Enzymes for 2G Sugars
Acronym: 2GEnzymes

- Tino Elter - Fraunhofer Center for Chemical-Biotechnological Processes CBP - Germany
- Juan Lema - University of Santiago de Compostela - Spain
- Matti Heikkilä - MetGen Oy - Finland
- Christian Wilhelm - University Leipzig - Germany

The ambition of this project is to design a new integrated process for the production of second generation sugars (2GS) using ligninolytic enzymes (LE) and novel cellulases (CA). Basis for the generation of 2GS is the organosolv process of Fraunhofer CBP which allows the fractionation of lignocellulosic material into cellulose, hemicellulose and lignin. This is carried out under relatively severe conditions and requires the use of energy, chemicals and specialized equipment. The resulting cellulose is hydrolyzed enzymatically to glucose. The innovative idea lies in the combined application of CA and LE in both steps of the 2GS production. The application of LE before and during wood fractionation will lead to a reduced consumption of energy and chemicals by using less severe conditions in the pretreatment and to lower lignin contents in the resulting cellulose fraction. In the hydrolysis step CA and LE will be applied simultaneously to the resulting fibers. This will lower inhibitory effects of lignin on CA and will likely lead to higher yields of fermentable sugars. Also lower necessary CA concentrations and a faster reaction are expected. As LE have already been used to detoxify 2GS, it is also expected to improve the fermentability of the gained sugars. Another aspect is the use of novel CA from Penicillium verruculosum. This cellulase is favored for saccharification of pulp because of the higher content of ß-glucosidase and the tolerance towards CA inhibitors compared to commercial enzyme preparations. It is intended to integrate CA production into the overall process from lignocellulosics to 2GS by using cellulose from the wood fractionation as substrate. We further aim to improve our production strain genetically to optimize the production of cellulolytic enzymes by P. verruculosum. Finally, the modified organosolv process as well as the optimized CA fermentation process is demonstrated in pilot scale to obtain scale-up data for an industrial relevant scale.