Table 12.
Overview on the extraction experiments by Feng Liu et al. to investigate the influence of the extraction technique, solvent, extraction time, and temperature on the extraction yield of PAs in Symphytum. Results correspond to lycopsamine determined by HPLC- ESI-MS [116].
| Technique | Sample (g) | Volume (mL) | Time (min) | Temperature (°C) | Solvent | Result (ppm) | |
|---|---|---|---|---|---|---|---|
| 1 | Sonication | 1 | 50 | 10 | Room Temperature | Methanol/Water (50/50) | approx. 7.5 |
| 2 | Sonication | 1 | 50 | 10 | Room Temperature | Methanol/Water (50/50), pH: 2.5 | approx. 7.5 |
| 3 | Sonication | 1 | 50 | 10 | Room Temperature | Methanol/Chloroform (15/85) | approx. 1.5 |
| 4 | Sonication | 1 | 50 | 10 | Room Temperature | Methanol | approx. 3.0 |
| 5 | Sonication | 1 | 50 | 10 | Room Temperature | Ethanol 95% | approx. 1.0 |
| 6 | Reflux | 1 | 60 | 60 | 65 | Methanol/Water (50/50) | approx. 30 |
| 7 | PHWE | 1 | 60 | 40 | 60 | Methanol/Water (50/50) | approx. 12.5 |
| 8 | PHWE | 1 | 60 | 40 | 80 | Methanol/Water (50/50) | approx. 10.0 |