The possible reason for this discrepancy could be differences in the feedstock characteristics used for incubation or the heat resistance capacity of the E. coli strains used by Aitken et al. (2007).
This difference in enzymatic yields can be attributed to difference in the feedstocks: corn stover (Kazi et al. [ 29]) and Tall Fescue (present study).
We observed only punctual differences between the feedstocks regarding the contaminants.
In addition to feedstock price, higher ethanol prices predicted in the present study can be attributed to the differences in feedstocks, pretreatment technology, onsite/off site cellulase enzyme production, SSF/SSCoF/Consolidated bioprocessing, short/medium/mature technology scenarios and solid content of process streams.
However, the differences in CO2 production rates observed for the different piles show that the rates may have been affected by the differences in the easily biodegradable materials and the feedstock ratios.
The ash buffering effect could also be explained by differences in the buffering capacities of the different feedstocks and mixtures.
The primary differences in managing woody feedstocks for bioenergy production vs for pulp/sawtimber production include a higher frequency of pesticide and fertilizer applications, whole-tree removal, and greater ground disturbance (i.e., more bare ground during stand establishment and more frequent disturbance).
Regardless of the substantial differences in the source, structure and chemical composition of the feedstocks, and the difference in the pretreatment technology used, the protein loading required to achieve efficient hydrolysis of lignocellulosic substrates was strongly dependent on the accessibility of the cellulosic component of each of the substrates.
With careful selection of experimental conditions in each of the two assays, and with a good understanding of the agronomic backgrounds (pedigree) of the samples, the assay can be a powerful tool to investigate differences in cellulosic feedstock samples.
Interestingly, we also noticed several feedstock-specific gene responses that may shed light on inherent chemical differences in the plant biomass.
