Note: a the main wave numbers obtained in the present
study; b the main wave numbers reported in the
literature [30-34]; c functional
groups; d molecules of the functional groups. CWM,
cell wall material; CDTA, 2-cyclohexanediamine-N,N,N’,N ’-acetic
acid; C, cellulose; P, pectin; XG, xyloglucan.
The effect of different extraction conditions (solid-liquid ratio,
enzyme concentration, enzyme hydrolysis temperature, and enzyme
hydrolysis time) on FT-IR spectra of celluloses are presented in Fig. 2.
The main characteristic wave numbers of cellulose remained unchanged
under different extraction conditions, but the absorbance, which denotes
the content of
characteristic
wave numbers, varied significantly. Examples of FT-IR spectra of
cellulose under different
solid-
liquid ratio are shown in Fig. 2a, cellulose had same characteristic
wave numbers. However, characteristic bands of celluloses at solid-
liquid ratio 1:3, 1:4, and 1:5 were sharper and more intensive compared
to that at solid- liquid ratio 1:2. The
solid-
liquid ratio, enzyme concentration, enzyme hydrolysis temperature, and
enzyme hydrolysis time exhibited a different degree of influence on the
cellulose characteristic wave numbers, and changes of characteristic
bands were corresponding to the acting sites of
Viscozyme® L on cellulose. Similar results were
observed for hemicellulose, CDTA-soluble pectin, and
Na2CO3-soluble pectin (Figs.3-5).