The band in the range of 1500e1700 cm1 represents the
aromatic ring stretch (which is mostly due to lignin as the
biomass contains negligible amount of protein) [48]. C]C of
aromatic skeletal vibrations in lignin appears in the region of
1500e1700 cm1 and CeH symmetric and asymmetric
stretching bands in the region of 2900 cm1. Several workers
proposed different peak pairs for representation of crystalinity hydrolysis [49]. The peak ratio (amorphous/crystalline) was
found as follows: bonbogori (1.79), moj (1.23) and areca nut
husk (1.02) (Fig. 6). Presence of amorphous cellulose content in
lignocellulosic fiber signifies the easier enzymatic hydrolysis,
as described in previous section. This result showed that
bonbogori was more amenable for enzymatic hydrolysis than
moj and areca nut husk. These results antagonize with the
results obtained by X-ray diffraction analysis of lignocellulosic
materials as described in previous section.