Table 3.
Factorial 23 design for the production of enzymes (IU/g) in 72 h of SSF with A. niger F12 and 1:1 (w/w) coffee waste:wheat bran under different conditions of temperature, pH and initial moisture content.
| Run | X1 a | X2 b | X3 c | β-Mannanase (IU/g) * | β-Glucosidase (IU/g) * |
|---|---|---|---|---|---|
| 1 | −1 (29) | −1 (5) | −1 (5.6) | 37.31 ± 0.46 | 35.58 ± 2.06 |
| 2 | +1 (35) | −1 (5) | −1 (5.6) | 39.26 ± 3.71 | 32.92 ± 0.91 |
| 3 | −1 (29) | +1 (7) | −1 (5.6) | 35.96 ± 0.47 | 40.01 ± 0.61 |
| 4 | +1 (35) | +1 (7) | −1 (5.6) | 44.71 ± 2.19 | 33.65 ± 2.12 |
| 5 | −1 (29) | −1 (5) | +1 (10.4) | 35.14 ± 1.03 | 29.87 ± 2.01 |
| 6 | +1 (35) | −1 (5) | +1 (10.4) | 42.62 ± 2.03 | 34.62 ± 0.98 |
| 7 | −1 (29) | +1 (7) | +1 (10.4) | 37.91 ± 2.00 | 36.29 ± 1.72 |
| 8 | +1 (35) | +1 (7) | +1 (10.4) | 49.65 ± 0.83 | 36.09 ± 1.67 |
| 9 | 0 (32) | 0 (6) | 0 (8) | 59.03 ± 2.30 | 43.10 ± 1.60 |
| 10 | 0 (32) | 0 (6) | 0 (8) | 62.40 ±2.30 | 43.62 ± 1.39 |
| 11 | 0 (32) | 0 (6) | 0 (8) | 63.50 ± 2.97 | 41.77 ± 1.80 |
* Mean ± standard error; a X1: temperature (°C); b X2: pH; c X3: initial moisture content (the uncoded values within parentheses are the volumes of solution added to 10 g of solid substrate).