Exploring thermophilic biosurfactants: Microbial producers, applications and biotechnological relevance

Biosurfactants (BSs) are microbial amphiphiles that lower surface and interfacial tension and stabilize emulsions, offering a viable, lower-impact alternative to conventional surfactants. Within this family, thermostable biosurfactants (TSBS) extend the operating window wherever heat is intrinsic to the process. Thermophilic/thermotolerant microorganisms remain valuable sources of these molecules and, in some cases, practical production hosts. This review maps where TSBS produced by thermophile strains come from (natural and engineered extreme environments) and synthesizes evidence across application domains: industrial and consumer products, pharmaceuticals and health, agriculture, environmental remediation and resource recovery, and the energy sector. The analysis also consolidates the main bottlenecks that limit broader adoption: specifying stability and performance by use-case, discovery and cultivation of suitable strains (including currently uncultured taxa), bioprocessing choices and constraints, cost and scale-up interdependencies, and integration with circular-economy feedstocks. Emerging directions include guided screening, omics and metabolomics for rapid prioritization, cultivation strategies tailored to extreme niches, targeted pathway/host engineering, fit-for-purpose process design, and standardized performance testing at relevant temperatures. Patent activity underscores sustained industrial interest. Together, these elements outline a pragmatic route to position TSBS as performance-enabling, lower-impact surfactants in heat-involved workflows.