Antifungal effect of soil bacteria on pathogenic species of the fungal genera and .

BACKGROUND AND OBJECTIVES

The increasing prevalence of fungal infections due to antifungal resistance underscores the need for novel treatment strategies. The present study aimed to investigate the inhibitory effects of soil-originated antagonistic bacteria against and species.

MATERIALS AND METHODS

Fifty soil samples collected from Isfahan and Khuzestan provinces by using the Zig-Zag method were cultured on glucose-yeast extract (GY) agar around fungal colonies to isolate antagonistic bacteria. Antifungal activity was assessed by measuring clear zones around the colonies of and by co-culture linear method. Potent antagonistic bacteria were identified by 16S rRNA sequencing, and evaluated for antifungal activity using disk diffusion assays compared with amphotericin B and ketoconazole.

RESULTS

Among 50 samples, fifteen showed antifungal effects, yielding 55 bacterial strains. Four isolates with strong antifungal activity against all tested fungi were identified as and sp. These bacteria were distributed in distinct clusters phylogenitically and showed diverse antifungal activity.

CONCLUSION

The results suggest the potential of soil-derived species as promising antifungal agents. Further studies are recommended to identify their inhibitory metabolites, their ability as biocontrol agents against soil habitated fungi and to explore their mechanism of action and spectrum of activity.