Optimized pulse?feeding fed?batch fermentation for enhanced lignin to polyhydroxyalkanoate transformation
With an anticipated growth of Bio?Circular?Green economy, the amount of lignin generated as by?product from biorefineries is increasing. Hence, lignin valorising strategies become a very interesting option to improve economic viability of the biorefineries. This study revealed the development of bioprocesses for upgrading lignin into bioplastic. Specifically, a novel strain of Pseudomonas fulva has been applied for microbial bioconversion of organosolv lignin to fermentative polyhydroxyalkanoate (PHA) production. Fed?batch fermentation of lignin?to?PHA with pulse?feeding approach was optimized using Design of Experiment. Effects of C:N ratio and feeding profiles on PHA accumulation in P. fulva were investigated to determine optimal operation. Under optimized fed?batch, the PHA concentration of 195.2?±?6.6 mg/L could be reached and the PHA content was more than 2 folds enhancement compared to batch process. Type of PHA produced was also characterized for chemical composition via GC–MS analysis. The established lignin to PHA conversion could provide platform for developing integrated lignin bioprocessing to promote cost?effective biorefineries.