High efficiency succinic acid production from glycerol via in-situ fibrous bed bioreactor with an engineered Yarrowia lipolytica

Abstract

Fibrous-bed bioreactor (FBB) has been developed to high density culture of anaerobic microorganism for long-term continuous production of chemicals or biofuels[1,2]. Our previous study has demonstrated that Yarrowia lipolytica has strong ability to produce succinic acid (SA) by metabolic engineering approaches[3]. The aim of this research is to demonstrate an in situ fibrous-bed bioreactor fermentation strategy for enhancing SA productivity using aerobic yeast. Firstly, contrast between free-cell and FBB fermentation was performed to prove the feasibility of using FBB to improve SA production. Then, different fermentation had been investigated to obtain optimal operation conditions. Finally, repeated batch fermentation was conducted to test the operational stability of the FBB. Under the optimized conditions, an average productivity of 1.29 g/(L*h), about 82% higher than the free cell fermentation was obtained. The yield of SA is 0.30 g/g, which is 7% higher than the free cell fermentation. The results indicated that the FBB design has a great potential to improve the SA productivity in aerobic yeast fermentation.