Ionic liquid pretreatment of lignocellulosic biomass shows great potential in effectively reducing the biomass recalcitrance with less enzyme requirement for saccharification of biomass into sugars. However, commercially available cellulase enzymes are sensitive to residual ionic liquids from pretreatment necessitating extensive and expensive washing steps to remove ionic liquids from pretreated material. As a result, high costs associated with the extensive pretreatment process followed by washing and separate hydrolysis has become one of the main barriers for commercialization. Consolidation of pretreatment and enzymatic saccharification would address the current techno- economic challenges related to high cost of separate pretreatment and saccharification. To accomplish this, researchers at Joint Bioenergy Institute (JBEI) have developed a thermophilic ionic liquid-tolerant cellulase cocktail called “JTherm” for biofuel production. The cocktail can tolerate up to 20-30% ionic liquid over a range of temperatures, 50-70 deg C, when incubated at pH 5.5 for 72 hours.
In this study, we present the results from the scale-up of production of JTherm cocktail in 75L bioreactors at Advanced Biofuel Process Demonstration Unit (ABPDU). Initial results showed excellent scalability of the process with enzyme yields similar to that of shake flasks and further optimization would expand the cellulolytic enzymes landscape to integrate various ionic liquid pretreatment technologies overcoming barriers to production of economically viable lignocellulosic biofuels.