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Treatment variables for optimization of triterpenoid extraction from Swertia chirata using central composite design
| Variables | Levels of variables | ||||||
|---|---|---|---|---|---|---|---|
| Codes | − 1.68 | − 1 | 0 | + 1 | + 1.68 | ||
| Temperature (°C) | X 1 | 20 | 35 | 50 | 65 | 80 | |
| Solvent composition | X 3 | 15 | 30 | 45 | 60 | 75 | |
| Particle size (mm) | X 5 | 0.5 | 2.0 | 3.5 | 4.0 | 5.5 | |
