Investigation of the mechanisms and optimal conditions during microbial pretreatment of lignocellulose biomass by using co-cultures.

Pretreatment of lignocellulose biomass is necessary to degrade the lignin, decrease the cellulose crystallinity and increase the surface area for the subsequent required enzymatic hydrolysis. Fungal pretreatment is based on solid state cultivation where the fungal mycelia penetrate and attack the solid substrate through direct contact by releasing ligninolytic enzymes. In this project the mechanisms and optimal conditions of this complex process are investigated to enable a decrease in pretreatment time by using a stable consortium of collaborating microorganisms. Separate fungal strains are growing on polar wood chips in a computer controlled solid state fermenter. The process is followed up by measuring the deligninolytic enzyme activities, cellulase activities, carbohydrate concentrations in order to evaluate the capabilities of each strain. Also the growth rate will be determined by measuring the oxygen uptake rate of the solid state culture. All acquired information will be important to select the right strains that will enable a microbial consortium where a synergetic cooperation with high lignin removal will be obtained. This final pretreatment efficiency will be evaluated on ethanol productivity in a simultaneous saccharification and fermentation process of the pretreated poplar wood.

Keywords:FERMENTATION, SOLID STATE FERMENTATION, LIGNOCELLULOSE, ENZYMES

Disciplines:Biochemistry and metabolism, Microbiology, Systems biology, Catalysis and reacting systems engineering, Chemical product design and formulation, General chemical and biochemical engineering, Process engineering, Separation and membrane technologies, Transport phenomena, Other (bio)chemical engineering, Laboratory medicine, Medical biochemistry and metabolism