Monday, May 4, 2009
11-08
High production of 1,3-propanediol from crude glycerol using suspended and immobilized Klebsiella pneumoniae
Sun-Ae Jun1, Chuloo Moon1, Cheol-Hee Kang2, Byoung-In Sang1, and Youngsoon Um1. (1) Center for Environmental Technology Research, Korea Institute of Science and Technology, 39-1 Hawolgok, Sungbuk, Seoul, 136-791, South Korea, (2) INWOO corporation, Weedang Bldg, Bangiee-Dong, Songpa-Gu, Seoul, South Korea
In this study, the production of 1,3-propanediol (1,3-PD) was investigated with Klebsiella pneumoniae DSM2026 using crude glycerol solution obtained from two different biodiesel production processes. Crude glycerol was utilized without purification to investigate an inhibitory effect of crude glycerol on 1,3-PD production when compared to pure glycerol. In the media containing pure or crude glycerol, K.pneumoniae DSM2026 could biosynthesize 1,3-PD with the yield higher than 0.5 g/g. The yields of 1,3-PD production from crude glycerol solutions (90% and 70% glycerol-containing biodiesel wastes) were even higher than those obtained with commercially available glycerol (pure glycerol) in batch and fed-batch cultures. In fed-batch cultures, more than 80 g/L of 1,3-PD was produced with crude glycerol. To our knowledge, this is the highest 1,3-PD concentration reported so far using crude glycerol. Based on the optimum culture conditions obtained, a fed-batch fermentation with the cell immobilization system was performed in a bioreactor to enhance 1,3-PD production. The effect of additional vitamin B12, a co-enzyme for glycerol dehydratase, was also investigated with the cell immobilization system. Cultures utilizing crude glycerol in the immobilization system showed even more effective 1,3-PD production than that with pure glycerol. Further study will be performed to separate 1,3-PD directly from bioreactors to prevent product inhibitory effect.