Antifungal activity of newly isolates of lactic acid bacteria

Abstract

A total of 54 strains of lactic acid bacteria isolated from silage, camel milk and carrot were screened for antifungal activity with overlay and confrontation assay. Six of them, belonging to the genera Lactobacillus, Lactobacillus plantarum and farciminis strains produce antifungal compounds active against Aspergillus spp., Fusarium roseum, Trichoderma spp., Penicillium spp. and Stemphylium spp. Approximately 16.66% of the isolates showed inhibitory activity against Aspergillus spp. The antifungal compounds were originated from organic acids, the maximum antifungal activity was observed at pH 2.0, but it decreased at pH 3.0÷7.0. Inhibitory activity did not change after treatment with proteolytic enzymes, heating, refrigeration and freezing. No inhibitory activity could be detected against the mould Aspergillus spp. with non-concentrated cell free supernatant and volatile substance.