Preparation and characterization of the spherical nanosized cellulose by the enzymatic hydrolysis of pulp fibers

In this work, the pulp fibers were enzymolyzed to prepare the nanosized cellulose (NC). The as-prepared samples were characterized by optical microscopy, electron microscopy, and Raman spectra. The experimental results indicated that enzymatic hydrolysis of pulp fibers could produce the spherical NC with a mean particle size of about 30 nm, which had the excellent monodispersity and uniformity. When the concentration of complex enzymes was 20 u/mL (cellulase: xylanase = 9: 1), the yield of NC was 13.6%. The single cellulase was used, even if the enzyme concentration reached up to 200 u/mL, only a mixture of strip and granular flocculation were obtained. The positive synergistic effect between xylanase and cellulase could be due to the enzymolysis of hemicellulose located on the cellulose microfibers to be favorable of cutting and splitting of the microfibers by the endoglucanase in cellulase.