Investigation and Application of Bacillus licheniformis Volatile Compounds for the Biological Control of Toxigenic Aspergillus and Penicillium spp

The present study was designed to investigate the antagonistic activity of Bacillus licheniformis BL350-2 against mycotoxigenic strains of Aspergillus and Penicillium. In vitro coincubation for 5 days indicated Aspergillus westerdijkiae BA1 as the most sensitive strain, with a growth inhibition of 62%, followed by A. carbonarius MG7 (60%), Penicillium verrucosum MC12 (53%), A. niger MC05 (50%), A. flavus CM5 (49%), A. parasiticus SB01 (47%), and A. ochraceus MD1 (44%). Likewise, the majority of the tested strains on exposure to bacterial volatiles showed complete inhibition of mycotoxin synthesis. In vivo assays on maize ears resulted in 88% reduction in A. flavus CM5 growth and complete inhibition of fungal sporulation and aflatoxin accumulation. The GC-MS-based volatile profile showed 3-methyl-1-butanol as the most abundant compound. The findings of the present study advocate that B. licheniformis BL350-2 is suitable as a biocontrol agent against mycotoxigenic fungi, at least during storage of cereal grains.