Fig. 3

Adsorption isotherms of cellulase on cellulolytic enzyme lignin materials derived from acid and alkali pre-treated corn stover. The adsorption experiments were performed by mixing CEL (solid loading at 1%), enzyme (cellulase loading at 25–2000 μg/mL) and 50 mM sodium citrate buffer (pH 4.8) at a total volume of 2 mL, followed by incubation at 4 °C for 60 min to reach equilibrium. Error bars represent standard errors