Sophorolipid Modification: The Power of Yeasts and Enzymes

Sophorolipids are biosurfactants or biological detergents composed of a hydroxylated fatty acid and the glucose disaccharide sophorose. These commercially relevant molecules are produced by the yeast Starmerella bombicola and offer a green and renewable alternative for traditional surfactants. To further broaden up the application potential of sophorolipids, introduction of structural variation is essential as this influences their physicochemical and biological properties. However, creating molecular variants is not as straightforward as for petrochemically derived surfactants. This is, on the one hand, a consequence of the biological origin and restricting biochemistry behind it, and is, on the other hand, caused by the complexity of chemical processes regarding the necessity of protection and deprotection of the glucose units. In this chapter, several strategies to overcome these limitations will be discussed, such as the use of special substrates during yeast cultivation, design of engineered strains, and enzymatic modification.