TY - JOUR U1 - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed) A1 - Zerhusen, Christian A1 - Bollmann, Timo A1 - Gödderz, Andreas A1 - Fleischer, Peter A1 - Glüsen, Birgit A1 - Schörken, Ulrich T1 - Microbial Synthesis of Nonionic Long‐Chain Sophorolipid Emulsifiers Obtained from Fatty Alcohol and Mixed Lipid Feeding JF - European Journal of Lipid Science and Technology N2 - Starmerella bombicola is known to produce sub‐terminally hydroxylated lactonic sophorolipids (SLs), while Candida kuoi synthesizes acidic open chain SLs with terminally hydroxylated fatty acids. Upon feeding glucose and fatty alcohols both strains form long‐chain nonionic SLs. According to structure elucidation the SLs consist of a hydroxylated fatty acid esterified with fatty alcohol and linked via a glycoside bond to the diacetylated sophorose unit. Palmityl, stearyl, and oleyl alcohols lead to products with lipid chain lengths of C32 or C36. Oleyl alcohol is the preferred substrate leading to 45 g L−1 of the double unsaturated C36 SL with S. bombicola and 20 g L−1 with C. kuoi. Scale up from shake flask to 1.5 L fermentations is possible and 65 g L−1 long‐chain SLs are obtained with S. bombicola within 7 days. Mixed feeding of oleic acid and a variety of fatty alcohols leads to new long‐chain SLs. In the presence of oleic acid the yeasts do not oxidize the fatty alcohol and thus the production of biosurfactants with tailored chain length is possible. The long‐chain SLs show good emulsification ability of water/paraffin oil mixtures at low energy input and reduced interfacial tension significantly. Practical Applications: Sophorolipids are produced by fermentation on industrial scale focusing on cleaning and detergent applications. Mainly lactonic or anionic open‐chain forms are used today. The new long‐chain SLs presented in this manuscript are accessible with existing production technology and can be produced with high titers from cost‐efficient renewable raw materials. In contrast to the commercial products the long‐chain SLs are more hydrophobic and exhibit a strong emulsification behavior. Therefore they have the potential to broaden the application range of SLs in future. They may be useful as novel emulsifiers for cosmetic creams and lotions, pharmaceutical ointments and food products or may find application in oil spill remediation. KW - Biotensid KW - Biosurfactants KW - Emulsifiers KW - Fatty alcohols KW - Sophorolipids KW - Emulgator KW - Fettalkohole Y1 - 2019 UN - https://nbn-resolving.org/urn:nbn:de:hbz:832-epub4-15799 U6 - https://doi.org/10.1002/ejlt.201900110 DO - https://doi.org/10.1002/ejlt.201900110 VL - 122 IS - 1 SP - 12 S1 - 12 ER -