Table 3.
Ethanol production from grasses by SSCF process.
| Grasses | Ethanol | % of the theoretical values | |
|---|---|---|---|
| g/L | g/g substrate | ||
| Sri Lanka | 1.14 ± 0.09a | 0.14 ± 0.01a | 32.72 ± 2.69a |
| Ratchaburi | 1.10 ± 0.10a | 0.14 ± 0.01a | 30.95 ± 2.81a,b |
| α-cellulose + xylan | 1.06 ± 0.30a,b | 0.13 ± 0.04a,b | 23.01 ± 6.47b |
| Dwarf napier | 0.98 ± 0.16a,b | 0.12 ± 0.02a,b | 30.60 ± 4.90a,b |
| Napier | 0.97 ± 0.31a,b | 0.12 ± 0.04a,b | 30.30 ± 9.78a,b |
| Bana | 0.87 ± 0.14a,b | 0.11 ± 0.02a,b | 27.28 ± 4.56a,b |
| Prachuap Khiri Khan | 0.80 ± 0.12b | 0.10 ± 0.01b | 23.31 ± 3.48b |
| King napier | 0.40 ± 0.13c | 0.05 ± 0.02c | 13.93 ± 4.53c |
| Atratum | 0.36 ± 0.05c | 0.05 ± 0.01c | 11.64 ± 1.60c |
| Ruzi | 0.30 ± 0.06c | 0.04 ± 0.01c | 9.56 ± 1.79c |
| Pangola | 0.21 ± 0.05c | 0.03 ± 0.01c | 6.80 ± 1.58c |
| Purple guinea | 0.18 ± 0.07c | 0.02 ± 0.01c | 6.08 ± 2.49c |
Grasses (1.2 g) were pretreated with alkaline peroxide (7.5% (v/v) H2O2; pH 11.5; 35°C, 24 h). SSCF process was performed using cellulase and xylanase (72 and 1440 U, resp.) from T. reesei for hydrolysis and S. cerevisiae and P. stipitis for cofermentation at 35°C for 7 days. Positive control was 0.6 g of α-cellulose mixed with 0.6 g of xylan. Values not sharing a common superscript (a, b, c, and d) differ significantly (Duncan's Multiple Range Test).