| Absorbance | Plant Part | Species |
| 0.003 | Leaves | Acacia nilotica |
| 0.002 | Leaves | Acacia seyal |
| 0.004 | Bark | Acacia nilotica |
| 0.002 | Bark | Acacia seyal |
| 0.001 | Bark | Acacia senegal |
| 0.004 | Mature fruits | Acacia nilotica |
| 0.003 | Immature fruits | Acacia nilotica |