Microbial Biosurfactants: the next generation of biobased functional amphiphiles

Microbial amphiphiles, known as microbial biosurfactants, are key molecules for the future of surfactants and amphiphiles, not only for their sustainable process of synthesis and production but also for their chemical functionalities. Due to more and more stringent EU regulations, multinational chemical companies like Evonik and BASF [1] develop strategic production and partnerships for a long-term investment in this field. Why?

Their phase behaviour in water is both rich and astonishing because of their responsiveness to external stimuli. [2] Introducing responsive chemical groups in classical amphiphiles generally requires a tedious number of chemical steps, while microbial biosurfactants naturally have freely accessible chemical functions, which can be exploited as such, but also further modified through very simple chemical steps, so to broaden the family of active compounds. [3]

Knowledge of the phase behavior and solution properties of surfactants is critical to conceive their application plan, as done for classical surfactants and lipids in the past fifty years. However, the study of the phase behaviour of microbial biosurfactants is only a recent trend in the field. [2] Recent studies from our and other groups have indeed shown the dual surfactant-lipid nature of these molecules. The properties of these molecules are in fact quite astonishing and in this communication, I will highlight a broad set of examples in the field of colloid science and soft matter: fibrillar and lamellar, as well as pH- and metal-responsive hydrogels, soft solid foams, complex coacervation, surface self-assembly and surface antimicrobial properties.

Keywords: Biosurfactants, Microbial amphiphiles, Microbial Surfactants

References

[1] https://corporate.evonik.com/misc/micro/biosurfactants/index.en.html ;

https://www.basf.com/global/en/who-we-are/sustainability/whats-new/sustainability-news/2021/basf-strengthens-position-in-biosurfactants-for-personal-care-home-care-and-industrial-formulaters-with-distinct-partnerships.html

[2] N. Baccile, C. Seyrig, A. Poirier, S. Alonso-de-Castro, S. Roelants, S. Abel, Green Chem., 2021, DOI: 10.1039/d1gc00097g

[3] N. Baccile, E. Delbeke et al. J. Phys. Chem. B, 2019, 123, 3841–3858