Table 2 Quantification of the main components (total lignin, xylose and glucose) of eucalyptus bark (HGU an EG clones) after hot water extraction and each pretreatment step
Treatment | Cell-wall components (%) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Liquor fraction | Monosaccharides | |||||||||
5-HMF (mg/g bark) | Total lignin | Xylose | Glucose | Treatment yield* | ||||||
EG | HGU | EG | HGU | EG | HGU | EG | HGU | EG | HGU | |
Hot Water | - | - | 25.1 ± 0.3 | 27.1 ± 0.6 | 15.0 ± 0.8 | 12.0 ± 0.2 | 41.5 ± 10.1 | 54.5 ± 11.7 | 100,0 | 100,0 |
Acid 1% | 0.20 ± 0.05 | 0.23 ± 0.03 | 32.0 ± 0.3 | 32.0 ± 0.4 | 3.3 ± 0.5 | 4.2 ± 1.0 | 54.8 ± 14.0 | 47.2 ± 5.4 | 92,9 | 64,0 |
Acid 1% + NaOH 0.25% | 0.03 ± 0.01 | 0.03 ± 0.01 | 30.7 ± 2.2 | 22.3 ± 0.6 | 2.4 ± 0.3 | 3.1 ± 0.4 | 58.6 ± 14.3 | 63.2 ± 1.6 | 88,2 | 63,1 |
Acid 1% + NaOH 0.5% | - | - | 28.1 ± 0.3 | 22.6 ± 1.4 | 1.9 ± 0.2 | 2.7 ± 0.5 | 64.9 ± 6.1 | 66.5 ± 10.6 | 82,9 | 63,0 |
Acid 1% + NaOH 1% | - | - | 23.9 ± 0.2 | 18.3 ± 0.3 | 1.6 ± 0.3 | 2.5 ± 0.3 | 66.5 ± 10.5 | 72.2 ± 10.7 | 78,7 | 59,2 |
Acid 1% + NaOH 2% | - | - | 17.0 ± 0.2 | 13.0 ± 0.2 | 1.5 ± 0.5 | 1.7 ± 0.4 | 68.9 ± 3.3 | 73.4 ± 3.0 | 64,3 | 52,9 |
Acid 1% + NaOH 4% | - | - | 14.7 ± 0.2 | 11.6 ± 0.1 | 1.8 ± 0.2 | 1.4 ± 0.2 | 75.8 ± 6.7 | 81.15 ± 1.5 | 66,7 | 54,2 |
NaOH 4% | - | - | 19.3 ± 0.3 | 18.4 ± 0.6 | 12.0 ± 3.3 | 13.3 ± 3.8 | 56.1 ± 17.0 | 61.8 ± 12.3 | 73,1 | 63,4 |