Enhanced Production of 1,3-Propanediol by Glycerol Fermentation Using an Attached-to-Silicone Biofilm Reactor

Abstract

Glycerol fermentation for 1,3-propanediol (1,3-PDO) production was studied in an anaerobic up-flow reactor with biomass attached to silicone support. A mixed microbial culture was activated to perform the biofilm formation and attachment to a silicone hose prior the reactor operation. The reactor was operated over 362 days divided into two phases (P). In P1 and P2, the reactor was continuously fed with pure and crude glycerol, respectively. The operation consisted of increasing the glycerol loading rates (gly-LR). The achieved highest 1,3-PDO average yields were 0.43 mol mol-gly−1 and 0.62 mol mol-gly−1 when applied gly-LR was 18 and 46 g L−1 d−1 in P1 and P2, respectively. A maximum 1,3-PDO productivity of 14.7 g L−1 d−1 was obtained in P2. The higher yields of 1,3-PDO when the feed changed from pure to crude glycerol indicated a change in the microbial community. These results show that the studied system can be very promising and cost-effective for converting crude glycerol into value-added products on large scale even at high loads. Graphical Abstract