Table 1. Five-level, three-independent variable central composite rotatable design and experimental data for response variables for optimization of C. cyrtophyllum leaf extracts.
| Run | Process variables – real and (coded) values | Responsesa | |||||
| X1, EtOH (%) | X2, Time (min) | X3, T (°C) | TPC (mg GAE/g DW) | TFC (mg RE/ | DPPH radical- scavenging capacity (%) | ABTS radical- scavenging capacity (%) | |
| 1 | 20 (−1) | 60 (−1) | 50 (−1) | 6.6±0.1 | 14.3±0.2 | 54.0±1.0 | 55.9±1.8 |
| 2 | 20 (−1) | 60 (−1) | 70 (1) | 11.0±0.1 | 20.3±0.4 | 72.9±1.2 | 87.6±2.7 |
| 3 | 20 (−1) | 100 (1) | 50 (−1) | 7.8±0.1 | 21.8±0.8 | 61.0±0.9 | 73.2±3.0 |
| 4 | 20 (−1) | 100 (1) | 70 (1) | 12.2±0.3 | 25.2±0.7 | 76.4±1.3 | 88.0±1.5 |
| 5 | 60 (1) | 60 (−1) | 50 (−1) | 13.6±0.3 | 41.5±0.4 | 76.5±0.7 | 89.2±0.7 |
| 6 | 60 (1) | 60 (−1) | 70 (1) | 15.0±0.6 | 44.0±0.3 | 78.7±0.2 | 90.0±2.0 |
| 7 | 60 (1) | 100 (1) | 50 (−1) | 14.8±0.5 | 42.5±0.8 | 79.9±0.4 | 91.1±1.3 |
| 8 | 60 (1) | 100 (1) | 70 (1) | 16.2±0.2 | 48.1±1.5 | 81.7±0.5 | 87.9±0.5 |
| 9 | 74 (1.68) | 80 (0) | 60 (0) | 15.9±0.5 | 46.1±0.2 | 77.2±0.5 | 89.6±0.7 |
| 10 | 6 (−1.68) | 80 (0) | 60 (0) | 7.3±0.3 | 12.7±0.6 | 55.9±1.2 | 66.1±0.6 |
| 11 | 40 (0) | 114 (1.68) | 60 (0) | 12.7±0.6 | 36.2±0.6 | 76.6±0.6 | 89.0±0.2 |
| 12 | 40 (0) | 46 (−1.68) | 60 (0) | 11.2±0.2 | 30.0±0.5 | 71.2±0.9 | 80.7±1.1 |
| 13 | 40 (0) | 80 (0) | 77 (1.68) | 14.6±0.5 | 35.0±0.6 | 79.5±0.5 | 90.9±1.6 |
| 14 | 40 (0) | 80 (0) | 43 (−1.68) | 11.0±0.1 | 27.8±0.4 | 63.1±1.7 | 80.6±1.3 |
| 15 | 40 (0) | 80 (0) | 60 (0) | 14.8±0.8 | 42.8±0.3 | 82.8±0.3 | 89.4±0.8 |
| 16 | 40 (0) | 80 (0) | 60 (0) | 15.3±0.3 | 40.7±0.6 | 83.8±1.1 | 91.0±0.7 |
| 17 | 40 (0) | 80 (0) | 60 (0) | 15.0±0.6 | 41.4±0.5 | 83.5±1.1 | 90.1±1.0 |
| 18 | 40 (0) | 80 (0) | 60 (0) | 15.0±0.8 | 40.8±0.3 | 85.6±0.7 | 91.8±0.5 |
a
Responses are the means ± SD (n = 3).