Table 4 Level and range of independent variables chosen for L-DOPA production
Factor | Variable | Unit | Range and level of coded values | ||
|---|---|---|---|---|---|
−1 | 0 | +1 | |||
A | L-Tyrosine | g l-1 | 0.5 | 0.75 | 1.0 |
B | pH | Unit | 3 | 4.5 | 6 |
C | Ascorbic acid | mg l-1 | 10 | 30 | 50 |
D | Copper sulphate | mg l-1 | 10 | 20 | 30 |