Lopez et al. (2004) isolated and identified new microorganisms for biological treatment of lignocellulosic hydrolysates. Several isolates with potential for abatement of inhibitors from complex fermentation substrates were obtained from soil by enrichment procedure, and selected according to their potential for depletion of toxic compounds from acid-pretreated hydrolysates. The selection was carried out in a defined mineral medium containing a mixture of ferulic acid, 5-hydroxymethylfurfural (5-HMF), and furfural as the carbon and energy sources, followed by an additional transfer into a corn stover hydrolysate (CSH) prepared using a dilute acid. Six isolates, including five bacteria related to Methylobacterium extorquens, Pseudomonas spp., Flavobacterium indologenes, Acinetobacter spp., Arthrobacter aurescens, and one fungus, C. ligniaria, were chosen based on stable growth on the above substrates. All six isolates depleted toxic compounds from the medium, but only C. ligniaria C8 (NRRL 30616) was effective at metabolizing furfural and 5-HMF as well as aromatic and aliphatic acids, and aldehydes (Lopez et al. 2004; Nichols et al. 2008- . This strain removed 78% of 5-HMF and 97% of furfural, while overliming only decreased 51% of the total furans (Martinez et al. 2001- . The possibility of including biological detoxification with C. ligniaria C8 in a biomass-to-ethanol conversion process with S. cerevisiae was tested at laboratory scale. The treatment of hydrolysate with C. ligniaria C8 also resulted in improved metabolism of pentoses by a recombinant bacterial strain, E. coli FBR5 (Nichols et al. 2008). The E. coli FBR5 has a native ability to ferment glucose, xylose, and arabinose, and carries recombinant genes for selective production of ethanol. All sugars in hydrolysates treated with C. ligniaria C8 were consumed more quickly by the E. coli FBR5 than sugars in untreated hydrolysates.