New miniature stirred-tank bioreactors for parallel study of enzymatic biomass hydrolysis

Many factors strongly influence the enzymatic hydrolysis of biomass to fermentable sugars (feedstock composition, pretreatment, enzymes and enzyme loading). In order to optimize the reaction conditions for the hydrolysis of biomass, an accurate high-throughput bioprocess development tool is mandatory, which enables a parallelization and an easy scale-up. New S-shaped impellers were developed for magnetically inductive driven stirred-tank bioreactors at a 10 mL-scale. An efficient and reproducible homogenization was shown at 20% w/w solids loading of microcrystalline cellulose and at, 4–10% with wheat straw in 48 parallel operated stirred-tank bioreactors. The scale-up was successfully validated for the enzymatic hydrolysis of wheat straw suspensions and microcrystalline cellulose mixtures by application of a cellulase complex at a milliliter- and liter-scale. As an example, the parallel stirred-tank bioreactor system was applied for the evaluation of enzymatic batch hydrolyses of plant materials with varying pretreatments.

► Miniature 48-fold parallel reactor system for the enzymatic conversion of plant materials up to the millimeter scale.
► 48-Fold parallel stirred-tank bioreaction system uses a completely new impeller.
► Enzymatic biomass hydrolysis combined with reliable high-throughput bioprocess design.
► Biomass content at a 10 mL scale comparable to liter scale.
► Scale up based on fundamental studies like power consumption and mixing characteristic.