Enzyme production, growth, and adaptation of T-reesei strains QM9414, L-27, RL-P37, and Rut C-30 to conditioned yellow poplar sawdust hydrolysate - Scientific note

National Renewable Energy Laboratory (NREL) has developed a conditioning pr ocess that decreases acetic acid levels in pretreated yellow poplar hydroly sate. Trichoderma reesei is sensitive to acetic acid and this conditioning method has enabled applied cellulase production with hardwoods. T. reesei s trains QM9414, L-27, RL-P37, and Rut C-30 were screened for growth on condi tioned hydrolysate liquor. Tolerance to hydrolysate was found to be strain- dependent. Strain QM9414 was adapted to grow in 80% (v/v) conditioned hydro lysate (40 g/L of soluble sugars and 1.6 g/L acetic acid from pretreated po plar). However, enzyme production was highest at 20% (v/v) hydrolysate usin g strain L-27. Cellulase titers of 2-3 International Filter Paper Units (IF PU)/mL were achieved using pretreated yellow poplar liquors and solids as t he sole carbon sources.