Table 2.
Phenolic acids released from sugar cane after 72 h hydrolysis
| Fraction | Enzyme mix | RC | H58 | ||
|---|---|---|---|---|---|
| pCA | FA | pCA | FA | ||
| % of pCA ester | % of FA ester | % of pCA ester | % of FA ester | ||
| Pith | Background (substrate only) | 0.1 | <0.1 | <0.1 | <0.1 |
| C-X | 1.5 ± 0.0 | 1.0 ± 0.3 | 1.0 ± 0.3 | 1.5 ± 1.1 | |
| C-X-AnFaeA | 1.4 ± 0.3 | 18.3 ± 0.8 | 1.0 ± 0.0 | 46.8 ± 11.9 | |
| C-X-TsFaeC | 6.7 ± 0.4 | 20.9 ± 0.7 | 5.5 ± 0.5 | 48.6 ± 9.9 | |
| C-X-NcFaeD | 1.5 ± 0.1 | 2.2 ± 0.5 | 1.1 ± 0.2 | 7.0 ± 4.8 | |
| Interface | Background (substrate only) | 0.3 | <0.1 | 0.3 | <0.1 |
| C-X | 1.9 ± 0.2 | 0.1 ± 0.2 | 1.6 ± 0.3 | 1.7 ± 0.7 | |
| C-X-AnFaeA | 1.6 ± 0.1 | 9.7 ± 0.4 | 1.8 ± 0.2 | 34.3 ± 4.2 | |
| C-X-TsFaeC | 8.8 ± 0.1 | 13.4 ± 0.1 | 8.7 ± 0.4 | 34.0 ± 3.6 | |
| C-X-NcFaeD | 2.0 ± 0.1 | 1.9 ± 0.2 | 1.7 ± 0.1 | 4.1 ± 0.5 |
The release of phenolic acids (ferulic acid, FA, and p-coumaric acid, pCA) is expressed as percentage of phenolic acids in ester form, as the hydrolysis conditions are too mild to cleave ether linkages. The values significantly different from the amount released by the C-X mixture are marked in bold (t-test; P < 0.01).