Isolation and characterization of antifungal metabolites of Bacillus subtilis strains BZR 336g and BZR 517 using the modified bioauthography method

The ability of B. subtilis to produce a large number of biologically active metabolites of diverse structure and properties can largely determine its fungicidal effect against particularly dangerous pathogenic fungi. In this regard, we have studied the fungicidal activity and properties of the antifungal metabolites of active strains B. subtilis BZR 336g and BZR 517. The approach we used, inсluding purification by extraction with ethyl acetate, thin-layer chromatography (TLC), UV fluorescence, tests with detection reagents, spectroscopy and bioautography, showed the potential of the studied B. subtilis strains to accumulate the complex of active metabolites exhibiting antifungal effect from fungistatic to fungicidal. Bioautographic method was modified by use of the causative agents of harmful diseases, F. oxysporum var. orthoceras and Alternaria sp. as test organisms, which allowed us to assess in vitro the antifungal activity. Patterns of the antifungal compounds differed between the strains in TLC mobility and UV fluorescence...