Application of Bacillus Safensis Lau 13 Metabolite for the Control of Growth and Aflatoxin Production by Aspergillus Flavus on Stored Maize Grains

Abstract

The uncontrolled rise in the use of synthetic chemicals for post-harvest preservation of farm produce has resulted in ecological deterioration and contamination of crop products with harmful chemical residues. Thus, the use of bioactive materials as a substitute for common synthetic chemicals in controlling postharvest microbial contamination of crops has gained tremendous attention due to their eco-friendliness, cost-effectiveness, and sustainability. This study aims to evaluate the antifungal effect of Bacillus safensis LAU13 metabolites (METOX) for the control of Aspergillus species growth and aflatoxin production on stored maize grains. The METOX was produced by Bacillus safensis LAU 13 during a three-day submerged fermentation cultivation. Characterisation of METOX by gas chromatography-mass spectrometry (GC-MS) revealed the presence of bioactive compounds, predominantly aldehyde derivatives, 4-Dodecen-1-al (13.5%) and Octanal,3,7-dimethyl (13%). The METOX exhibited a potent inhibitory effect against the aflatoxin-producing strains of A. flavus and A. niger isolated from stored maize grains, as it induced 62% and 16% fungal growth inhibition against the isolated strains of A. flavus and A. niger, respectively. Hence, the results obtained herein suggest that the METOX produced by B. safensis LAU 13 has promising applications as a bioactive material for the sustainable control of aflatoxin-producing fungal species in stored grains.