The yeast Candida bombicola ATCC 22214 is well-known to produce mixtures of glycolipids containing the sugar sophorose, the so-called sophorolipids, especially when cultivated on hydrophobic carbon sources as co-substrates. To improve cultivation efficiency, an integrated process was developed using ultrasound separation technology. Since this technology is new for use with C. bombicola, it was first characterized in batch experiments and afterwards implemented in an integrated production process. In this process, separation efficiencies of about 99% C. bombicola cells could be achieved, leading to 8 g/L of nearly cell-free sophorolipid product and a total amount of 73.8 g/L sophorolipids. Furthermore, a technical mixture of unusual branched fatty alcohols containing mainly 2-hexyl-1-decanol was used as co-substrate with glucose in a shake flask study. This resulted in the production of a new product, 1-O-b-glucopyranosyl-2-hexyldecanol, a molecule containing glucose as the sugar moiety and 2-hexyl-1-decanol as a branched hydrophobic side chain.

The soil bacterium Tsukamurella spec. DSM 44370 produces a mixture of oligosaccharide lipids when cultivated on sunflower oil. In contrast cultivation with calendula oil as carbon source afforded a different product composition with overproduction of 2,3-di-O-acyl-ß-Dglucopyranosyl-(1-2)-ß-D-galactopyranosyl-(1-6)-4,6-di-O-acyl-α-D-glucopyranosyl-(1-1)-α-Dglucopyranose (GL 3) that amounted to 60 % of the whole product. GL3 and its parent tetrahexose backbone G 3 were then modified enzymatically with the lipase Novozyme 435 from Candida antarctica by addition of one and two oleic acid molecules to GL3 and four molecules to G 3. The new glycolipids were shown to exhibit interesting surface activities compared to commercially available products, decreasing the surface tension of water to 23 mN/m. In addition these products showed novel biological activities through the inhibition of the activation of Epstein-Barr virus early antigen.

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