(546g) Process Development and Scale-up of Ionic Liquid-Tolerant Cellulase Cocktail

Title: "Process development and scale-up of ionic liquid-tolerant cellulase cocktail�
F. Tachea1, C.Li1, L. Sandoval1, S Hubbard1, Q.He1, J. Wong1, P. Coffman1, J. Gardner1, J. Baez1, and J.
Gladden2
The availability of lignocellulose biomass makes it a promising feedstock for commercial scale production of biofuels. However, current commercial enzyme cocktails are less efficient and more expensive to make fermentable products from lignocellulose biomass. Researchers at the Joint
BioEnergy Institute (JBEI) have identified a novel ionic liquid (IL) tolerant cellulase cocktail called JTherm, a mixture of recombinant β-glucosidase (BG), cellobiohydrolase (CBH) expressed in E.Coli and endoglucanase/xylanase produced from a thermphilic Bacterial Community, which can efficiently break down the IL pretreated cellulosic biomass to fermentable sugars. In collaboration with JBEI, the Advanced Biofuels Process Demonstration Unit (ABPDU) is performing process optimization and development of the JTherm enzymes at 2L scale. At the ABPDU before scaling up the JTherm cellulose enzyme cocktail, process scale up parametersâ?? were defined at 2L scale and all the scale up issues were resolved. In addition, a fed-batch fermentation process was developed for both BG and CBH enzymes and the biomass growth and enzyme expression were investigated in complex, defined and auto- induction medium. Moreover, the effect of early and late IPTG induction on biomass growth and
enzyme expression was investigated. Based on these studies, we were able to improve the BG biomass growth about 80% and employing the fed-batch fermentation improves the activity of the enzymes. More findings are underway for the 300 L scale fermentations, and the knowledge gained from these scale up studies is an essential step for demonstrating the commercial viability of the enzyme technology for biofuels production.

1Advanced Biofuels Process Demonstration Unit, Lawrence Berkeley National Laboratory, Emeryville, CA;

2Joint BioEnergy Institute, Emeryville, CA