Enzymatic hydrolysis was carried out using xylanase, to remove
the hemicelluloses and lignin fractions. The light yellowish pulp
became lighter, but not totally white (Fig. 1b), so the process did not
remove the lignin fractions completely. Probably, the alkaline treatment
probably was not efficient enough to totally remove lignin; the
remaining lignin may have formed a barrier around hemicelluloses
and cellulose. In other words, the enzyme xylanase had difficulty in
solubilizing hemicelluloses, so it was not able to penetrate the cellulose
chains,whichmade cellulose hydrolysis difficult. Comparedwith
ET, CT involved more steps and was more aggressive, promoting
greater removal of the amorphous components.
The concentration of nanofibers in the suspensions (g of nanofibers/
100 g of suspension) obtained from CT and ET was 0.54 and
0.57, respectively. Regarding nanoparticles yield, ET furnished twice
as high yield (10%) as CT (5.1%). The extra steps performed during
CT probably culminated in greater sample loss.