Sophorolipids, commercialized glycolipid biosurfactants: Derivatives, component analysis, and applications

Biosurfactants contain various kinds of compounds and have complex structures because they are derived from microorganisms. Sophorolipids (SLs) are biosurfactants that are being commercialized. However, there are issues with fermentation technology and interface science due to the presence of many derivatives, which has become a bottleneck for the commercial expansion of SLs. This review addresses this issue. First, SL derivatives are described, including acid, lactone, bola, and glyceride forms. Then, the yeasts that produce various SL derivatives are described. Next, methods for measuring SL concentrations and component ratios are described, including high‐performance liquid chromatography with methanol. Finally, their applications in toiletries, cosmetics, medicine, livestock, agriculture, and the environment are described, and we discuss the importance of measuring SL concentrations and derivative ratios as technical challenges to revitalize the SL market.