Antifungal activity of Bacillussp. Gn-A11-18isolated from decomposing solid green household waste in water and soil against Candida albicans and Aspergillus niger

Candida albicans an opportunistic pathogenic fungus causes many infections in humans. Whereas Aspergillus niger is a fungus that can produce ochratoxins, a group of extremely dangerous secondary metabolites that are classified as potentially carcinogenic to humans and also causing deterioration in grapes, strawberries, etc. The purpose of the current study is to isolate, purify, identify and characterize new microorganisms associated with solid green household waste for the control of C. albicans and A. niger. The antifungal activity of bacterial isolates was carried out in vitro by the agar plug diffusion method, the disk and well diffusion method. The isolate that showed promising activity has been identified by those macroscopic, microscopic and biochemical characteristics. The results obtained in the course of this study showed the isolation of an isolate named Gn-A11-18, which was shown to have significant inhibitory activity with a 42.66% inhibition percentage against A. niger and a 44.66 mm inhibition diameter against C. albicans compared to the controls. The identification of Gn-A11-18 isolate has shown that this isolate belongs to the genus Bacillus with a similarity to Bacillus subtilis and Bacillus tequilensis. In the light of the results of this study, we can suggest that the bioactive compound of Bacillus sp. Gn-A11-18 could become a biological alternate that could have an important role to fight against C. albicans and A. niger.