Mannosylerythritol Lipids: Biosynthesis, Genetics, and Production Strategies
Microbial biosurfactants represent a promising alternative for current petrochemical or oleochemical surfactants. Mannosylerythritol lipids (MEL) are highly promising glycolipids produced mainly by basidiomycetous fungi of the Ustilaginomycetes class. A large variety of structures has already been found in wild-type strains. Moreover, novel structures can be designed by combining different strains and substrates, by genetic engineering or by enzymatic modification. Nevertheless, large-scale production of the different structures in bioreactors leading to higher yields and thus a more economic process still needs to be addressed in more detail. So far, it has only been investigated for two different strains, leaving space for further process optimization. This chapter is intended to give an overview of state of the art from a scientific perspective on mannosylerythritol lipids, focusing on its structural variety and how this can be tailored by employing different microorganisms and cultivation strategies to fit the various fields of application.