Table 1. Proximate components, minerals, and bioactive substances in the fermented tea dregs.
| Items1 | Control | T.koningii | A.niger | P-value |
|---|---|---|---|---|
| Proximate components (g/kg) | ||||
| DM | 391 ± 3.5a | 344 ± 6.3b | 297 ± 6.87c | <0.001 |
| Crude protein | 230 ± 4.24c | 265 ± 3.3b | 307 ± 3.3a | <0.001 |
| Ether extract | 29 ± 4.0 | 33 ± 4.4 | 33 ± 4.0 | 0.242 |
| Crude fiber | 182 ± 3.4c | 223 ± 3.8a | 197 ± 12.2b | <0.001 |
| NDF | 439 ± 5.8c | 493 ± 10.9a | 463 ± 5.5b | <0.001 |
| ADF | 242 ± 6.5c | 295 ± 5.1a | 268 ± 22.6b | <0.001 |
| Ash | 32 ± 0.4c | 38 ± 0.5b | 41 ± 0.5a | <0.001 |
| Carbohydrates | 709 ± 2.4a | 666 ± 6.8b | 618 ± 4.1c | <0.001 |
| Minerals (mg/kg DM) | ||||
| Calcium | 5333 ± 68.4b | 6378 ± 121.9a | 6834 ± 90.2a | <0.001 |
| Phosphate | 6056 ± 68.4b | 6699 ± 85.4a | 6927 ± 88.0a | <0.001 |
| Potassium | 3969 ± 77.46c | 4940 ± 54.6b | 5332 ± 87.1a | <0.001 |
| Magnesium | 1610 ± 23.0c | 2048 ± 80.6b | 2192 ± 31.9a | <0.001 |
| Manganese | 970 ± 7.55c | 1193 ± 16.0b | 1311 ± 47.41a | <0.001 |
| Iron | 431 ± 14.8c | 467 ± 7.9b | 565 ± 12.6a | <0.001 |
| Zinc | 26 ± 1.2c | 32 ± 0.8b | 34 ± 1.2a | <0.001 |
| Copper | 10 ± 0.8b | 14 ± 0.8a | 15 ± 0.8a | <0.001 |
| Sodium | ND | ND | ND | − |
| Bioactive substances | ||||
| Reducing sugars (g/kg DM) | 7.40 ± 0.33c | 17.96 ± 0.46a | 14.43 ± 0.58b | <0.001 |
| Total polyphenols (gGAE/100 g DM) | 10.14 ± 0.33b | 9.89 ± 0.36b | 13.15 ± 0.67a | <0.001 |
| Total flavonoids (gRE/100 g DM) | 6.33 ± 0.22b | 5.82 ± 0.40b | 12.85 ± 0.49a | <0.001 |
| Theasaponins (mg/100 g DM) | 264.33 ± 16.40b | 221.26 ± 3.35c | 291.63 ± 17.52a | <0.001 |
| Caffeine (mg/100 g DM) | 124.16 ± 2.51b | 146.22 ± 4.39a | ND | <0.001 |
Means with different letters in the same row (a–c) indicated a significant difference according to Duncan’s multiple comparison tests at P< 0.05.
1DM, dry mass; NDF, neutral detergent fiber; ADF, acid detergent fiber; ND, value under detection limits; GAE, gallic acid equivalent; RE, rutin equivalent.