Multi-component phase behavior of biosurfactants

The public increasingly requests green formulations as a consequence of growing sustainability awareness. This may include glycolipid and lipopeptide biosurfactants (BS), which are considered renewable, biodegradable, and mild alternatives to conventional fossil-based surfactants. For developing green formulations, it is crucial to understand the phase behavior and the resulting physico-chemical characteristics of systems with BS. This is not only necessary for binary systems of BS in water, which have already been frequently studied and reviewed. But it is also important to study combinations with other surfactants and oils due to their higher relevance for applications. For this reason, we review in this article the different types of phase behavior of systems comprising BS, in particular systems with rhamnolipid, sophorolipid, mannosylerythritol lipid, cellobiose lipid, and surfactin.