Table 1.
Experimental independent variables at two levels used for the production of cholesterol oxidase by Streptomyces cavourensis strain NEAE-42 using Plackett–Burman design
| Code | Variables | Levels | |
|---|---|---|---|
| −1 | +1 | ||
| A | Temperature (°C) | 30 | 37 |
| B | Incubation time (days) | 5 | 7 |
| C | Inoculum size (%, v/v) | 2 | 4 |
| D | Agitation speed (rpm) | 150 | 200 |
| E | pH | 7 | 8.5 |
| F | Glucose (g/L) | 10 | 15 |
| G | Starch (g/L) | 7 | 10 |
| H | Cholesterol (g/L) | 1 | 2 |
| J | Yeast extract (g/L) | 4 | 6 |
| K | Peptone (g/L) | 3 | 5 |
| L | Ammonium sulphate (g/L) | 6 | 8 |
| M | K2HPO4 (g/L) | 0.5 | 1 |
| N | NaCl (g/L) | 0.5 | 1 |
| O | MgSO4 (g/L) | 0.2 | 0.5 |
| P | FeSO4 (g/L) | 0.0 | 0.02 |