Abstract
Mannosylerythritol lipids (MELs), which are amphiphilic glycolipids abundantly produced by yeasts from renewable resources, are one of the most promising biosurfactants because of their excellent surface-active properties and versatile biochemical activities. However, the structural variety of MELs hitherto discovered still remains limited; this makes the broad range of their applications difficult. We thus have been continuously developing new types of MELs with different structures and functions. Recently, we found that novel types of MELs, namely the tri-acylated and mono-acylated MEL, were preferentially obtained by the selection of cultural conditions, respectively. They have different hydrophobic structures and show different interfacial properties compared to the conventional di-acylated MELs. These MEL derivatives show wide hydrophilic-lipophilic balance (HLB) values, and the combination of them makes the wide range of applications possible. On the other hand, we found new MEL derivatives having the carbohydrate configuration different from the conventional MELs, which were selectively produced by specific yeast strains. These new diastereomers show different self-assembling properties and biological actions, and their application to pharmaceutical and cosmetic fields are expected. This study provides these novel MEL derivatives and the methods of their tailor-made production.
