Investigation the antifungal activitiy of Lactobacillus against Aspergillus niger and Penicillium oxalicum

This study investigated the antifungal activity against Aspergillus niger CBS 76997 and Penicillium oxalicum 20B of several Lactobacillus strains (LAB). The in vitro antifungal activity of cell-free supernatants and biomass of Lactobacillus strains against the growth of A. niger CBS 76997 and P. oxalicum 20B was determined by monitoring the fungal colony diameter over time by spot inoculation method and double layer method. The antifungal effect was dependent on LAB and fungi strains. The control sample of A. niger and P. oxalicum reached the mycelial growth diameter 100% (85 mm) after 5 days and 10 days, respectively. The cell-free supernatant and biomass of LAB could inhibit the growth of tested fungi ranging from 35.3% to 84.7% and from 30.6% to 100%, respectively. When inoculated, LAB can delay the spore-forming process from 2 to 10 days. The research results demonstrated the potential application of lactic acid bacteria as a biological inhibitor of fungal growth in the preservation and processing of food products.