Table 1.
Independent variables in the IV-optimal mixture design for magnetic-stirrer-assisted extraction* and content of total phenols (TP) and oleuropein in the extracts.
| Standard | Run | X1 (%, w/w) |
X2 (%, w/w) |
X3 (%, w/w) |
TP (mg/mL) |
Oleuropein (mg/mL) |
|---|---|---|---|---|---|---|
| 14 | 1 | 56.7 | 33.3 | 10.0 | 3.557 | 1.158 |
| 16 | 2 | 10.0 | 80.0 | 10.0 | 5.275 | 1.489 |
| 4 | 3 | 10.0 | 89.0 | 1.0 | 5.398 | 1.201 |
| 3 | 4 | 36.3 | 62.7 | 1.0 | 4.903 | 1.045 |
| 11 | 5 | 28.6 | 63.6 | 7.8 | 4.792 | 1.227 |
| 7 | 6 | 68.1 | 28.6 | 3.3 | 3.559 | 1.078 |
| 6 | 7 | 68.1 | 28.6 | 3.3 | 2.842 | 0.888 |
| 12 | 8 | 28.6 | 63.6 | 7.8 | 5.359 | 1.574 |
| 2 | 9 | 49.5 | 49.5 | 1.0 | 4.293 | 1.224 |
| 10 | 10 | 28.6 | 63.6 | 7.8 | 5.555 | 1.557 |
| 13 | 11 | 80.0 | 10.0 | 10.0 | 1.758 | 0.606 |
| 5 | 12 | 10.0 | 89.0 | 1.0 | 5.863 | 0.552 |
| 9 | 13 | 84.5 | 10.0 | 5.5 | 1.940 | 0.661 |
| 15 | 14 | 45.0 | 45.0 | 10.0 | 3.315 | 0.988 |
| 8 | 15 | 84.5 | 10.0 | 5.5 | 1.813 | 0.659 |
| 1 | 16 | 89.0 | 10.0 | 1.0 | 1.547 | 0.649 |
X1 = polypropylene glycol, X2 = water, X3 = lactic acid. * = magnetic-stirrer-assisted extraction, performed at 25 °C and 300 rpm.