Table 3.
Effect of addition of naringin and chitosan on in vitro methane production.
| Item | Treatments | SEM | p-Value | Contrast | |||||
|---|---|---|---|---|---|---|---|---|---|
| CTL | NA1 | NA2 | CHI1 | CHI2 | L | Q | |||
| Gmax (mL/g DM) | 602 | 607.5 | 594.3 | 504.3 | 572.0 | 29.49 | 0.16 | 0.36 | 0.24 |
| A (h) | 2.5 | 2.7 | 2.8 | 2.8 | 2.8 | 0.11 | 0.42 | 0.21 | 0.22 |
| K(%/h) | 0.07 | 0.09 | 0.08 | 0.09 | 0.10 | 0.008 | 0.30 | 0.41 | 0.06 |
| GP24 (mL/g DM) | 417.5 | 436.6 | 413.3 | 405.0 | 431.6 | 17.90 | 0.71 | 0.68 | 0.53 |
| Methane (mL/g DM) | 40.9 b | 43.2 b | 35.9 b,c | 27.9 c | 51.8 a | 1.78 | <0.001 | 0.36 | 0.01 |
CTL, control treatment; NA1, naringin (1.5 g/kg DM); NA2, naringin (3.0 g/kg DM); CHI1, chitosan (1.5 g/kg DM); CHI2, chitosan, (3.0 g/kg DM). Gmax, maximum gas production; A, lag period before the gas production begins (lag phase); K, constant gas production rate; GP24, gas production at 24 h of fermentation time. abc Different letters in the same row are statistically different; SEM, standard error of the difference among means; surface response: L: linear contrast; Q: quadratic contrast.