Lipopeptide biosurfactants from microbes as multifunctional natural products

Microbial lipopeptides are a unique class of natural biosurfactants with diverse structures and wide-ranging biological activities. These bioactive agents are predominantly produced by bacteria and fungi and exhibit a broad spectrum of bioactivities such as antimicrobial, antifungal, antiviral, anti-inflammatory, anticancer, and immunomodulatory. This review focuses on structural diversity, self-assembly behaviour, and surface active properties of the lipopeptides, with a special focus on the lipopeptides surfactin, iturin, fengycin, and their analogues. The mechanisms of action and the dynamic interactions between lipid and peptide components that determine the specific physicochemical properties and bioactivities of lipopeptides have been analyzed and discussed. Beyond therapeutic potential, lipopeptides also play roles in bioremediation, sustainable agriculture, and food preservation. Despite lipopeptides appear to provide a promising alternative to synthetic surfactants, their use in a commercial setting is currently limited by the difficulties associated with their large-scale production, stability, and toxicity. In this regard, this review aims to provide a summary of the lipopeptides that have been patented for commercial use and critically evaluate recent developments in the discovery and optimization of lipopeptides. A dedicated section on challenges, limitations, and future perspectives further outlines key bottlenecks and emerging research directions in this field. In this way, the review emphasizes the importance of a bioprospecting approach in the translation of microbial lipopeptide biosurfactants into a commercial setting.