Production of surfactin from novel Bacillus spp. isolated from soil and its antifungal properties

Abstract

Aim: This research aimed to screen the biosurfactant-producing bacteria from soil, especially for the betterment of the environment in terms of bioremediation and biodegradation of lipids and hydrocarbons. Methodology: Bacillus spp. isolated from the soil was cultured and inoculated into different mineral media such as Glucose, Sawdust, and Bagasse mineral media. The surfactin was extracted and the activity was studied using oil emulsification test, oil spreading assay, and drop collapse assay. Bacillus spp. that provided better results were sequenced and submitted to NCBI. The surfactin of the specific bacteria was characterized using TLC, UV-vis spectra, and FTIR analysis. Finally, the antifungal activity assay was performed against Aspergillus flavus, Rhizopus spp., and Aspergillus niger. Results: Bacillus species subjected to gene sequencing was identified as Bacillus mycoids strain ARJCBNR (On464184). UV-vis spectra and FTIR analyses revealed various functional groups such as 3356.14 cm-1 (N-H stretch), 1635.64 cm-1 (C=O amide), and 1211 cm-1 (C-O stretch) representing the surfactin compound between 4000 and 500 cm-1. Upon antifungal activity, sawdust-extracted surfactin had a higher zone of inhibition against all the tested fungi. Interpretation: This study revealed that Bacillus spp. can utilize agro-industrial waste as substrate to produce surfactin. Also, the surfactin extracted from sawdust mineral media showed higher antifungal activity. Key words: Bacillus spp., Biosurfactant, Mineral media, Soil, Surfactin