Production of Sophorolipids from Candida bombicola ATCC 22214 Using Turkish Corn Oil and Honey

The ability of Candida bombicola ATCC 22214 to produce sophorolipids using Turkish corn oil and honey was investigated. Shake flask experiments were carried out both with and without the addition of glucose as the second carbon source. The organism could produce sophorolipids under both conditions but higher production was obtained when corn oil was combined with glucose. The 3 L bioreactor was first operated in batch mode, using both corn oil and glucose. When all the glucose was consumed, 1/4th of the broth was pumped out and was replaced by freshly prepared medium containing 10 % [w/v] of cheap market honey as the sole carbon source. Feed was comprised of corn oil. High concentrations of sophorolipids (> 400 g/L) were produced. The crude products obtained from the batch cultivation could be solidified as very light brown solids when unused oil was removed by hexane, while the products of the two‐stage cultivation remained as viscous, honey‐like liquids after identical treatments. Surfactants are indispensable components of daily life. Most surfactant molecules are chemically synthesized and, unfortunately, have a negative impact on the environment since they are not biodegradable and cause high aquatic toxicity. Biosurfactants – green biodegradable surfactants – should replace their synthetic equivalents. As the only disadvantage of biosurfactants is their high price, this paper focuses on a way to reduce production costs by selecting inexpensive medium components.