Table 5.

Factors that limit hydrolytic efficiency of cellulase on cellulose surface.

Factor 1 Biomass structural features	Factor 2 Enzyme mechanism
(I) Physical structure Accessible surface area, crystallinity, physical distribution of lignin in the biomass matrix, degree of polymerization, pore volume, and biomass particle size (II) Chemical structure Compositions of cellulose, hemicellulose (xylan), lignin, and acetyl groups bound to hemicellulose	(I) Enzyme diffusion and accessibility (II) Selectivity of enzyme to component in cellulose fiber (III) Enzyme inhibitor