From: Advanced biorefinery in lower termite-effect of combined pretreatment during the chewing process
 | Wavenumbers (cm-1) | Assignments |
---|---|---|
Lignin | Â | |
1 | 1714 to 1725 | Stretching of C = O unconjugated to aromatic rings (oxidized side-chains) |
3 | 1655 | Stretching of C = O conjugated to aromatic rings |
4 | 1594 to 1609 | Aromatic ring vibrations and C = O stretching |
6 | 1504 to 1515 | Aromatic ring vibrations |
7 | 1462 to 1464 | Asymmetric C-H bending (in CH3 and -CH2-) |
8 | 1421 to 1424 | Aromatic ring vibrations |
10 | 1365 | Symmetric deformation of C-H in methyl groups |
11 | 1360 | Phenolic hydroxyl vibrations |
12 | 1270 (shoulder) | Vibrations of guaiacyl rings and stretching vibrations of C-O bonds |
13 | 1216 to 1225 | C-C, C-O and C = O stretching (G condensed > G etherified) |
14 | 1160 | Deformation vibrations of C-H bonds on benzene rings |
16 | 1090 to 1075 | Deformation vibrations of C-O bonds in secondary alcohols and aliphatic ethers |
17 | 1030 to 1033 | Deformation vibrations of C-H bonds in aromatic rings |
Polysaccharide | Â | |
9 | 1370 | Symmetric bending of aliphatic C-H |
15 | 1030 to 1170 | C-O stretching in alcohols |
18 | 890 | β-Glycosidic linkages in pyranose units |
Protein | Â | |
2 | 1655 to 1658 | C = O stretching in amides (I) |
5 | 1516 | C = O stretching in amides (II) |