens of crops, Fusaria species contaminate various food and feed commodities. Some of the Fusarium spp. secondary metabolites (e.g., trichothecenes, zearalenone, and fumonisins) are widely known toxic molecules (mycotoxins) with chronic and acute effects on humans and animals. The growing demand for safer, pesticide-free food drives us to increase biological control during crop growing. Recent research suggests that lactic acid bacteria (LABs) as biocontrol are the best choice for extenuating Fusarium mycotoxins. Newly isolated LABs were tested as antifungal agents against Fusarium verticillioides, F. graminearum, and F. oxysporum. The characterized and genetically identified LABs belonged to Limosilactobacillus fermentum (SD4) and Lactiplantibacillus plantarum (FCW4 and CB2) species. All tested LABs and their cell-free culture supernatants showed antagonism on the MRS solid medium. The antifungal activity was also demonstrated on surface-sterilized wheat and peanuts. The germination test of corn kernels proved that the LAB strains SD4 and FCW4 significantly (p < 0.05) enhanced root and shoot development in plantlets while simultaneously suppressing the outgrowth of F. verticillioides. Small-scale corn silage fermentation revealed the significant effects of SD4 supplementation (decreased zearalenone, lower mold count, and total reduction of deoxynivalenol) within the mixed populations.