On the use of waste frying oil in the synthesis of sophorolipids

Sophorolipids are surface-active agents which are synthesised by the yeast Candida bombicola. Here we present the possibility of reducing the economical and ecological cost of producing sophorolipids by using waste frying oil as a substrate for C. bombicola. A comparison is made between two grades of biodiesel, waste frying oil and the methyl ester of coco/palm oil as lipophilic substrates on a shakeflask level. Cultivations in a bioreactor using waste frying oil as a substrate were carried out. A new strategy for product recovery without the use of organic solvent is also proposed. The work presented here investigates whether it is possible to produce sophorolipids on waste frying oil and recover the product without using organic solvents.