FT-IR spectra of cell wall polysaccharides
The characteristic spectra of pectin, hemicellulose, and cellulose
exhibit a strong absorption band in the 1800-800 cm-1region (Yapo & Koffi, 2008). To reveal the effect of enzyme hydrolysis
parameters on the main components in the cell wall of peanut, the
characteristic wave numbers of cell wall polysaccharides under different
extraction conditions were measured within two specific regions,
1800-1200 cm-1 and 1200-800 cm-1.
FT-IR spectra are shown in Figs. 2-5, and the main characteristic wave
numbers measured in the present study and infrared spectral wave numbers
of
cell
wall polysaccharides in available literature are listed in
Table
2.
Cellulose is a linear homopolymer composed of 1,4-linkedβ -D-Glcp units (1,4-linked β -D-glucan), while
hemicellulose is a polymer composed of different types of
monosaccharides such as pentose and hexose (e.g. xylose, arabinose, and
galactose). Cellulose and hemicellulose are combined by hydrogen bond
forming the network structure of cell wall which is filled with pectin
(Frankova & Fry, 2013). In the case of plant cell wall, polysaccharides
are bonded with each other, which may cause the slight shift of
characteristic bands (Szymanska-Chargot & Zdunek, 2013). Slight
differences were observed in the characteristic wave numbers of cell
wall polysaccharides measured herein and those reported in previous
studies (Kačuráková, Smith, & Gidley, 2002; Fellah, Anjukandi, &
Waterland, 2009; Chatjigakis, 1998; Mccann, Defernez, & Urbanowicz,
2007; Synytsya, J Čopı́ková, & P Matějka, 2003) (Table 2).