Extractive fermentation for improved production and recovery of lipase derived from Burkholderia cepacia using a thermoseparating polymer in aqueous two-phase systems

► Lipase was produced using thermoseparating reagent in extractive fermentation. ► Ten consecutive batches of fermentations were performed in this study. ► A high purification factor (14) and yield (99%) were achieved. ► The extractive fermentation has the potential to improve lipase production. An extractive fermentation technique was developed using a thermoseparating reagent to form a two-phase system for simultaneous cell cultivation and downstream processing of extracellular Burkholderia cepacia lipase. A 10% (w/w) solution of ethylene oxide–propylene oxide (EOPO) with a molecular mass of 3900g/mol and pH 8.5, a 200rpm speed, and 30°C were selected as the optimal conditions for lipase production (55U/ml). Repetitive batch fermentation was performed by continuous replacement of the top phase every 24h, which resulted in an average cell growth mass of 4.7g/L for 10 extractive batches over 240h. In scaling-up the process, a bench-scale bioreactor was tested under the conditions that had been optimized in flasks. The production rate and recovery yield were higher in the bioreactor compared to fermentation performed in flasks.