Effect of Carbon Source on the Antifungal Activity of Lipopeptides Produced by Bacillus licheniformis SCV1 Against Trichophyton rubrum and Trichophyton mentagrophytes.

Biosurfactants are amphiphilic metabolites with antimicrobial properties, with their synthesis contingent upon the media utilized. This study investigated the antifungal activity of the biosurfactant generated by Bacillus licheniformis SCV1 grown in a mineral salt medium with various carbon sources. The research demonstrated that biosurfactants derived from media with several carbon sources, including glucose, glycerol, sucrose, starch, and mannitol, exhibited different antifungal efficacy against fungal pathogens, namely Trichophyton mentagrophytes and Trichophyton rubrum. The biosurfactant derived from the production medium containing glycerol as a carbon source showed superior antifungal efficacy against both fungi compared to biosurfactant produced from media with other carbon sources. FTIR and LC-MS analyses of the biosurfactants indicated that they are lipopeptides comprising of surfactin, iturin, and lichenysin subtypes. The lipopeptides produced using from various carbon sources exhibited structural variations in their fatty acyl chains. The biosurfactant derived from glycerol containing production medium was observed to include lipopeptides with extended fatty acyl chains, potentially contributing to its superior antifungal efficacy. Hence, this study emphasizes the significance of selecting an appropriate medium for generating biosurfactants with optimal activity against infections.