Construction of a whole-cell catalyst displaying a fungal lipase for effective treatment of oily wastewaters

To combine the advantage of the oleaginous yeast Yarrowia lipolytica with the high activity of some fungal lipases for oily wastewater treatment, an effective lipase-displaying arming yeast was constructed using the flocculation functional domain of Saccharomyces cerevisiae as the protein anchor. To estimate the effect of the whole-cell oily wastewater treatment, the lipase-displaying arming yeast was added into an open activated sludge bioreactor. Within 72 h of whole-cell treatment, 96.9% of oil and 97.6% of chemical oxygen demand (COD) were removed, while only 87.1% of oil and 91.8% of COD were removed in control A (Y. lipolytica Polg was added), 45.1% of oil and 67.5% of COD were removed in control B (no cell was added) in 72 h. The lipase-displaying arming yeast exhibited remarkable oil removal and COD degradation effect compared with the control samples, exemplifying its application potential.